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4qqf

From Proteopedia

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Crystal structure of mitochondrial import inner membrane translocase subunit TIM50

Structural highlights

4qqf is a 6 chain structure with sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.672Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

TIM50_YEAST Essential component of the TIM23 complex, a complex that mediates the translocation of transit peptide-containing proteins across the mitochondrial inner membrane. Required to direct preproteins in transit and direct them to the channel protein TIM23, and possibly facilitates transfer of the translocating proteins from the TOM complex to the TIM23 complex. Does not act as a structural subunit of the TIM23 complex but plays a dynamic role in protein import. Has no phosphatase activity.^[1] ^[2] ^[3]

Publication Abstract from PubMed

Mitochondrial preproteins are transported through the translocase of the outer membrane (TOM) complex. Tim50 and Tim23 then transfer preproteins with N-terminal targeting presequences through the intermembrane space (IMS) across the inner membrane. The crystal structure of the IMS domain of Tim50 [Tim50(164-361)] has previously been determined to 1.83 A resolution. Here, the crystal structure of Tim50(164-361) at 2.67 A resolution that was crystallized using a different condition is reported. Compared with the previously determined Tim50(164-361) structure, significant conformational changes occur within the protruding beta-hairpin of Tim50 and the nearby helix A2. These findings indicate that the IMS domain of Tim50 exhibits significant structural plasticity within the putative presequence-binding groove, which may play important roles in the function of Tim50 as a receptor protein in the TIM complex that interacts with the presequence and multiple other proteins. More interestingly, the crystal packing indicates that helix A1 from the neighboring monomer docks into the putative presequence-binding groove of Tim50(164-361), which may mimic the scenario of Tim50 and the presequence complex. Tim50 may recognize and bind the presequence helix by utilizing the inner side of the protruding beta-hairpin through hydrophobic interactions. Therefore, the protruding beta-hairpin of Tim50 may play critical roles in receiving the presequence and recruiting Tim23 for subsequent protein translocations.

The structure of Tim50(164-361) suggests the mechanism by which Tim50 receives mitochondrial presequences.,Li J, Sha B Acta Crystallogr F Struct Biol Commun. 2015 Sep;71(Pt 9):1146-51. doi:, 10.1107/S2053230X15013102. Epub 2015 Aug 25. PMID:26323300^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Geissler A, Chacinska A, Truscott KN, Wiedemann N, Brandner K, Sickmann A, Meyer HE, Meisinger C, Pfanner N, Rehling P. The mitochondrial presequence translocase: an essential role of Tim50 in directing preproteins to the import channel. Cell. 2002 Nov 15;111(4):507-18. PMID:12437924
↑ Yamamoto H, Esaki M, Kanamori T, Tamura Y, Nishikawa Si, Endo T. Tim50 is a subunit of the TIM23 complex that links protein translocation across the outer and inner mitochondrial membranes. Cell. 2002 Nov 15;111(4):519-28. PMID:12437925
↑ Chacinska A, Rehling P, Guiard B, Frazier AE, Schulze-Specking A, Pfanner N, Voos W, Meisinger C. Mitochondrial translocation contact sites: separation of dynamic and stabilizing elements in formation of a TOM-TIM-preprotein supercomplex. EMBO J. 2003 Oct 15;22(20):5370-81. PMID:14532110 doi:http://dx.doi.org/10.1093/emboj/cdg532
↑ Li J, Sha B. The structure of Tim50(164-361) suggests the mechanism by which Tim50 receives mitochondrial presequences. Acta Crystallogr F Struct Biol Commun. 2015 Sep;71(Pt 9):1146-51. doi:, 10.1107/S2053230X15013102. Epub 2015 Aug 25. PMID:26323300 doi:http://dx.doi.org/10.1107/S2053230X15013102

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4qqf"

Categories: Large Structures | Saccharomyces cerevisiae | Li JZ

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[4qqf]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4QQF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4QQF FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.672&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=4qqf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4qqf OCA], [https://pdbe.org/4qqf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4qqf RCSB], [https://www.ebi.ac.uk/pdbsum/4qqf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4qqf ProSAT]</span></td></tr>
 </table>

4qqf

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Current revision

Crystal structure of mitochondrial import inner membrane translocase subunit TIM50

Structural highlights

Function

Publication Abstract from PubMed

References

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