View source for 8ucy


==Sterile Alpha Motif (SAM) domain from Tric1, Arabidopsis thaliana==
<StructureSection load='8ucy' size='340' side='right'caption='[[8ucy]], [[Resolution|resolution]] 1.48&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8ucy]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8UCY OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8UCY FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.48&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</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=8ucy FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8ucy OCA], [https://pdbe.org/8ucy PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8ucy RCSB], [https://www.ebi.ac.uk/pdbsum/8ucy PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8ucy ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/HP301_ARATH HP301_ARATH] Together with HP30-2 and HP20, triggers the import and insertion of transit sequence-less multi-pass transmembrane proteins (e.g. CEQORH) into the chloroplastic inner membrane.<ref>PMID:24248378</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Mitochondria are membrane-bound organelles of endosymbiotic origin with limited protein-coding capacity. The import of nuclear-encoded proteins and nucleic acids is required and essential for maintaining organelle mass, number, and activity. As plant mitochondria do not encode all the necessary tRNA types required, the import of cytosolic tRNA is vital for organelle maintenance. Recently, two mitochondrial outer membrane proteins, named Tric1 and Tric2, for tRNA import component, were shown to be involved in the import of cytosolic tRNA. Tric1/2 binds tRNA(ala)via conserved residues in the C-terminal Sterile Alpha Motif (SAM) domain. Here we report the X-ray crystal structure of the Tric1 SAM domain. We identified the ability of the SAM domain to form a helical superstructure with six monomers per helical turn and key amino acid residues responsible for its formation. We determined that the oligomerization of the Tric1 SAM domain may play a role in protein function whereby mutation of Gly241 introducing a larger side chain at this position disrupted the oligomer and resulted in the loss of RNA binding capability. Furthermore, complementation of Arabidopsis thaliana Tric1/2 knockout lines with a mutated Tric1 failed to restore the defective plant phenotype. AlphaFold2 structure prediction of both the SAM domain and Tric1 support a cyclic pentameric or hexameric structure. In the case of a hexameric structure, a pore of sufficient dimensions to transfer tRNA across the mitochondrial membrane is observed. Our results highlight the importance of oligomerization of Tric1 for protein function.

Structural analysis of the SAM domain of the Arabidopsis mitochondrial tRNA import receptor.,Olasz B, Smithers L, Evans GL, Anandan A, Murcha MW, Vrielink A J Biol Chem. 2024 Apr 4;300(5):107258. doi: 10.1016/j.jbc.2024.107258. PMID:38582448<ref>PMID:38582448</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8ucy" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Arabidopsis thaliana]]
[[Category: Large Structures]]
[[Category: Evans GL]]
[[Category: Olasz B]]
[[Category: Vrielink A]]