6jly: Difference between revisions

<table><tr><td colspan='2'>[[6jly]] is a 12 chain structure with sequence from [http://en.wikipedia.org/wiki/Baker's_yeast Baker's yeast] and [http://en.wikipedia.org/wiki/Fission_yeast Fission yeast]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6JLY OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6JLY FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">tif221, SPCC11E10.07c ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=284812 Fission yeast]), tif222, SPAC343.14c ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=284812 Fission yeast]), tif223, SPAC4D7.09 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=284812 Fission yeast]), tif224, SPAC21E11.06 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=284812 Fission yeast]), tif225, SPAC8C9.15c ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=284812 Fission yeast]), SUI2, TIF211, YJR007W, J1429 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=559292 Baker's yeast])</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=6jly FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6jly OCA], [http://pdbe.org/6jly PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6jly RCSB], [http://www.ebi.ac.uk/pdbsum/6jly PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6jly ProSAT]</span></td></tr>

[[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/EI2BD_SCHPO EI2BD_SCHPO]] Catalyzes the exchange of eukaryotic initiation factor 2-bound GDP for GTP. [[http://www.uniprot.org/uniprot/EI2BA_SCHPO EI2BA_SCHPO]] Catalyzes the exchange of eukaryotic initiation factor 2-bound GDP for GTP. [[http://www.uniprot.org/uniprot/EI2BG_SCHPO EI2BG_SCHPO]] Catalyzes the exchange of eukaryotic initiation factor 2-bound GDP for GTP. [[http://www.uniprot.org/uniprot/EI2BB_SCHPO EI2BB_SCHPO]] Catalyzes the exchange of eukaryotic initiation factor 2-bound GDP for GTP. [[http://www.uniprot.org/uniprot/EI2BE_SCHPO EI2BE_SCHPO]] Subunit of the guanine nucleotide exchange factor for eIF-2.

A core event in the integrated stress response, an adaptive pathway common to all eukaryotic cells in response to various stress stimuli, is the phosphorylation of eukaryotic translation initiation factor 2 (eIF2). Normally, unphosphorylated eIF2 transfers the methionylated initiator tRNA to the ribosome in a guanosine 5'-triphosphate-dependent manner. By contrast, phosphorylated eIF2 inhibits its specific guanine nucleotide exchange factor, eIF2B. To elucidate how the eIF2 phosphorylation status regulates the eIF2B activity, we determined cryo-electron microscopic and crystallographic structures of eIF2B in complex with unphosphorylated or phosphorylated eIF2. The unphosphorylated and phosphorylated forms of eIF2 bind to eIF2B in completely different manners: the nucleotide exchange-active and -inactive modes, respectively. These structures explain how phosphorylated eIF2 dominantly inhibits the nucleotide exchange activity of eIF2B.

 

== References ==

[[Category: Ito, T]]

[[Category: Kashiwagi, K]]

[[Category: Translation]]

[[Category: Translation initiation]]