4v1o

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<SX load='4v1o' size='340' side='right' viewer='molstar' caption='[[4v1o]], [[Resolution|resolution]] 9.70&Aring;' scene=''>
<SX load='4v1o' size='340' side='right' viewer='molstar' caption='[[4v1o]], [[Resolution|resolution]] 9.70&Aring;' scene=''>
== Structural highlights ==
== Structural highlights ==
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<table><tr><td colspan='2'>[[4v1o]] is a 26 chain structure with sequence from [http://en.wikipedia.org/wiki/As_2.2407 As 2.2407], [http://en.wikipedia.org/wiki/Atcc_18824 Atcc 18824] and [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4V1O OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=4V1O FirstGlance]. <br>
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<table><tr><td colspan='2'>[[4v1o]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4V1O OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4V1O FirstGlance]. <br>
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</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
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</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 9.7&#8491;</td></tr>
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<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4v1m|4v1m]], [[4v1n|4v1n]]</td></tr>
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<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
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<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/DNA-directed_RNA_polymerase DNA-directed RNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.6 2.7.7.6] </span></td></tr>
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<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4v1o FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4v1o OCA], [https://pdbe.org/4v1o PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4v1o RCSB], [https://www.ebi.ac.uk/pdbsum/4v1o PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4v1o ProSAT]</span></td></tr>
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<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=4v1o FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4v1o OCA], [http://pdbe.org/4v1o PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4v1o RCSB], [http://www.ebi.ac.uk/pdbsum/4v1o PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4v1o ProSAT]</span></td></tr>
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</table>
</table>
== Function ==
== Function ==
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[[http://www.uniprot.org/uniprot/RPB11_YEAST RPB11_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB11 is part of the core element with the central large cleft. Seems to be involved transcript termination. [[http://www.uniprot.org/uniprot/MED8_YEAST MED8_YEAST]] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins. MED8 binds to the consensus sequence 5'-[AC][AG]GAAAT-3' in both the UAS of SUC2 and the DRS2 of HXK2.<ref>PMID:9918841</ref> <ref>PMID:10526178</ref> <ref>PMID:11555651</ref> <ref>PMID:16076843</ref> <ref>PMID:16263706</ref> <ref>PMID:16885025</ref> [[http://www.uniprot.org/uniprot/RPB7_YEAST RPB7_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB7 is part of a subcomplex with RPB4 that binds to a pocket formed by RPB1, RPB2 and RPB6 at the base of the clamp element. The RBP4-RPB7 subcomplex seems to lock the clamp via RPB7 in the closed conformation thus preventing double stranded DNA to enter the active site cleft. The RPB4-RPB7 subcomplex binds single-stranded DNA and RNA. The RPB4-RPB7 subcomplex recruits FCP1 to Pol II.<ref>PMID:11087726</ref> <ref>PMID:15304220</ref> <ref>PMID:17875743</ref> [[http://www.uniprot.org/uniprot/MED22_YEAST MED22_YEAST]] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.<ref>PMID:16076843</ref> <ref>PMID:16263706</ref> <ref>PMID:16885025</ref> [[http://www.uniprot.org/uniprot/RPB2_YEAST RPB2_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Second largest component of RNA polymerases II which synthesizes mRNA precursors and many functional non-coding RNAs. Proposed to contribute to the polymerase catalytic activity and forms the polymerase active center together with the largest subunit. Pol II is the central component of the basal RNA polymerase II transcription machinery. During a transcription cycle, Pol II, general transcription factors and the Mediator complex assemble as the preinitiation complex (PIC) at the promoter. 11-15 base pairs of DNA surrounding the transcription start site are melted and the single stranded DNA template strand of the promoter is positioned deeply within the central active site cleft of Pol II to form the open complex. After synthesis of about 30 bases of RNA, Pol II releases its contacts with the core promoter and the rest of the transcription machinery (promoter clearance) and enters the stage of transcription elongation in which it moves on the template as the transcript elongates. Pol II appears to oscillate between inactive and active conformations at each step of nucleotide addition. Pol II is composed of mobile elements that move relative to each other. The core element with the central large cleft comprises RPB3, RBP10, RPB11, RPB12 and regions of RPB1 and RPB2 forming the active center. The clamp element (portions of RPB1, RPB2 and RPB3) is connected to the core through a set of flexible switches and moves to open and close the cleft. The cleft is surrounded by jaws: an upper jaw formed by portions of RBP1, RPB2 and RPB9, and a lower jaw. The jaws are thought to grab the incoming DNA template. The fork loop 1 (RPB2) interacts with the RNA-DNA hybrid, possibly stabilizing it. [[http://www.uniprot.org/uniprot/MED11_YEAST MED11_YEAST]] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex (PIC) with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins. The essential MED11/22 heterodimer specifically functions in promoting stable PIC formation.<ref>PMID:16076843</ref> <ref>PMID:16263706</ref> <ref>PMID:16885025</ref> <ref>PMID:18691966</ref> [[http://www.uniprot.org/uniprot/RPB1_YEAST RPB1_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Forms the polymerase active center together with the second largest subunit. Pol II is the central component of the basal RNA polymerase II transcription machinery. During a transcription cycle, Pol II, general transcription factors and the Mediator complex assemble as the preinitiation complex (PIC) at the promoter. 11-15 base pairs of DNA surrounding the transcription start site are melted and the single stranded DNA template strand of the promoter is positioned deeply within the central active site cleft of Pol II to form the open complex. After synthesis of about 30 bases of RNA, Pol II releases its contacts with the core promoter and the rest of the transcription machinery (promoter clearance) and enters the stage of transcription elongation in which it moves on the template as the transcript elongates. Pol II appears to oscillate between inactive and active conformations at each step of nucleotide addition. Elongation is influenced by the phosphorylation status of the C-terminal domain (CTD) of Pol II largest subunit (RPB1), which serves as a platform for assembly of factors that regulate transcription initiation, elongation, termination and mRNA processing. Pol II is composed of mobile elements that move relative to each other. The core element with the central large cleft comprises RPB3, RBP10, RPB11, RPB12 and regions of RPB1 and RPB2 forming the active center. The clamp element (portions of RPB1, RPB2 and RPB3) is connected to the core through a set of flexible switches and moves to open and close the cleft. A bridging helix emanates from RPB1 and crosses the cleft near the catalytic site and is thought to promote translocation of Pol II by acting as a ratchet that moves the RNA-DNA hybrid through the active site by switching from straight to bent conformations at each step of nucleotide addition. In elongating Pol II, the lid loop (RPB1) appears to act as a wedge to drive apart the DNA and RNA strands at the upstream end of the transcription bubble and guide the RNA strand toward the RNA exit groove located near the base of the largely unstructured CTD domain of RPB1. The rudder loop (RPB1) interacts with single stranded DNA after separation from the RNA strand, likely preventing reassociation with the exiting RNA. The cleft is surrounded by jaws: an upper jaw formed by portions of RBP1, RPB2 and RPB9, and a lower jaw, formed by RPB5 and portions of RBP1. The jaws are thought to grab the incoming DNA template, mainly by RPB5 direct contacts to DNA. [[http://www.uniprot.org/uniprot/T2FB_YEAST T2FB_YEAST]] TFIIF is a general transcription initiation factor that binds to RNA polymerase II. Its functions include the recruitment of RNA polymerase II to the promoter bound DNA-TBP-TFIIB complex, decreasing the affinity of RNA polymerase II for non-specific DNA, allowing for the subsequent recruitment of TFIIE and TFIIH, and facilitating RNA polymerase II elongation. TFG2 shows ATP-dependent DNA-helicase activity (By similarity). [[http://www.uniprot.org/uniprot/MED17_YEAST MED17_YEAST]] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.<ref>PMID:11555651</ref> <ref>PMID:16076843</ref> <ref>PMID:16263706</ref> <ref>PMID:16885025</ref> <ref>PMID:9845373</ref> [[http://www.uniprot.org/uniprot/TF2B_YEAST TF2B_YEAST]] General factor that plays a major role in the activation of eukaryotic genes transcribed by RNA polymerase II. [[http://www.uniprot.org/uniprot/RPAB2_YEAST RPAB2_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and small RNAs, such as 5S rRNA and tRNAs, respectively. Pol II is the central component of the basal RNA polymerase II transcription machinery. Pols are composed of mobile elements that move relative to each other. In Pol II, RPB6 is part of the clamp element and togther with parts of RPB1 and RPB2 forms a pocket to which the RPB4-RPB7 subcomplex binds (By similarity). [[http://www.uniprot.org/uniprot/MED20_YEAST MED20_YEAST]] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.<ref>PMID:16076843</ref> <ref>PMID:16109375</ref> <ref>PMID:16263706</ref> <ref>PMID:16885025</ref> [[http://www.uniprot.org/uniprot/RPB3_YEAST RPB3_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB3 is part of the core element with the central large cleft and the clamp element that moves to open and close the cleft. Seems to be involved in transcription termination. [[http://www.uniprot.org/uniprot/RPB9_YEAST RPB9_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB9 is part of the upper jaw surrounding the central large cleft and thought to grab the incoming DNA template. Involved in the regulation of transcription elongation. Involved in DNA repair of damage in the transcribed strand. Mediates a transcription-coupled repair (TCR) subpathway of nucleotide excision repair (NER).<ref>PMID:12411509</ref> [[http://www.uniprot.org/uniprot/RPAB4_YEAST RPAB4_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and a small RNAs, such as 5S rRNA and tRNAs, respectively. Pols are composed of mobile elements that move relative to each other. In Pol II, the core element with the central large cleft comprises RPB3, RBP10, RPB11, RPB12 and regions of RPB1 and RPB2 forming the active center. [[http://www.uniprot.org/uniprot/TBP_YEAST TBP_YEAST]] General transcription factor that functions at the core of the DNA-binding general transcription factor complex TFIID. Binding of TFIID to a promoter (with or without TATA element) is the initial step in preinitiation complex (PIC) formation. TFIID plays a key role in the regulation of gene expression by RNA polymerase II through different activities such as transcription activator interaction, core promoter recognition and selectivity, TFIIA and TFIIB interaction, chromatin modification (histone acetylation by TAF1), facilitation of DNA opening and initiation of transcription.<ref>PMID:9618449</ref> <ref>PMID:12138208</ref> <ref>PMID:12516863</ref> [[http://www.uniprot.org/uniprot/RPAB3_YEAST RPAB3_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and small RNAs, such as 5S rRNA and tRNAs, respectively. [[http://www.uniprot.org/uniprot/RPB4_YEAST RPB4_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB4 is part of a subcomplex with RPB7 that binds to a pocket formed by RPB1, RPB2 and RPB6 at the base of the clamp element. The RBP4-RPB7 subcomplex seems to lock the clamp via RPB7 in the closed conformation thus preventing double stranded DNA to enter the active site cleft. The RPB4-RPB7 subcomplex binds single-stranded DNA and RNA. The RPB4-RPB7 subcomplex is necessary for promoter-directed transcription initiation but is not required for recruitment of Pol II to active preinitiation complexes and seems to be dispensable for transcription elongation and termination. The RPB4-RPB7 subcomplex recruits FCP1 to Pol II. Involved in DNA repair of damage in the transcribed strand. RPB4 is dispensable under optimal growth conditions, but becomes essential during heat or cold shock and under nutrient depletion. Suppresses the RBP9-mediated transcription-coupled repair (TCR) subpathway of nucleotide excision repair (NER) but facilitates the RAD26-mediated TCR subpathway. Under stress conditions only, involved in mRNA export to the cytoplasm. Involved in mRNA decay. Promotes or enhances the deadenylation process of specific mRNAs and may recruit PAT1 and the LSM1-7 complex to these mRNAs, thus stimulating their decapping and further decay.<ref>PMID:1985924</ref> <ref>PMID:11087726</ref> <ref>PMID:11382749</ref> <ref>PMID:12411509</ref> <ref>PMID:12857861</ref> <ref>PMID:15304220</ref> <ref>PMID:16357218</ref> [[http://www.uniprot.org/uniprot/MED18_YEAST MED18_YEAST]] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.<ref>PMID:9845373</ref> <ref>PMID:11555651</ref> <ref>PMID:16076843</ref> <ref>PMID:16109375</ref> <ref>PMID:16263706</ref> <ref>PMID:16885025</ref> [[http://www.uniprot.org/uniprot/RPAB5_YEAST RPAB5_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and a small RNAs, such as 5S rRNA and tRNAs, respectively. Pol II is the central component of the basal RNA polymerase II transcription machinery. Pols are composed of mobile elements that move relative to each other. In Pol II, RBP10 is part of the core element with the central large cleft. [[http://www.uniprot.org/uniprot/MED6_YEAST MED6_YEAST]] Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.<ref>PMID:16076843</ref> <ref>PMID:16263706</ref> <ref>PMID:16885025</ref> <ref>PMID:9234719</ref> <ref>PMID:9845373</ref> [[http://www.uniprot.org/uniprot/RPAB1_YEAST RPAB1_YEAST]] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and small RNAs, such as 5S rRNA and tRNAs, respectively. Pol II is the central component of the basal RNA polymerase II transcription machinery. Pols are composed of mobile elements that move relative to each other. In Pol II, RPB5 is part of the lower jaw surrounding the central large cleft and thought to grab the incoming DNA template. Seems to be the major component in this process (By similarity).
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[https://www.uniprot.org/uniprot/RPB1_YEAST RPB1_YEAST] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Forms the polymerase active center together with the second largest subunit. Pol II is the central component of the basal RNA polymerase II transcription machinery. During a transcription cycle, Pol II, general transcription factors and the Mediator complex assemble as the preinitiation complex (PIC) at the promoter. 11-15 base pairs of DNA surrounding the transcription start site are melted and the single stranded DNA template strand of the promoter is positioned deeply within the central active site cleft of Pol II to form the open complex. After synthesis of about 30 bases of RNA, Pol II releases its contacts with the core promoter and the rest of the transcription machinery (promoter clearance) and enters the stage of transcription elongation in which it moves on the template as the transcript elongates. Pol II appears to oscillate between inactive and active conformations at each step of nucleotide addition. Elongation is influenced by the phosphorylation status of the C-terminal domain (CTD) of Pol II largest subunit (RPB1), which serves as a platform for assembly of factors that regulate transcription initiation, elongation, termination and mRNA processing. Pol II is composed of mobile elements that move relative to each other. The core element with the central large cleft comprises RPB3, RBP10, RPB11, RPB12 and regions of RPB1 and RPB2 forming the active center. The clamp element (portions of RPB1, RPB2 and RPB3) is connected to the core through a set of flexible switches and moves to open and close the cleft. A bridging helix emanates from RPB1 and crosses the cleft near the catalytic site and is thought to promote translocation of Pol II by acting as a ratchet that moves the RNA-DNA hybrid through the active site by switching from straight to bent conformations at each step of nucleotide addition. In elongating Pol II, the lid loop (RPB1) appears to act as a wedge to drive apart the DNA and RNA strands at the upstream end of the transcription bubble and guide the RNA strand toward the RNA exit groove located near the base of the largely unstructured CTD domain of RPB1. The rudder loop (RPB1) interacts with single stranded DNA after separation from the RNA strand, likely preventing reassociation with the exiting RNA. The cleft is surrounded by jaws: an upper jaw formed by portions of RBP1, RPB2 and RPB9, and a lower jaw, formed by RPB5 and portions of RBP1. The jaws are thought to grab the incoming DNA template, mainly by RPB5 direct contacts to DNA.
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== Publication Abstract from PubMed ==
== Publication Abstract from PubMed ==
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__TOC__
__TOC__
</SX>
</SX>
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[[Category: As 2 2407]]
 
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[[Category: Atcc 18824]]
 
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[[Category: DNA-directed RNA polymerase]]
 
[[Category: Large Structures]]
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae]]
[[Category: Saccharomyces cerevisiae]]
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[[Category: Baumeister, W]]
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[[Category: Baumeister W]]
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[[Category: Borchers, C H]]
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[[Category: Borchers CH]]
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[[Category: Cramer, P]]
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[[Category: Cramer P]]
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[[Category: Hemann, M]]
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[[Category: Hemann M]]
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[[Category: Herzog, F]]
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[[Category: Herzog F]]
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[[Category: Lariviere, L]]
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[[Category: Lariviere L]]
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[[Category: Petrotchenko, E V]]
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[[Category: Petrotchenko EV]]
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[[Category: Plaschka, C]]
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[[Category: Plaschka C]]
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[[Category: Tegunov, D]]
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[[Category: Tegunov D]]
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[[Category: Villa, E]]
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[[Category: Villa E]]
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[[Category: Wenzeck, L]]
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[[Category: Wenzeck L]]
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[[Category: General transcription factor]]
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[[Category: Rna polymerase ii]]
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[[Category: Transcription]]
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[[Category: Transcription initiation]]
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Current revision

Architecture of the RNA polymerase II-Mediator core transcription initiation complex

4v1o, resolution 9.70Å

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