# A Yeast Mitochondrial Membrane Methyltransferase-like Protein Can Compensate for $oxa1$ Mutations

* Corresponding author
Abstract : Members of the Oxa1p/Alb3/YidC family mediate the insertion of various organelle or bacterial hydrophobic proteins into membranes. They present at least five transmembrane segments (TM) linked by hydrophilic domains located on both sides of the membrane. To examine how Oxa1p structure relates to its function, we have introduced point mutations and large deletions into various domains of the yeast mitochondrial protein. These mutants allowed us to show the importance of the first TM domain as well as a synergistic interaction between the first loop and the C-terminal tail, which both protrude into the matrix. These mutants also led to the isolation of a high copy suppressor, $OMS1$, which encodes a member of the methyltransferase family. Over-expression of $OMS1$ seems to increase the steady-state level of both the mutant and wild-type Oxa1p. We show that Oms1p is a mitochondrial inner membrane protein inserted independently of Oxa1p. Oms1p presents one TM and a N-in C-out topology with the C-terminal domain carrying the methyltransferase-like domain. A conserved motif within this domain is essential for the suppression of $oxa1$ mutations. We discuss the possible role of Oms1p on Oxa1p intermembrane space domain.
Document type :
Journal articles
Domain :

Cited literature [52 references]

https://hal-cea.archives-ouvertes.fr/cea-02470752
Contributor : Bruno Savelli Connect in order to contact the contributor
Submitted on : Friday, February 7, 2020 - 2:59:34 PM
Last modification on : Thursday, July 8, 2021 - 3:52:00 AM
Long-term archiving on: : Friday, May 8, 2020 - 4:38:59 PM

### File

2004_ J Biol Chem_A Yeast Mito...
Publisher files allowed on an open archive

### Citation

Claire Lemaire, Florence Guibet-Grandmougin, Diane Angles, Geneviève Dujardin, Nathalie Bonnefoy. A Yeast Mitochondrial Membrane Methyltransferase-like Protein Can Compensate for $oxa1$ Mutations. Journal of Biological Chemistry, American Society for Biochemistry and Molecular Biology, 2004, 279 (46), pp.47464-47472. ⟨10.1074/jbc.M404861200⟩. ⟨cea-02470752⟩

Record views