5aby
From Proteopedia
(Difference between revisions)
| Line 1: | Line 1: | ||
| - | ''' | + | ==Complex of C. elegans eIF4E-3 with the 4E-binding protein Mextli== |
| + | <StructureSection load='5aby' size='340' side='right' caption='[[5aby]], [[Resolution|resolution]] 1.95Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[5aby]] is a 6 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5ABY OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5ABY FirstGlance]. <br> | ||
| + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> | ||
| + | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5abu|5abu]], [[5abv|5abv]], [[5abx|5abx]]</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=5aby FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5aby OCA], [http://www.rcsb.org/pdb/explore.do?structureId=5aby RCSB], [http://www.ebi.ac.uk/pdbsum/5aby PDBsum]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [[http://www.uniprot.org/uniprot/IF4E3_CAEEL IF4E3_CAEEL]] Recognizes and binds the 7-methylguanosine-containing mRNA cap during an early step in the initiation of protein synthesis and facilitates ribosome binding by inducing the unwinding of the mRNAs secondary structures. All 5 eIF4E proteins bind monomethyl cap structures. Only ife-1, ife-2 and ife-5 bind trimethyl cap structures which result from trans-splicing. Translation of trimethyl cap structure mRNAs may be regulated by intracellular redox state; disulfide bonds change the width and depth of the cap-binding cavity determining selectivity to mRNA caps. Ife-3 is essential for viability.<ref>PMID:10744754</ref> <ref>PMID:12422237</ref> <ref>PMID:9553113</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | The eIF4E-binding proteins (4E-BPs) are a diverse class of translation regulators that share a canonical eIF4E-binding motif (4E-BM) with eIF4G. Consequently, they compete with eIF4G for binding to eIF4E, thereby inhibiting translation initiation. Mextli (Mxt) is an unusual 4E-BP that promotes translation by also interacting with eIF3. Here we present the crystal structures of the eIF4E-binding regions of the Drosophila melanogaster (Dm) and Caenorhabditis elegans (Ce) Mxt proteins in complex with eIF4E in the cap-bound and cap-free states. The structures reveal unexpected evolutionary plasticity in the eIF4E-binding mode, with a classical bipartite interface for Ce Mxt and a novel tripartite interface for Dm Mxt. Both interfaces comprise a canonical helix and a noncanonical helix that engage the dorsal and lateral surfaces of eIF4E, respectively. Remarkably, Dm Mxt contains a C-terminal auxiliary helix that lies anti-parallel to the canonical helix on the eIF4E dorsal surface. In contrast to the eIF4G and Ce Mxt complexes, the Dm eIF4E-Mxt complexes are resistant to competition by bipartite 4E-BPs, suggesting that Dm Mxt can bind eIF4E when eIF4G binding is inhibited. Our results uncovered unexpected diversity in the binding modes of 4E-BPs, resulting in eIF4E complexes that display differential sensitivity to 4E-BP regulation. | ||
| - | + | Mextli proteins use both canonical bipartite and novel tripartite binding modes to form eIF4E complexes that display differential sensitivity to 4E-BP regulation.,Peter D, Weber R, Kone C, Chung MY, Ebertsch L, Truffault V, Weichenrieder O, Igreja C, Izaurralde E Genes Dev. 2015 Aug 20. PMID:26294658<ref>PMID:26294658</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | == References == | |
| - | + | <references/> | |
| + | __TOC__ | ||
| + | </StructureSection> | ||
[[Category: Peter, D]] | [[Category: Peter, D]] | ||
[[Category: Weichenrieder, O]] | [[Category: Weichenrieder, O]] | ||
| + | [[Category: 4e binding protein]] | ||
| + | [[Category: Cap binding protein]] | ||
| + | [[Category: Gene regulation]] | ||
| + | [[Category: Translation]] | ||
Revision as of 12:22, 2 September 2015
Complex of C. elegans eIF4E-3 with the 4E-binding protein Mextli
| |||||||||||
