4gw6 - Revision history

OCA at 11:34, 1 March 2024

OCA — Fri, 01 Mar 2024 11:34:35 GMT

←Older revision		Revision as of 11:34, 1 March 2024
Line 4:		Line 4:
	== Structural highlights ==		== Structural highlights ==
	<table><tr><td colspan='2'>[[4gw6]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Human_immunodeficiency_virus_type_1_(NEW_YORK-5_ISOLATE) Human immunodeficiency virus type 1 (NEW YORK-5 ISOLATE)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4GW6 FirstGlance]. <br>		<table><tr><td colspan='2'>[[4gw6]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Human_immunodeficiency_virus_type_1_(NEW_YORK-5_ISOLATE) Human immunodeficiency virus type 1 (NEW YORK-5 ISOLATE)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4GW6 FirstGlance]. <br>
-	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ARS:ARSENIC'>ARS</scene>, <scene name='pdbligand=LF2:(2S)-[6-BROMO-4-(4-CHLOROPHENYL)-2-METHYLQUINOLIN-3-YL](TERT-BUTOXY)ETHANOIC+ACID'>LF2</scene></td></tr>	+	</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models\|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution\|Resolution]] 2.65Å</td></tr>
		+	<tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ARS:ARSENIC'>ARS</scene>, <scene name='pdbligand=LF2:(2S)-[6-BROMO-4-(4-CHLOROPHENYL)-2-METHYLQUINOLIN-3-YL](TERT-BUTOXY)ETHANOIC+ACID'>LF2</scene></td></tr>
	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [https://pdbe.org/4gw6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [https://www.ebi.ac.uk/pdbsum/4gw6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4gw6 ProSAT]</span></td></tr>		<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [https://pdbe.org/4gw6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [https://www.ebi.ac.uk/pdbsum/4gw6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4gw6 ProSAT]</span></td></tr>
	</table>		</table>
	== Function ==		== Function ==
	[https://www.uniprot.org/uniprot/POL_HV1N5 POL_HV1N5] Gag-Pol polyprotein and Gag polyprotein may regulate their own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, Gag-Pol and Gag would promote translation, whereas at high concentration, the polyproteins encapsidate genomic RNA and then shutt off translation (By similarity). Matrix protein p17 has two main functions: in infected cell, it targets Gag and Gag-pol polyproteins to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. The second function is to play a role in nuclear localization of the viral genome at the very start of cell infection. Matrix protein is the part of the pre-integration complex. It binds in the cytoplasm the human BAF protein which prevent autointegration of the viral genome, and might be included in virions at the ration of zero to 3 BAF dimer per virion. The myristoylation signal and the NLS thus exert conflicting influences its subcellular localization. The key regulation of these motifs might be phosphorylation of a portion of MA molecules on the C-terminal tyrosine at the time of virus maturation, by virion-associated cellular tyrosine kinase. Implicated in the release from host cell mediated by Vpu (By similarity). Capsid protein p24 forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry. Interaction with human PPIA/CYPA protects the virus from restriction by human TRIM5-alpha and from an unknown antiviral activity in human cells. This capsid restriction by TRIM5 is one of the factors which restricts HIV-1 to the human species (By similarity). Nucleocapsid protein p7 encapsulates and protects viral dimeric unspliced (genomic) RNA. Binds these RNAs through its zinc fingers. Facilitates rearangement of nucleic acid secondary structure during retrotranscription of genomic RNA. This capability is referred to as nucleic acid chaperone activity (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles (By similarity). Reverse transcriptase/ribonuclease H (RT) is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5' endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA(3)-Lys binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange, known as minus-strand DNA strong stop transfer, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for two polypurine tracts (PPTs) situated at the 5'-end and near the center of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPTs that have not been removed by RNase H as primers. PPTs and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends (By similarity). Integrase catalyzes viral DNA integration into the host chromosome, by performing a series of DNA cutting and joining reactions. This enzyme activity takes place after virion entry into a cell and reverse transcription of the RNA genome in dsDNA. The first step in the integration process is 3' processing. This step requires a complex comprising the viral genome, matrix protein, Vpr and integrase. This complex is called the pre-integration complex (PIC). The integrase protein removes 2 nucleotides from each 3' end of the viral DNA, leaving recessed CA OH's at the 3' ends. In the second step, the PIC enters cell nucleus. This process is mediated through integrase and Vpr proteins, and allows the virus to infect a non dividing cell. This ability to enter the nucleus is specific of lentiviruses, other retroviruses cannot and rely on cell division to access cell chromosomes. In the third step, termed strand transfer, the integrase protein joins the previously processed 3' ends to the 5' ends of strands of target cellular DNA at the site of integration. The 5'-ends are produced by integrase-catalyzed staggered cuts, 5 bp apart. A Y-shaped, gapped, recombination intermediate results, with the 5'-ends of the viral DNA strands and the 3' ends of target DNA strands remaining unjoined, flanking a gap of 5 bp. The last step is viral DNA integration into host chromosome. This involves host DNA repair synthesis in which the 5 bp gaps between the unjoined strands are filled in and then ligated. Since this process occurs at both cuts flanking the HIV genome, a 5 bp duplication of host DNA is produced at the ends of HIV-1 integration. Alternatively, Integrase may catalyze the excision of viral DNA just after strand transfer, this is termed disintegration (By similarity).		[https://www.uniprot.org/uniprot/POL_HV1N5 POL_HV1N5] Gag-Pol polyprotein and Gag polyprotein may regulate their own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, Gag-Pol and Gag would promote translation, whereas at high concentration, the polyproteins encapsidate genomic RNA and then shutt off translation (By similarity). Matrix protein p17 has two main functions: in infected cell, it targets Gag and Gag-pol polyproteins to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. The second function is to play a role in nuclear localization of the viral genome at the very start of cell infection. Matrix protein is the part of the pre-integration complex. It binds in the cytoplasm the human BAF protein which prevent autointegration of the viral genome, and might be included in virions at the ration of zero to 3 BAF dimer per virion. The myristoylation signal and the NLS thus exert conflicting influences its subcellular localization. The key regulation of these motifs might be phosphorylation of a portion of MA molecules on the C-terminal tyrosine at the time of virus maturation, by virion-associated cellular tyrosine kinase. Implicated in the release from host cell mediated by Vpu (By similarity). Capsid protein p24 forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry. Interaction with human PPIA/CYPA protects the virus from restriction by human TRIM5-alpha and from an unknown antiviral activity in human cells. This capsid restriction by TRIM5 is one of the factors which restricts HIV-1 to the human species (By similarity). Nucleocapsid protein p7 encapsulates and protects viral dimeric unspliced (genomic) RNA. Binds these RNAs through its zinc fingers. Facilitates rearangement of nucleic acid secondary structure during retrotranscription of genomic RNA. This capability is referred to as nucleic acid chaperone activity (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles (By similarity). Reverse transcriptase/ribonuclease H (RT) is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5' endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA(3)-Lys binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange, known as minus-strand DNA strong stop transfer, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for two polypurine tracts (PPTs) situated at the 5'-end and near the center of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPTs that have not been removed by RNase H as primers. PPTs and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends (By similarity). Integrase catalyzes viral DNA integration into the host chromosome, by performing a series of DNA cutting and joining reactions. This enzyme activity takes place after virion entry into a cell and reverse transcription of the RNA genome in dsDNA. The first step in the integration process is 3' processing. This step requires a complex comprising the viral genome, matrix protein, Vpr and integrase. This complex is called the pre-integration complex (PIC). The integrase protein removes 2 nucleotides from each 3' end of the viral DNA, leaving recessed CA OH's at the 3' ends. In the second step, the PIC enters cell nucleus. This process is mediated through integrase and Vpr proteins, and allows the virus to infect a non dividing cell. This ability to enter the nucleus is specific of lentiviruses, other retroviruses cannot and rely on cell division to access cell chromosomes. In the third step, termed strand transfer, the integrase protein joins the previously processed 3' ends to the 5' ends of strands of target cellular DNA at the site of integration. The 5'-ends are produced by integrase-catalyzed staggered cuts, 5 bp apart. A Y-shaped, gapped, recombination intermediate results, with the 5'-ends of the viral DNA strands and the 3' ends of target DNA strands remaining unjoined, flanking a gap of 5 bp. The last step is viral DNA integration into host chromosome. This involves host DNA repair synthesis in which the 5 bp gaps between the unjoined strands are filled in and then ligated. Since this process occurs at both cuts flanking the HIV genome, a 5 bp duplication of host DNA is produced at the ends of HIV-1 integration. Alternatively, Integrase may catalyze the excision of viral DNA just after strand transfer, this is termed disintegration (By similarity).
-	<div style="background-color:#fffaf0;">
-	== Publication Abstract from PubMed ==
-	Allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are a very promising new class of anti-HIV-1 agents that exhibit a multimodal mechanism of action by allosterically modulating IN multimerization and interfering with IN-LEDGF/p75 binding. Selection of viral strains under ALLINI pressure has revealed an A128T substitution in HIV-1 IN as a primary mechanism of resistance. Here, we have elucidated the structural and mechanistic basis for this resistance. The A128T substitution did not affect the hydrogen bonding between ALLINI and IN that mimics the IN-LEDGF/p75 interaction, but instead altered the positioning of the inhibitor at the IN dimer interface. Consequently, the A128T substitution had only a minor effect on the ALLINI IC50 values for IN-LEDGF/p75 binding. Instead ALLINIs markedly altered the multimerization of IN by promoting aberrant, higher order wild type, but not A128T, IN oligomers. Accordingly, wild type IN catalytic activities and HIV-1 replication were potently inhibited by ALLINIs, whereas the A128T substitution in IN resulted in significant resistance to the inhibitors in both in vitro and in cell culture assays. The differential multimerization of WT and A128T INs induced by ALLINIs correlated with the differences in infectivity of HIV-1 progeny virions. Taken together, we conclude that ALLINIs primarily target IN multimerization rather than IN-LEDGF/p75 binding. Our findings provide the structural foundations for developing improved ALLINIs with increased potency and decreased potential to select for drug resistance.
-
-	The A128T resistance mutation reveals aberrant protein multimerization as the primary mechanism of action of allosteric HIV-1 integrase inhibitors.,Feng L, Sharma A, Slaughter A, Jena N, Koh Y, Shkriabai N, Larue RC, Patel PA, Mitsuya H, Kessl JJ, Engelman A, Fuchs JR, Kvaratskhelia M J Biol Chem. 2013 Apr 24. PMID:23615903<ref>PMID:23615903</ref>
-
-	From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
-	</div>
-	<div class="pdbe-citations 4gw6" style="background-color:#fffaf0;"></div>
-	== References ==
-	<references/>
	__TOC__		__TOC__
	</StructureSection>		</StructureSection>

OCA at 07:22, 26 October 2022

OCA — Wed, 26 Oct 2022 07:22:32 GMT

←Older revision		Revision as of 07:22, 26 October 2022
Line 1:		Line 1:

	==HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor==		==HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor==
-	<StructureSection load='4gw6' size='340' side='right' caption='[[4gw6]], [[Resolution\|resolution]] 2.65Å' scene=''>	+	<StructureSection load='4gw6' size='340' side='right'caption='[[4gw6]], [[Resolution\|resolution]] 2.65Å' scene=''>
	== Structural highlights ==		== Structural highlights ==
-	<table><tr><td colspan='2'>[[4gw6]] is a 1 chain structure with sequence from [~~http~~://en.wikipedia.org/wiki/~~Hiv~~-1 ~~Hiv~~-1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA]. For a <b>guided tour on the structure components</b> use [~~http~~://~~oca~~.~~weizmann.ac.il/oca-docs~~/fgij/fg.htm?mol=4GW6 FirstGlance]. <br>	+	<table><tr><td colspan='2'>[[4gw6]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Human_immunodeficiency_virus_type_1_(NEW_YORK-5_ISOLATE) Human immunodeficiency virus type 1 (NEW YORK-5 ISOLATE)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4GW6 FirstGlance]. <br>
-	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ARS:ARSENIC'>ARS</scene>, <scene name='pdbligand=LF2:(2S)-[6-BROMO-4-(4-CHLOROPHENYL)-2-METHYLQUINOLIN-3-YL](TERT-BUTOXY)ETHANOIC+ACID'>LF2</scene>~~</td></tr>~~	+	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ARS:ARSENIC'>ARS</scene>, <scene name='pdbligand=LF2:(2S)-[6-BROMO-4-(4-CHLOROPHENYL)-2-METHYLQUINOLIN-3-YL](TERT-BUTOXY)ETHANOIC+ACID'>LF2</scene></td></tr>
-	~~<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[1itg\|1itg]], [[4gvm\|4gvm]]</td></tr>~~	+	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [https://pdbe.org/4gw6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [https://www.ebi.ac.uk/pdbsum/4gw6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4gw6 ProSAT]</span></td></tr>
-	~~<tr id='gene'><td class="sblockLbl"><b>[[Gene\|Gene:]]</b></td><td class="sblockDat">gag-pol ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=11698 HIV-1])~~</td></tr>	+
-	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[~~http~~://~~oca~~.~~weizmann.ac.il/oca-docs~~/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [~~http~~://pdbe.org/4gw6 PDBe], [~~http~~://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [~~http~~://www.ebi.ac.uk/pdbsum/4gw6 PDBsum], [~~http~~://prosat.h-its.org/prosat/prosatexe?pdbcode=4gw6 ProSAT]</span></td></tr>	+
	</table>		</table>
	== Function ==		== Function ==
-	[~~[http~~://www.uniprot.org/uniprot/POL_HV1N5 POL_HV1N5]] Gag-Pol polyprotein and Gag polyprotein may regulate their own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, Gag-Pol and Gag would promote translation, whereas at high concentration, the polyproteins encapsidate genomic RNA and then shutt off translation (By similarity). Matrix protein p17 has two main functions: in infected cell, it targets Gag and Gag-pol polyproteins to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. The second function is to play a role in nuclear localization of the viral genome at the very start of cell infection. Matrix protein is the part of the pre-integration complex. It binds in the cytoplasm the human BAF protein which prevent autointegration of the viral genome, and might be included in virions at the ration of zero to 3 BAF dimer per virion. The myristoylation signal and the NLS thus exert conflicting influences its subcellular localization. The key regulation of these motifs might be phosphorylation of a portion of MA molecules on the C-terminal tyrosine at the time of virus maturation, by virion-associated cellular tyrosine kinase. Implicated in the release from host cell mediated by Vpu (By similarity). Capsid protein p24 forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry. Interaction with human PPIA/CYPA protects the virus from restriction by human TRIM5-alpha and from an unknown antiviral activity in human cells. This capsid restriction by TRIM5 is one of the factors which restricts HIV-1 to the human species (By similarity). Nucleocapsid protein p7 encapsulates and protects viral dimeric unspliced (genomic) RNA. Binds these RNAs through its zinc fingers. Facilitates rearangement of nucleic acid secondary structure during retrotranscription of genomic RNA. This capability is referred to as nucleic acid chaperone activity (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles (By similarity). Reverse transcriptase/ribonuclease H (RT) is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5' endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA(3)-Lys binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange, known as minus-strand DNA strong stop transfer, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for two polypurine tracts (PPTs) situated at the 5'-end and near the center of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPTs that have not been removed by RNase H as primers. PPTs and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends (By similarity). Integrase catalyzes viral DNA integration into the host chromosome, by performing a series of DNA cutting and joining reactions. This enzyme activity takes place after virion entry into a cell and reverse transcription of the RNA genome in dsDNA. The first step in the integration process is 3' processing. This step requires a complex comprising the viral genome, matrix protein, Vpr and integrase. This complex is called the pre-integration complex (PIC). The integrase protein removes 2 nucleotides from each 3' end of the viral DNA, leaving recessed CA OH's at the 3' ends. In the second step, the PIC enters cell nucleus. This process is mediated through integrase and Vpr proteins, and allows the virus to infect a non dividing cell. This ability to enter the nucleus is specific of lentiviruses, other retroviruses cannot and rely on cell division to access cell chromosomes. In the third step, termed strand transfer, the integrase protein joins the previously processed 3' ends to the 5' ends of strands of target cellular DNA at the site of integration. The 5'-ends are produced by integrase-catalyzed staggered cuts, 5 bp apart. A Y-shaped, gapped, recombination intermediate results, with the 5'-ends of the viral DNA strands and the 3' ends of target DNA strands remaining unjoined, flanking a gap of 5 bp. The last step is viral DNA integration into host chromosome. This involves host DNA repair synthesis in which the 5 bp gaps between the unjoined strands are filled in and then ligated. Since this process occurs at both cuts flanking the HIV genome, a 5 bp duplication of host DNA is produced at the ends of HIV-1 integration. Alternatively, Integrase may catalyze the excision of viral DNA just after strand transfer, this is termed disintegration (By similarity).	+	[https://www.uniprot.org/uniprot/POL_HV1N5 POL_HV1N5] Gag-Pol polyprotein and Gag polyprotein may regulate their own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, Gag-Pol and Gag would promote translation, whereas at high concentration, the polyproteins encapsidate genomic RNA and then shutt off translation (By similarity). Matrix protein p17 has two main functions: in infected cell, it targets Gag and Gag-pol polyproteins to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. The second function is to play a role in nuclear localization of the viral genome at the very start of cell infection. Matrix protein is the part of the pre-integration complex. It binds in the cytoplasm the human BAF protein which prevent autointegration of the viral genome, and might be included in virions at the ration of zero to 3 BAF dimer per virion. The myristoylation signal and the NLS thus exert conflicting influences its subcellular localization. The key regulation of these motifs might be phosphorylation of a portion of MA molecules on the C-terminal tyrosine at the time of virus maturation, by virion-associated cellular tyrosine kinase. Implicated in the release from host cell mediated by Vpu (By similarity). Capsid protein p24 forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry. Interaction with human PPIA/CYPA protects the virus from restriction by human TRIM5-alpha and from an unknown antiviral activity in human cells. This capsid restriction by TRIM5 is one of the factors which restricts HIV-1 to the human species (By similarity). Nucleocapsid protein p7 encapsulates and protects viral dimeric unspliced (genomic) RNA. Binds these RNAs through its zinc fingers. Facilitates rearangement of nucleic acid secondary structure during retrotranscription of genomic RNA. This capability is referred to as nucleic acid chaperone activity (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles (By similarity). Reverse transcriptase/ribonuclease H (RT) is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5' endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA(3)-Lys binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange, known as minus-strand DNA strong stop transfer, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for two polypurine tracts (PPTs) situated at the 5'-end and near the center of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPTs that have not been removed by RNase H as primers. PPTs and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends (By similarity). Integrase catalyzes viral DNA integration into the host chromosome, by performing a series of DNA cutting and joining reactions. This enzyme activity takes place after virion entry into a cell and reverse transcription of the RNA genome in dsDNA. The first step in the integration process is 3' processing. This step requires a complex comprising the viral genome, matrix protein, Vpr and integrase. This complex is called the pre-integration complex (PIC). The integrase protein removes 2 nucleotides from each 3' end of the viral DNA, leaving recessed CA OH's at the 3' ends. In the second step, the PIC enters cell nucleus. This process is mediated through integrase and Vpr proteins, and allows the virus to infect a non dividing cell. This ability to enter the nucleus is specific of lentiviruses, other retroviruses cannot and rely on cell division to access cell chromosomes. In the third step, termed strand transfer, the integrase protein joins the previously processed 3' ends to the 5' ends of strands of target cellular DNA at the site of integration. The 5'-ends are produced by integrase-catalyzed staggered cuts, 5 bp apart. A Y-shaped, gapped, recombination intermediate results, with the 5'-ends of the viral DNA strands and the 3' ends of target DNA strands remaining unjoined, flanking a gap of 5 bp. The last step is viral DNA integration into host chromosome. This involves host DNA repair synthesis in which the 5 bp gaps between the unjoined strands are filled in and then ligated. Since this process occurs at both cuts flanking the HIV genome, a 5 bp duplication of host DNA is produced at the ends of HIV-1 integration. Alternatively, Integrase may catalyze the excision of viral DNA just after strand transfer, this is termed disintegration (By similarity).
	<div style="background-color:#fffaf0;">		<div style="background-color:#fffaf0;">
	== Publication Abstract from PubMed ==		== Publication Abstract from PubMed ==
Line 24:		Line 22:
	__TOC__		__TOC__
	</StructureSection>		</StructureSection>
-	[[Category: ~~Hiv-1~~]]	+	[[Category: Large Structures]]
-	[[Category: Feng, L]]	+	[[Category: Feng L]]
-	[[Category: Kvaratskhelia, M]]	+	[[Category: Kvaratskhelia M]]
-	~~[[Category: Allosteric inhibitor]]~~	+
-	~~[[Category: Dde motif]]~~	+
-	~~[[Category: Hydrolase-hydrolase inhibitor complex]]~~	+
-	~~[[Category: Integrase~~]]	+

OCA at 10:38, 4 August 2016

OCA — Thu, 04 Aug 2016 10:38:14 GMT

←Older revision		Revision as of 10:38, 4 August 2016
Line 1:		Line 1:
		+
	==HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor==		==HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor==
	<StructureSection load='4gw6' size='340' side='right' caption='[[4gw6]], [[Resolution\|resolution]] 2.65Å' scene=''>		<StructureSection load='4gw6' size='340' side='right' caption='[[4gw6]], [[Resolution\|resolution]] 2.65Å' scene=''>
	== Structural highlights ==		== Structural highlights ==
-	<table><tr><td colspan='2'>[[4gw6]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/~~Human_immunodeficiency_virus_type_1_(new_york~~-~~5_isolate) Human immunodeficiency virus type~~ 1 ~~(new york~~-~~5 isolate)~~]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4GW6 FirstGlance]. <br>	+	<table><tr><td colspan='2'>[[4gw6]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Hiv-1 Hiv-1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4GW6 FirstGlance]. <br>
	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ARS:ARSENIC'>ARS</scene>, <scene name='pdbligand=LF2:(2S)-[6-BROMO-4-(4-CHLOROPHENYL)-2-METHYLQUINOLIN-3-YL](TERT-BUTOXY)ETHANOIC+ACID'>LF2</scene></td></tr>		</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ARS:ARSENIC'>ARS</scene>, <scene name='pdbligand=LF2:(2S)-[6-BROMO-4-(4-CHLOROPHENYL)-2-METHYLQUINOLIN-3-YL](TERT-BUTOXY)ETHANOIC+ACID'>LF2</scene></td></tr>
	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[1itg\|1itg]], [[4gvm\|4gvm]]</td></tr>		<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[1itg\|1itg]], [[4gvm\|4gvm]]</td></tr>
-	<tr id='gene'><td class="sblockLbl"><b>[[Gene\|Gene:]]</b></td><td class="sblockDat">gag-pol ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=11698 ~~Human immunodeficiency virus type~~ 1 ~~(NEW YORK-5 ISOLATE)~~])</td></tr>	+	<tr id='gene'><td class="sblockLbl"><b>[[Gene\|Gene:]]</b></td><td class="sblockDat">gag-pol ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=11698 HIV-1])</td></tr>
-	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [http://www.ebi.ac.uk/pdbsum/4gw6 PDBsum]</span></td></tr>	+	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [http://pdbe.org/4gw6 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [http://www.ebi.ac.uk/pdbsum/4gw6 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4gw6 ProSAT]</span></td></tr>
	</table>		</table>
	== Function ==		== Function ==
Line 18:		Line 19:
	From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>		From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
	</div>		</div>
		+	<div class="pdbe-citations 4gw6" style="background-color:#fffaf0;"></div>
	== References ==		== References ==
	<references/>		<references/>
	__TOC__		__TOC__
	</StructureSection>		</StructureSection>
		+	[[Category: Hiv-1]]
	[[Category: Feng, L]]		[[Category: Feng, L]]
	[[Category: Kvaratskhelia, M]]		[[Category: Kvaratskhelia, M]]

OCA at 08:25, 25 December 2014

OCA — Thu, 25 Dec 2014 08:25:49 GMT

←Older revision		Revision as of 08:25, 25 December 2014
Line 8:		Line 8:
	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [http://www.ebi.ac.uk/pdbsum/4gw6 PDBsum]</span></td></tr>		<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [http://www.ebi.ac.uk/pdbsum/4gw6 PDBsum]</span></td></tr>
	</table>		</table>
		+	== Function ==
		+	[[http://www.uniprot.org/uniprot/POL_HV1N5 POL_HV1N5]] Gag-Pol polyprotein and Gag polyprotein may regulate their own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, Gag-Pol and Gag would promote translation, whereas at high concentration, the polyproteins encapsidate genomic RNA and then shutt off translation (By similarity). Matrix protein p17 has two main functions: in infected cell, it targets Gag and Gag-pol polyproteins to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. The second function is to play a role in nuclear localization of the viral genome at the very start of cell infection. Matrix protein is the part of the pre-integration complex. It binds in the cytoplasm the human BAF protein which prevent autointegration of the viral genome, and might be included in virions at the ration of zero to 3 BAF dimer per virion. The myristoylation signal and the NLS thus exert conflicting influences its subcellular localization. The key regulation of these motifs might be phosphorylation of a portion of MA molecules on the C-terminal tyrosine at the time of virus maturation, by virion-associated cellular tyrosine kinase. Implicated in the release from host cell mediated by Vpu (By similarity). Capsid protein p24 forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry. Interaction with human PPIA/CYPA protects the virus from restriction by human TRIM5-alpha and from an unknown antiviral activity in human cells. This capsid restriction by TRIM5 is one of the factors which restricts HIV-1 to the human species (By similarity). Nucleocapsid protein p7 encapsulates and protects viral dimeric unspliced (genomic) RNA. Binds these RNAs through its zinc fingers. Facilitates rearangement of nucleic acid secondary structure during retrotranscription of genomic RNA. This capability is referred to as nucleic acid chaperone activity (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles (By similarity). Reverse transcriptase/ribonuclease H (RT) is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5' endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA(3)-Lys binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange, known as minus-strand DNA strong stop transfer, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for two polypurine tracts (PPTs) situated at the 5'-end and near the center of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPTs that have not been removed by RNase H as primers. PPTs and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends (By similarity). Integrase catalyzes viral DNA integration into the host chromosome, by performing a series of DNA cutting and joining reactions. This enzyme activity takes place after virion entry into a cell and reverse transcription of the RNA genome in dsDNA. The first step in the integration process is 3' processing. This step requires a complex comprising the viral genome, matrix protein, Vpr and integrase. This complex is called the pre-integration complex (PIC). The integrase protein removes 2 nucleotides from each 3' end of the viral DNA, leaving recessed CA OH's at the 3' ends. In the second step, the PIC enters cell nucleus. This process is mediated through integrase and Vpr proteins, and allows the virus to infect a non dividing cell. This ability to enter the nucleus is specific of lentiviruses, other retroviruses cannot and rely on cell division to access cell chromosomes. In the third step, termed strand transfer, the integrase protein joins the previously processed 3' ends to the 5' ends of strands of target cellular DNA at the site of integration. The 5'-ends are produced by integrase-catalyzed staggered cuts, 5 bp apart. A Y-shaped, gapped, recombination intermediate results, with the 5'-ends of the viral DNA strands and the 3' ends of target DNA strands remaining unjoined, flanking a gap of 5 bp. The last step is viral DNA integration into host chromosome. This involves host DNA repair synthesis in which the 5 bp gaps between the unjoined strands are filled in and then ligated. Since this process occurs at both cuts flanking the HIV genome, a 5 bp duplication of host DNA is produced at the ends of HIV-1 integration. Alternatively, Integrase may catalyze the excision of viral DNA just after strand transfer, this is termed disintegration (By similarity).
	<div style="background-color:#fffaf0;">		<div style="background-color:#fffaf0;">
	== Publication Abstract from PubMed ==		== Publication Abstract from PubMed ==

OCA at 11:39, 21 December 2014

OCA — Sun, 21 Dec 2014 11:39:18 GMT

←Older revision		Revision as of 11:39, 21 December 2014
Line 1:		Line 1:
-	~~{{STRUCTURE_4gw6\| PDB=4gw6 \| SCENE= }}~~	+	==HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor==
-	===HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor===	+	<StructureSection load='4gw6' size='340' side='right' caption='[[4gw6]], [[Resolution\|resolution]] 2.65Å' scene=''>
-	~~{{ABSTRACT_PUBMED_23615903}}~~	+	== Structural highlights ==
		+	<table><tr><td colspan='2'>[[4gw6]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human_immunodeficiency_virus_type_1_(new_york-5_isolate) Human immunodeficiency virus type 1 (new york-5 isolate)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4GW6 FirstGlance]. <br>
		+	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ARS:ARSENIC'>ARS</scene>, <scene name='pdbligand=LF2:(2S)-[6-BROMO-4-(4-CHLOROPHENYL)-2-METHYLQUINOLIN-3-YL](TERT-BUTOXY)ETHANOIC+ACID'>LF2</scene></td></tr>
		+	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[1itg\|1itg]], [[4gvm\|4gvm]]</td></tr>
		+	<tr id='gene'><td class="sblockLbl"><b>[[Gene\|Gene:]]</b></td><td class="sblockDat">gag-pol ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=11698 Human immunodeficiency virus type 1 (NEW YORK-5 ISOLATE)])</td></tr>
		+	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4gw6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gw6 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4gw6 RCSB], [http://www.ebi.ac.uk/pdbsum/4gw6 PDBsum]</span></td></tr>
		+	</table>
		+	<div style="background-color:#fffaf0;">
		+	== Publication Abstract from PubMed ==
		+	Allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are a very promising new class of anti-HIV-1 agents that exhibit a multimodal mechanism of action by allosterically modulating IN multimerization and interfering with IN-LEDGF/p75 binding. Selection of viral strains under ALLINI pressure has revealed an A128T substitution in HIV-1 IN as a primary mechanism of resistance. Here, we have elucidated the structural and mechanistic basis for this resistance. The A128T substitution did not affect the hydrogen bonding between ALLINI and IN that mimics the IN-LEDGF/p75 interaction, but instead altered the positioning of the inhibitor at the IN dimer interface. Consequently, the A128T substitution had only a minor effect on the ALLINI IC50 values for IN-LEDGF/p75 binding. Instead ALLINIs markedly altered the multimerization of IN by promoting aberrant, higher order wild type, but not A128T, IN oligomers. Accordingly, wild type IN catalytic activities and HIV-1 replication were potently inhibited by ALLINIs, whereas the A128T substitution in IN resulted in significant resistance to the inhibitors in both in vitro and in cell culture assays. The differential multimerization of WT and A128T INs induced by ALLINIs correlated with the differences in infectivity of HIV-1 progeny virions. Taken together, we conclude that ALLINIs primarily target IN multimerization rather than IN-LEDGF/p75 binding. Our findings provide the structural foundations for developing improved ALLINIs with increased potency and decreased potential to select for drug resistance.

-	~~==Function==~~	+	The A128T resistance mutation reveals aberrant protein multimerization as the primary mechanism of action of allosteric HIV-1 integrase inhibitors.,Feng L, Sharma A, Slaughter A, Jena N, Koh Y, Shkriabai N, Larue RC, Patel PA, Mitsuya H, Kessl JJ, Engelman A, Fuchs JR, Kvaratskhelia M J Biol Chem. 2013 Apr 24. PMID:23615903<ref>PMID:23615903</ref>
-	[[http://www.uniprot.org/uniprot/POL_HV1N5 POL_HV1N5]] Gag-Pol polyprotein and Gag polyprotein may regulate their own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, Gag-Pol and Gag would promote translation, whereas at high concentration, the polyproteins encapsidate genomic RNA and then shutt off translation (By similarity). Matrix protein p17 has two main functions: in infected cell, it targets Gag and Gag-pol polyproteins to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. The ~~second function is to play a role in nuclear localization of the viral genome at the very start of cell infection. Matrix~~ protein is the ~~part~~ of ~~the pre-integration complex. It binds in the cytoplasm the human BAF protein which prevent autointegration~~ of the viral genome, and might be included in virions at the ration of zero to 3 BAF dimer per virion. The myristoylation signal and the NLS thus exert conflicting influences its subcellular localization. The key regulation of these motifs might be phosphorylation of a portion of MA molecules on the C-terminal tyrosine at the time of virus maturation, by virion-associated cellular tyrosine kinase. Implicated in the release from host cell mediated by Vpu (By similarity). Capsid protein p24 forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry. Interaction with human PPIA/CYPA protects the virus from restriction by human TRIM5-alpha and from an unknown antiviral activity in human cells. This capsid restriction by TRIM5 is one of the factors which restricts HIV-1 ~~to the human species (By similarity)~~. Nucleocapsid protein p7 encapsulates and protects viral dimeric unspliced (genomic) RNA. Binds these RNAs through its zinc fingers. Facilitates rearangement of nucleic acid secondary structure during retrotranscription of genomic RNA. This capability is referred to as nucleic acid chaperone activity (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles (By similarity). Reverse transcriptase/ribonuclease H (RT) is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5' endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA(3)-Lys binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, ~~resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange~~, ~~known as minus-strand DNA strong stop transfer~~, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for two polypurine tracts (PPTs) situated at the 5'-end and near the center of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPTs that have not been removed by RNase H as primers. PPTs and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, ~~linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends (By similarity). Integrase catalyzes viral DNA integration into the host chromosome~~, by performing a series of DNA cutting and joining reactions. This enzyme activity takes place after virion entry into a cell and reverse transcription of the RNA genome in dsDNA. The first step in the integration process is 3' processing. This step requires a complex comprising the viral genome, ~~matrix protein~~, Vpr and integrase. This complex is called the pre-integration complex (PIC). The integrase protein removes 2 nucleotides from each 3' end of the viral DNA, leaving recessed CA OH's at the 3' ends. In the second step, the PIC enters cell nucleus. This process is mediated through integrase and Vpr proteins, and allows the virus to infect a non dividing cell. This ability to enter the nucleus is specific of lentiviruses, other retroviruses cannot and rely on cell division to access cell chromosomes. In the third step, termed strand transfer, the integrase protein joins the previously processed 3' ends to the 5' ends of strands of target cellular DNA at the site of integration. The 5'-ends are produced by integrase-catalyzed staggered cuts, 5 bp apart. A ~~Y-shaped~~, ~~gapped~~, ~~recombination intermediate results, with the 5'-ends of the viral DNA strands and the 3' ends of target DNA strands remaining unjoined, flanking a gap of 5 bp~~. The last step is viral DNA integration into host chromosome. This involves host DNA repair synthesis in which the 5 bp gaps between the unjoined strands are filled in and then ligated. Since this process occurs at both cuts flanking the HIV genome, a 5 bp duplication of host DNA is produced at the ends of HIV-1 integration. Alternatively, Integrase may catalyze the excision of viral DNA just after strand transfer, this is termed disintegration (By similarity).	+

-	~~==About this Structure==~~	+	From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
-	~~[[4gw6]] is~~ a ~~1 chain structure with sequence from [http://en~~.~~wikipedia~~.~~org/wiki/Human_immunodeficiency_virus_type_1_(new_york-5_isolate) Human immunodeficiency virus type 1 (new york-5 isolate)]~~. ~~Full crystallographic information is available from [http:~~/~~/oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA].~~	+	</div>
-		+	== References ==
-	==~~Reference~~==	+	<references/>
-	~~<ref group="xtra">PMID:023615903</ref>~~<references ~~group="xtra"~~/><~~references~~/>	+	__TOC__
-	[[Category: Feng, L.]]	+	</StructureSection>
-	[[Category: Kvaratskhelia, M.]]	+	[[Category: Feng, L]]
		+	[[Category: Kvaratskhelia, M]]
	[[Category: Allosteric inhibitor]]		[[Category: Allosteric inhibitor]]
	[[Category: Dde motif]]		[[Category: Dde motif]]
	[[Category: Hydrolase-hydrolase inhibitor complex]]		[[Category: Hydrolase-hydrolase inhibitor complex]]
	[[Category: Integrase]]		[[Category: Integrase]]

OCA at 09:19, 19 June 2013

OCA — Wed, 19 Jun 2013 09:19:22 GMT

←Older revision		Revision as of 09:19, 19 June 2013
Line 8:		Line 8:
	==About this Structure==		==About this Structure==
	[[4gw6]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human_immunodeficiency_virus_type_1_(new_york-5_isolate) Human immunodeficiency virus type 1 (new york-5 isolate)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA].		[[4gw6]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human_immunodeficiency_virus_type_1_(new_york-5_isolate) Human immunodeficiency virus type 1 (new york-5 isolate)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA].
		+
		+	==Reference==
		+	<ref group="xtra">PMID:023615903</ref><references group="xtra"/><references/>
	[[Category: Feng, L.]]		[[Category: Feng, L.]]
	[[Category: Kvaratskhelia, M.]]		[[Category: Kvaratskhelia, M.]]

OCA at 06:42, 8 May 2013

OCA — Wed, 08 May 2013 06:42:58 GMT

←Older revision		Revision as of 06:42, 8 May 2013
Line 1:		Line 1:
	{{STRUCTURE_4gw6\| PDB=4gw6 \| SCENE= }}		{{STRUCTURE_4gw6\| PDB=4gw6 \| SCENE= }}
	===HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor===		===HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor===
		+	{{ABSTRACT_PUBMED_23615903}}

	==Function==		==Function==

OCA at 07:50, 2 May 2013

OCA — Thu, 02 May 2013 07:50:22 GMT

←Older revision		Revision as of 07:50, 2 May 2013
Line 1:		Line 1:
-	~~'''Unreleased structure'''~~	+	{{STRUCTURE_4gw6\| PDB=4gw6 \| SCENE= }}
		+	===HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor===

-	The entry ~~4gw6~~ is ~~ON HOLD~~ ~~until Paper Publication~~	+	==Function==
		+	[[http://www.uniprot.org/uniprot/POL_HV1N5 POL_HV1N5]] Gag-Pol polyprotein and Gag polyprotein may regulate their own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, Gag-Pol and Gag would promote translation, whereas at high concentration, the polyproteins encapsidate genomic RNA and then shutt off translation (By similarity). Matrix protein p17 has two main functions: in infected cell, it targets Gag and Gag-pol polyproteins to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. The second function is to play a role in nuclear localization of the viral genome at the very start of cell infection. Matrix protein is the part of the pre-integration complex. It binds in the cytoplasm the human BAF protein which prevent autointegration of the viral genome, and might be included in virions at the ration of zero to 3 BAF dimer per virion. The myristoylation signal and the NLS thus exert conflicting influences its subcellular localization. The key regulation of these motifs might be phosphorylation of a portion of MA molecules on the C-terminal tyrosine at the time of virus maturation, by virion-associated cellular tyrosine kinase. Implicated in the release from host cell mediated by Vpu (By similarity). Capsid protein p24 forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry. Interaction with human PPIA/CYPA protects the virus from restriction by human TRIM5-alpha and from an unknown antiviral activity in human cells. This capsid restriction by TRIM5 is one of the factors which restricts HIV-1 to the human species (By similarity). Nucleocapsid protein p7 encapsulates and protects viral dimeric unspliced (genomic) RNA. Binds these RNAs through its zinc fingers. Facilitates rearangement of nucleic acid secondary structure during retrotranscription of genomic RNA. This capability is referred to as nucleic acid chaperone activity (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles (By similarity). Reverse transcriptase/ribonuclease H (RT) is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5' endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA(3)-Lys binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange, known as minus-strand DNA strong stop transfer, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for two polypurine tracts (PPTs) situated at the 5'-end and near the center of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPTs that have not been removed by RNase H as primers. PPTs and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends (By similarity). Integrase catalyzes viral DNA integration into the host chromosome, by performing a series of DNA cutting and joining reactions. This enzyme activity takes place after virion entry into a cell and reverse transcription of the RNA genome in dsDNA. The first step in the integration process is 3' processing. This step requires a complex comprising the viral genome, matrix protein, Vpr and integrase. This complex is called the pre-integration complex (PIC). The integrase protein removes 2 nucleotides from each 3' end of the viral DNA, leaving recessed CA OH's at the 3' ends. In the second step, the PIC enters cell nucleus. This process is mediated through integrase and Vpr proteins, and allows the virus to infect a non dividing cell. This ability to enter the nucleus is specific of lentiviruses, other retroviruses cannot and rely on cell division to access cell chromosomes. In the third step, termed strand transfer, the integrase protein joins the previously processed 3' ends to the 5' ends of strands of target cellular DNA at the site of integration. The 5'-ends are produced by integrase-catalyzed staggered cuts, 5 bp apart. A Y-shaped, gapped, recombination intermediate results, with the 5'-ends of the viral DNA strands and the 3' ends of target DNA strands remaining unjoined, flanking a gap of 5 bp. The last step is viral DNA integration into host chromosome. This involves host DNA repair synthesis in which the 5 bp gaps between the unjoined strands are filled in and then ligated. Since this process occurs at both cuts flanking the HIV genome, a 5 bp duplication of host DNA is produced at the ends of HIV-1 integration. Alternatively, Integrase may catalyze the excision of viral DNA just after strand transfer, this is termed disintegration (By similarity).

-	~~Authors~~: Feng, L., Kvaratskhelia, M.	+	==About this Structure==
-		+	[[4gw6]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human_immunodeficiency_virus_type_1_(new_york-5_isolate) Human immunodeficiency virus type 1 (new york-5 isolate)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4GW6 OCA].
-	~~Description~~: ~~HIV~~-1 Integrase ~~Catalytic Core Domain Complexed with Allosteric Inhibitor~~	+	[[Category: Feng, L.]]
		+	[[Category: Kvaratskhelia, M.]]
		+	[[Category: Allosteric inhibitor]]
		+	[[Category: Dde motif]]
		+	[[Category: Hydrolase-hydrolase inhibitor complex]]
		+	[[Category: Integrase]]

OCA at 11:03, 23 January 2013

OCA — Wed, 23 Jan 2013 11:03:56 GMT

←Older revision		Revision as of 11:03, 23 January 2013
Line 1:		Line 1:
	'''Unreleased structure'''		'''Unreleased structure'''

-	The entry 4gw6 is ON HOLD	+	The entry 4gw6 is ON HOLD until Paper Publication

	Authors: Feng, L., Kvaratskhelia, M.		Authors: Feng, L., Kvaratskhelia, M.

	Description: HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor		Description: HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor

OCA at 06:55, 19 September 2012

OCA — Wed, 19 Sep 2012 06:55:03 GMT

←Older revision		Revision as of 06:55, 19 September 2012
Line 3:		Line 3:
	The entry 4gw6 is ON HOLD		The entry 4gw6 is ON HOLD

-	Authors: Feng,L, Kvaratskhelia, M	+	Authors: Feng, L., Kvaratskhelia, M.

	Description: HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor		Description: HIV-1 Integrase Catalytic Core Domain Complexed with Allosteric Inhibitor