3j81 - Revision history

OCA at 10:11, 21 February 2024

OCA — Wed, 21 Feb 2024 10:11:14 GMT

←Older revision		Revision as of 10:11, 21 February 2024
Line 10:		Line 10:
	== Function ==		== Function ==
	[https://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits.		[https://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits.
-	<div style="background-color:#fffaf0;">
-	== Publication Abstract from PubMed ==
-	During eukaryotic translation initiation, initiator tRNA does not insert fully into the P decoding site on the 40S ribosomal subunit. This conformation (POUT) is compatible with scanning mRNA for the AUG start codon. Base pairing with AUG is thought to promote isomerization to a more stable conformation (PIN) that arrests scanning and promotes dissociation of eIF1 from the 40S subunit. Here, we present a cryoEM reconstruction of a yeast preinitiation complex at 4.0 A resolution with initiator tRNA in the PIN state, prior to eIF1 release. The structure reveals stabilization of the codon-anticodon duplex by the N-terminal tail of eIF1A, changes in the structure of eIF1 likely instrumental in its subsequent release, and changes in the conformation of eIF2. The mRNA traverses the entire mRNA cleft and makes connections to the regulatory domain of eIF2?, eIF1A, and ribosomal elements that allow recognition of context nucleotides surrounding the AUG codon.
-
-	Structural changes enable start codon recognition by the eukaryotic translation initiation complex.,Hussain T, Llacer JL, Fernandez IS, Munoz A, Martin-Marcos P, Savva CG, Lorsch JR, Hinnebusch AG, Ramakrishnan V Cell. 2014 Oct 23;159(3):597-607. doi: 10.1016/j.cell.2014.10.001. Epub 2014 Oct , 16. PMID:25417110<ref>PMID:25417110</ref>
-
-	From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
-	</div>
-	<div class="pdbe-citations 3j81" style="background-color:#fffaf0;"></div>

	==See Also==		==See Also==
	*[[Eukaryotic initiation factor 3D structures\|Eukaryotic initiation factor 3D structures]]		*[[Eukaryotic initiation factor 3D structures\|Eukaryotic initiation factor 3D structures]]
-	== References ==
-	<references/>
	__TOC__		__TOC__
	</SX>		</SX>

OCA at 14:17, 24 January 2024

OCA — Wed, 24 Jan 2024 14:17:46 GMT

←Older revision		Revision as of 14:17, 24 January 2024
Line 3:		Line 3:
	<SX load='3j81' size='340' side='right' viewer='molstar' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>		<SX load='3j81' size='340' side='right' viewer='molstar' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>
	== Structural highlights ==		== Structural highlights ==
-	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from ~~[https://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and~~ [https://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3J81 FirstGlance]. <br>	+	<table><tr><td colspan='2'>[[3j81]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3J81 FirstGlance]. <br>
-	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene~~></td></tr>~~	+	</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models\|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution\|Resolution]] 4Å</td></tr>
-	~~<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[3j80\|3j80]]</div~~></td></tr>	+	<tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [https://pdbe.org/3j81 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [https://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [https://pdbe.org/3j81 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [https://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 ProSAT]</span></td></tr>
	</table>		</table>
	== Function ==		== Function ==
-	[[https://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[https://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[https://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[https://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[https://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[https://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[https://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[https://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.	+	[https://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits.
	<div style="background-color:#fffaf0;">		<div style="background-color:#fffaf0;">
	== Publication Abstract from PubMed ==		== Publication Abstract from PubMed ==
Line 26:		Line 26:
	__TOC__		__TOC__
	</SX>		</SX>
-	[[Category: Atcc 56498]]
	[[Category: Kluyveromyces lactis]]		[[Category: Kluyveromyces lactis]]
	[[Category: Large Structures]]		[[Category: Large Structures]]
-	[[Category: Fernandez~~, I S~~]]	+	[[Category: Fernandez IS]]
-	[[Category: Hussain, T]]	+	[[Category: Hussain T]]
-	[[Category: Llacer~~, J L~~]]	+	[[Category: Llacer JL]]
-	[[Category: Ramakrishnan, V]]	+	[[Category: Ramakrishnan V]]
-	[[Category: Savva~~, C G]]~~	+	[[Category: Savva CG]]
-	~~[[Category: Eukaryotic translation initiation]]~~	+
-	~~[[Category: Ribosome]]~~	+
-	~~[[Category: Small ribosome subunit~~]]	+

OCA at 03:51, 21 April 2022

OCA — Thu, 21 Apr 2022 03:51:48 GMT

←Older revision		Revision as of 03:51, 21 April 2022
Line 3:		Line 3:
	<SX load='3j81' size='340' side='right' viewer='molstar' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>		<SX load='3j81' size='340' side='right' viewer='molstar' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>
	== Structural highlights ==		== Structural highlights ==
-	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [~~http~~://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and [~~http~~://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [~~http~~://proteopedia.org/fgij/fg.htm?mol=3J81 FirstGlance]. <br>	+	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [https://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and [https://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3J81 FirstGlance]. <br>
	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>		</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
-	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</td></tr>	+	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[3j80\|3j80]]</div></td></tr>
-	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[~~http~~://proteopedia.org/fgij/fg.htm?mol=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [~~http~~://pdbe.org/3j81 PDBe], [~~http~~://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [~~http~~://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [~~http~~://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [https://pdbe.org/3j81 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [https://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 ProSAT]</span></td></tr>
	</table>		</table>
	== Function ==		== Function ==
-	[[~~http~~://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[~~http~~://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[~~http~~://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[~~http~~://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[~~http~~://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[~~http~~://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[~~http~~://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[~~http~~://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.	+	[[https://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[https://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[https://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[https://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[https://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[https://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[https://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[https://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.
	<div style="background-color:#fffaf0;">		<div style="background-color:#fffaf0;">
	== Publication Abstract from PubMed ==		== Publication Abstract from PubMed ==

OCA at 18:07, 10 April 2020

OCA — Fri, 10 Apr 2020 18:07:48 GMT

←Older revision		Revision as of 18:07, 10 April 2020
Line 3:		Line 3:
	<SX load='3j81' size='340' side='right' viewer='molstar' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>		<SX load='3j81' size='340' side='right' viewer='molstar' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>
	== Structural highlights ==		== Structural highlights ==
-	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and [http://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [http://~~oca~~.~~weizmann.ac.il/oca-docs~~/fgij/fg.htm?mol=3J81 FirstGlance]. <br>	+	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and [http://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=3J81 FirstGlance]. <br>
-	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>	+	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</td></tr>		<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://pdbe.org/3j81 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 ProSAT]</span></td></tr>	+	<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://pdbe.org/3j81 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 ProSAT]</span></td></tr>
	</table>		</table>
	== Function ==		== Function ==

OCA at 17:29, 6 March 2020

OCA — Fri, 06 Mar 2020 17:29:10 GMT

←Older revision		Revision as of 17:29, 6 March 2020
Line 1:		Line 1:
-	~~{{Large structure}}~~	+
	==CryoEM structure of a partial yeast 48S preinitiation complex==		==CryoEM structure of a partial yeast 48S preinitiation complex==
-	<~~StructureSection~~ load='3j81' size='340' side='right' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>	+	<SX load='3j81' size='340' side='right' viewer='molstar' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>
	== Structural highlights ==		== Structural highlights ==
	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and [http://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3J81 FirstGlance]. <br>		<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and [http://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3J81 FirstGlance]. <br>
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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://pdbe.org/3j81 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 ProSAT]</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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://pdbe.org/3j81 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 ProSAT]</span></td></tr>
	</table>		</table>
-	{{Large structure}}
	== Function ==		== Function ==
	[[http://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[http://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[http://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[http://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[http://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.		[[http://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[http://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[http://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[http://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[http://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.
Line 22:		Line 21:

	==See Also==		==See Also==
-	*[[Eukaryotic initiation factor\|Eukaryotic initiation factor]]	+	*[[Eukaryotic initiation factor 3D structures\|Eukaryotic initiation factor 3D structures]]
	== References ==		== References ==
	<references/>		<references/>
	__TOC__		__TOC__
-	</~~StructureSection~~>	+	</SX>
	[[Category: Atcc 56498]]		[[Category: Atcc 56498]]
	[[Category: Kluyveromyces lactis]]		[[Category: Kluyveromyces lactis]]
		+	[[Category: Large Structures]]
	[[Category: Fernandez, I S]]		[[Category: Fernandez, I S]]
	[[Category: Hussain, T]]		[[Category: Hussain, T]]

OCA at 08:17, 18 July 2018

OCA — Wed, 18 Jul 2018 08:17:07 GMT

←Older revision		Revision as of 08:17, 18 July 2018
Line 3:		Line 3:
	<StructureSection load='3j81' size='340' side='right' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>		<StructureSection load='3j81' size='340' side='right' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>
	== Structural highlights ==		== Structural highlights ==
-	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [http://en.wikipedia.org/wiki/ ] and [http://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3J81 FirstGlance]. <br>	+	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_56498 Atcc 56498] and [http://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3J81 FirstGlance]. <br>
	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>		</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</td></tr>		<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</td></tr>
Line 27:		Line 27:
	__TOC__		__TOC__
	</StructureSection>		</StructureSection>
		+	[[Category: Atcc 56498]]
	[[Category: Kluyveromyces lactis]]		[[Category: Kluyveromyces lactis]]
	[[Category: Fernandez, I S]]		[[Category: Fernandez, I S]]

OCA at 19:35, 4 August 2016

OCA — Thu, 04 Aug 2016 19:35:29 GMT

←Older revision		Revision as of 19:35, 4 August 2016
Line 1:		Line 1:
		+	{{Large structure}}
	==CryoEM structure of a partial yeast 48S preinitiation complex==		==CryoEM structure of a partial yeast 48S preinitiation complex==
	<StructureSection load='3j81' size='340' side='right' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>		<StructureSection load='3j81' size='340' side='right' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>
Line 5:		Line 6:
	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>		</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</td></tr>		<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://pdbe.org/3j81 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3j81 ProSAT]</span></td></tr>
	</table>		</table>
		+	{{Large structure}}
	== Function ==		== Function ==
	[[http://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[http://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[http://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[http://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[http://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.		[[http://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[http://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[http://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[http://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[http://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.
Line 17:		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 3j81" style="background-color:#fffaf0;"></div>
		+
		+	==See Also==
		+	*[[Eukaryotic initiation factor\|Eukaryotic initiation factor]]
	== References ==		== References ==
	<references/>		<references/>

OCA at 10:50, 24 December 2014

OCA — Wed, 24 Dec 2014 10:50:24 GMT

←Older revision		Revision as of 10:50, 24 December 2014
Line 7:		Line 7:
	<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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 PDBsum]</span></td></tr>
	</table>		</table>
		+	== Function ==
		+	[[http://www.uniprot.org/uniprot/RSSA_KLULA RSSA_KLULA]] Required for the assembly and/or stability of the 40S ribosomal subunit. Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. [[http://www.uniprot.org/uniprot/SUI1_YEAST SUI1_YEAST]] Additional factor that functions in concert with eIF-2 and the initiator tRNA in directing the ribosome to the proper start site of translation. [[http://www.uniprot.org/uniprot/RS27A_KLULA RS27A_KLULA]] Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, and DNA-damage responses. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity). Ribosomal protein S27a is a component of the 40S subunit of the ribosome. [[http://www.uniprot.org/uniprot/IF2B_YEAST IF2B_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/RS21_KLULA RS21_KLULA]] Required for the processing of the 20S rRNA-precursor to mature 18S rRNA in a late step of the maturation of 40S ribosomal subunits. Has a physiological role leading to 18S rRNA stability (By similarity). [[http://www.uniprot.org/uniprot/IF2A_YEAST IF2A_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF2G_YEAST IF2G_YEAST]] eIF-2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA. This complex binds to a 40S ribosomal subunit, followed by mRNA binding to form a 43S preinitiation complex. Junction of the 60S ribosomal subunit to form the 80S initiation complex is preceded by hydrolysis of the GTP bound to eIF-2 and release of an eIF-2-GDP binary complex. In order for eIF-2 to recycle and catalyze another round of initiation, the GDP bound to eIF-2 must exchange with GTP by way of a reaction catalyzed by eIF-2B. [[http://www.uniprot.org/uniprot/IF1A_YEAST IF1A_YEAST]] Seems to be required for maximal rate of protein biosynthesis. Enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(I) to 40 S ribosomal subunits.
		+	<div style="background-color:#fffaf0;">
		+	== Publication Abstract from PubMed ==
		+	During eukaryotic translation initiation, initiator tRNA does not insert fully into the P decoding site on the 40S ribosomal subunit. This conformation (POUT) is compatible with scanning mRNA for the AUG start codon. Base pairing with AUG is thought to promote isomerization to a more stable conformation (PIN) that arrests scanning and promotes dissociation of eIF1 from the 40S subunit. Here, we present a cryoEM reconstruction of a yeast preinitiation complex at 4.0 A resolution with initiator tRNA in the PIN state, prior to eIF1 release. The structure reveals stabilization of the codon-anticodon duplex by the N-terminal tail of eIF1A, changes in the structure of eIF1 likely instrumental in its subsequent release, and changes in the conformation of eIF2. The mRNA traverses the entire mRNA cleft and makes connections to the regulatory domain of eIF2?, eIF1A, and ribosomal elements that allow recognition of context nucleotides surrounding the AUG codon.
		+
		+	Structural changes enable start codon recognition by the eukaryotic translation initiation complex.,Hussain T, Llacer JL, Fernandez IS, Munoz A, Martin-Marcos P, Savva CG, Lorsch JR, Hinnebusch AG, Ramakrishnan V Cell. 2014 Oct 23;159(3):597-607. doi: 10.1016/j.cell.2014.10.001. Epub 2014 Oct , 16. PMID:25417110<ref>PMID:25417110</ref>
		+
		+	From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
		+	</div>
		+	== References ==
		+	<references/>
	__TOC__		__TOC__
	</StructureSection>		</StructureSection>

OCA at 09:39, 19 November 2014

OCA — Wed, 19 Nov 2014 09:39:20 GMT

←Older revision		Revision as of 09:39, 19 November 2014
Line 10:		Line 10:
	</StructureSection>		</StructureSection>
	[[Category: Kluyveromyces lactis]]		[[Category: Kluyveromyces lactis]]
-	[[Category: Fernandez, I S.]]	+	[[Category: Fernandez, I S]]
-	[[Category: Hussain, T.]]	+	[[Category: Hussain, T]]
-	[[Category: Llacer, J L.]]	+	[[Category: Llacer, J L]]
-	[[Category: Ramakrishnan, V.]]	+	[[Category: Ramakrishnan, V]]
-	[[Category: Savva, C G~~.]]~~	+	[[Category: Savva, C G]]
-	~~[[Category: 48~~]]	+
	[[Category: Eukaryotic translation initiation]]		[[Category: Eukaryotic translation initiation]]
	[[Category: Ribosome]]		[[Category: Ribosome]]
	[[Category: Small ribosome subunit]]		[[Category: Small ribosome subunit]]

OCA at 08:53, 5 November 2014

OCA — Wed, 05 Nov 2014 08:53:29 GMT

←Older revision		Revision as of 08:53, 5 November 2014
Line 1:		Line 1:
-	'''~~Unreleased structure~~'''	+	==CryoEM structure of a partial yeast 48S preinitiation complex==
-		+	<StructureSection load='3j81' size='340' side='right' caption='[[3j81]], [[Resolution\|resolution]] 4.00Å' scene=''>
-	~~The entry~~ 3j81 is ~~ON HOLD until Paper Publication~~	+	== Structural highlights ==
-		+	<table><tr><td colspan='2'>[[3j81]] is a 42 chain structure with sequence from [http://en.wikipedia.org/wiki/ ] and [http://en.wikipedia.org/wiki/Kluyveromyces_lactis Kluyveromyces lactis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3J81 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3J81 FirstGlance]. <br>
-	~~Authors~~: ~~Hussain, T~~., ~~Llacer~~, J.L., Fernandez, I.S., ~~Savva, C.G~~., Ramakrishnan, V.	+	</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand\|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
-		+	<tr id='related'><td class="sblockLbl"><b>[[Related_structure\|Related:]]</b></td><td class="sblockDat">[[3j80\|3j80]]</td></tr>
-	~~Description~~: ~~CryoEM structure of a partial yeast 48S preinitiation complex~~	+	<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=3j81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3j81 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3j81 RCSB], [http://www.ebi.ac.uk/pdbsum/3j81 PDBsum]</span></td></tr>
		+	</table>
		+	__TOC__
		+	</StructureSection>
		+	[[Category: Kluyveromyces lactis]]
		+	[[Category: Fernandez, I S.]]
		+	[[Category: Hussain, T.]]
		+	[[Category: Llacer, J L.]]
		+	[[Category: Ramakrishnan, V.]]
		+	[[Category: Savva, C G.]]
		+	[[Category: 48]]
		+	[[Category: Eukaryotic translation initiation]]
		+	[[Category: Ribosome]]
		+	[[Category: Small ribosome subunit]]