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Capture and functional conversion of mitochondrial protein translocase by lipid metabolism enzyme (Mim2 SILAC IPs)

ABSTRACT: Mitochondria play central roles in energetics and metabolism of eukaryotic cells. Their outer membrane is essential for protein transport, membrane dynamics, signalling and metabolic exchange with other cellular compartments. The mitochondrial import complex MIM functions as main translocase for importing the precursors of more than 90% of integral outer membrane proteins. Here we report that the MIM complex performs a second major function in lipid droplet homeostasis. Lipid droplets are crucial in cellular lipid metabolism and as storage organelles for neutral lipids. The lipid metabolism enzyme Ayr1 captures the MIM complex, promoting the formation of mitochondria-lipid droplet contact sites. MIM and Ayr1 enhance the lipid droplet number in cells. Ayr1 binds to MIM via its single hydrophobic segment in a substrate-mimicry mechanisms but remains bound and is not released into the outer membrane. The functional diversity is mediated by different MIM complexes: MIM-Ayr1 for recruiting lipid droplets and MIM-preprotein for protein insertion into the outer membrane. Our work uncovers translocase capture as mechanism for functional conversion of a membrane protein complex from protein insertion to lipid metabolism.

INSTRUMENT(S):

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: Julian Bender

LAB HEAD: Bettina Warscheid

PROVIDER: PXD062106 | Pride | 2026-01-21

REPOSITORIES: Pride

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	ORBI-RSLC013874.raw	Raw
	ORBI-RSLC013878.raw	Raw
	ORBI-RSLC013882.raw	Raw

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