Structural highlights
Function
TIM9_HUMAN Mitochondrial intermembrane chaperone that participates in the import and insertion of multi-pass transmembrane proteins into the mitochondrial inner membrane. May also be required for the transfer of beta-barrel precursors from the TOM complex to the sorting and assembly machinery (SAM complex) of the outer membrane. Acts as a chaperone-like protein that protects the hydrophobic precursors from aggregation and guide them through the mitochondrial intermembrane space.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Import of proteins into mitochondria occurs by coordinated actions of preprotein translocases in the outer and inner membranes. Tim9 and Tim10 are translocase components of the intermembrane space, related to deafness-dystonia peptide 1 (DDP1). They coassemble into a hexamer, TIM9.10, which captures and chaperones precursors of inner membrane metabolite carriers as they exit the TOM channel in the outer membrane. The crystal structure of TIM9.10 reveals a previously undescribed alpha-propeller topology in which helical "blades" radiate from a narrow central pore lined with polar residues. The propeller blades are reminiscent of "tentacles" in chaperones Skp and prefoldin. In each TIM9.10 subunit, a signature "twin CX3C" motif forms two intramolecular disulfides. There is no obvious binding pocket for precursors, which we suggest employ the chaperone-like tentacles of TIM9.10 as surrogate lipid contacts. The first reported crystal structure of a mitochondrial translocase assembly provides insights into selectivity and regulation of precursor import.
Crystal structure of the mitochondrial chaperone TIM9.10 reveals a six-bladed alpha-propeller.,Webb CT, Gorman MA, Lazarou M, Ryan MT, Gulbis JM Mol Cell. 2006 Jan 6;21(1):123-33. PMID:16387659[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Muhlenbein N, Hofmann S, Rothbauer U, Bauer MF. Organization and function of the small Tim complexes acting along the import pathway of metabolite carriers into mammalian mitochondria. J Biol Chem. 2004 Apr 2;279(14):13540-6. Epub 2004 Jan 15. PMID:14726512 doi:http://dx.doi.org/10.1074/jbc.M312485200
- ↑ Webb CT, Gorman MA, Lazarou M, Ryan MT, Gulbis JM. Crystal structure of the mitochondrial chaperone TIM9.10 reveals a six-bladed alpha-propeller. Mol Cell. 2006 Jan 6;21(1):123-33. PMID:16387659 doi:10.1016/j.molcel.2005.11.010
