View source for 1hr0


==CRYSTAL STRUCTURE OF INITIATION FACTOR IF1 BOUND TO THE 30S RIBOSOMAL SUBUNIT==
<StructureSection load='1hr0' size='340' side='right' caption='[[1hr0]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1hr0]] is a 23 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895] and [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HR0 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1HR0 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><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">[[1qd7|1qd7]], [[1fjf|1fjf]], [[1fjg|1fjg]]</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=1hr0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hr0 OCA], [http://pdbe.org/1hr0 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1hr0 RCSB], [http://www.ebi.ac.uk/pdbsum/1hr0 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1hr0 ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/RS10_THETH RS10_THETH]] Involved in the binding of tRNA to the ribosomes (By similarity). [[http://www.uniprot.org/uniprot/RS6_THETH RS6_THETH]] Located on the outer edge of the platform on the body of the 30S subunit (By similarity). [[http://www.uniprot.org/uniprot/RSHX_THETH RSHX_THETH]] Binds at the top of the head of the 30S subunit. It stabilizes a number of different RNA elements and thus is important for subunit structure (By similarity). [[http://www.uniprot.org/uniprot/RS15_THETH RS15_THETH]] One of the primary rRNA binding proteins, it binds directly to 16S rRNA where it helps nucleate assembly of the platform of the 30S subunit by binding and bridging several RNA helices of the 16S rRNA.  Forms an intersubunit bridge (bridge B4) with the 23S rRNA of the 50S subunit in the ribosome (By similarity). [[http://www.uniprot.org/uniprot/RS12_THETH RS12_THETH]] With S4 and S5 plays an important role in translational accuracy (By similarity).[HAMAP-Rule:MF_00403_B]  Interacts with and stabilizes bases of the 16S rRNA that are involved in tRNA selection in the A site and with the mRNA backbone. Located at the interface of the 30S and 50S subunits, it traverses the body of the 30S subunit contacting proteins on the other side and probably holding the rRNA structure together. The combined cluster of proteins S8, S12 and S17 appears to hold together the shoulder and platform of the 30S subunit (By similarity).[HAMAP-Rule:MF_00403_B] [[http://www.uniprot.org/uniprot/RS5_THETH RS5_THETH]] With S4 and S12 plays an important role in translational accuracy (By similarity).[HAMAP-Rule:MF_01307_B]  Located at the back of the 30S subunit body where it stabilizes the conformation of the head with respect to the body (By similarity).[HAMAP-Rule:MF_01307_B] [[http://www.uniprot.org/uniprot/RS8_THETH RS8_THETH]] One of the primary rRNA binding proteins, it binds directly to 16S rRNA central domain where it helps coordinate assembly of the platform of the 30S subunit (By similarity). [[http://www.uniprot.org/uniprot/RS19_THETH RS19_THETH]] Protein S19 forms a complex with S13 that binds strongly to the 16S ribosomal RNA (By similarity). [[http://www.uniprot.org/uniprot/RS14Z_THETH RS14Z_THETH]] Binds 16S rRNA, required for the assembly of 30S particles and may also be responsible for determining the conformation of the 16S rRNA at the A site (By similarity). [[http://www.uniprot.org/uniprot/RS7_THET8 RS7_THET8]] One of the primary rRNA binding proteins, it binds directly to 3'-end of the 16S rRNA where it nucleates assembly of the head domain of the 30S subunit. Is located at the subunit interface close to the decoding center. Binds mRNA and the E site tRNA blocking its exit path in the ribosome. This blockage implies that this section of the ribosome must be able to move to release the deacetylated tRNA.[HAMAP-Rule:MF_00480_B] [[http://www.uniprot.org/uniprot/RS4_THET8 RS4_THET8]] One of the primary rRNA binding proteins, it binds directly to 16S rRNA where it helps nucleate assembly of the body and platform of the 30S subunit. Binds mRNA in the 70S ribosome, positioning it for translation.[HAMAP-Rule:MF_01306_B] 
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/hr/1hr0_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1hr0 ConSurf].
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== Publication Abstract from PubMed ==
Initiation of translation at the correct position on messenger RNA is essential for accurate protein synthesis. In prokaryotes, this process requires three initiation factors: IF1, IF2, and IF3. Here we report the crystal structure of a complex of IF1 and the 30S ribosomal subunit. Binding of IF1 occludes the ribosomal A site and flips out the functionally important bases A1492 and A1493 from helix 44 of 16S RNA, burying them in pockets in IF1. The binding of IF1 causes long-range changes in the conformation of H44 and leads to movement of the domains of 30S with respect to each other. The structure explains how localized changes at the ribosomal A site lead to global alterations in the conformation of the 30S subunit.

Crystal structure of an initiation factor bound to the 30S ribosomal subunit.,Carter AP, Clemons WM Jr, Brodersen DE, Morgan-Warren RJ, Hartsch T, Wimberly BT, Ramakrishnan V Science. 2001 Jan 19;291(5503):498-501. PMID:11228145<ref>PMID:11228145</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1hr0" style="background-color:#fffaf0;"></div>

==See Also==
*[[Ribosome 3D structures|Ribosome 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bacillus coli migula 1895]]
[[Category: Thermus thermophilus]]
[[Category: Brodersen, D E]]
[[Category: Carter, A P]]
[[Category: Clemons, W M]]
[[Category: Morgan-Warren, R J]]
[[Category: Ramakrishnan, V]]
[[Category: Wimberly, B T]]
[[Category: If1]]
[[Category: Initiation factor]]
[[Category: Ribosomal subunit]]
[[Category: Ribosome]]