6lo8

Structural highlights

Function

TIM22_YEAST Essential core component of the TIM22 complex, a complex that mediates the import and insertion of multi-pass transmembrane proteins, such as mitochondrial carrier family members, into the mitochondrial inner membrane. In the TIM22 complex, it constitutes the voltage-activated and signal-gated channel. Forms a twin-pore translocase that uses the membrane potential as external driving force in 2 voltage-dependent steps. Mediates the insertion of precursor proteins in a 3 step process. After the precursor is tethered to the translocase without losing energy from the Delta(psi), 2 energy-requiring steps are needed. First, Delta(psi) acts on the precursor protein and promotes its docking in the translocase complex. Then, Delta(psi) and an internal signal peptide together induce rapid gating transitions in one pore and closing of the other pore and drive membrane insertion to completion.^{[1] [2] [3]}

References

1. ↑ Kovermann P, Truscott KN, Guiard B, Rehling P, Sepuri NB, Müller H, Jensen RE, Wagner R, Pfanner N. Tim22, the essential core of the mitochondrial protein insertion complex, forms a voltage-activated and signal-gated channel. Mol Cell. 2002 Feb;9(2):363-73. PMID:11864609 doi:10.1016/s1097-2765(02)00446-x
2. ↑ Rehling P, Model K, Brandner K, Kovermann P, Sickmann A, Meyer HE, Kuhlbrandt W, Wagner R, Truscott KN, Pfanner N. Protein insertion into the mitochondrial inner membrane by a twin-pore translocase. Science. 2003 Mar 14;299(5613):1747-51. PMID:12637749 doi:http://dx.doi.org/10.1126/science.1080945
3. ↑ Sirrenberg C, Bauer MF, Guiard B, Neupert W, Brunner M. Import of carrier proteins into the mitochondrial inner membrane mediated by Tim22. Nature. 1996 Dec 12;384(6609):582-5. PMID:8955274 doi:http://dx.doi.org/10.1038/384582a0