A discrete pathway for the transfer of intermembrane space proteins across the outer membrane of mitochondria.
Bottom Line: We identified a transient interaction between our model substrates and Tom40.Of interest, outer membrane translocation did not directly involve other core components of the TOM complex, including Tom22.Thus MIA-dependent proteins take another route across the outer mitochondrial membrane that involves Tom40 in a form that is different from the canonical TOM complex.
Affiliation: International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland.Show MeSH
Mentions: We next verified the specificity of the interaction between Mix17FLAG and Tom40 using a yeast strain that carried Tom40HA, a tagged version of Tom40. Tom40HA met the control requirements, in which affinity chromatography via anti-hemagglutinin (HA) agarose allowed the efficient and specific purification of other TOM components, such as Tom22, Tom5, and the peripheral receptors Tom70 and Tom20 (Figure 5A). Affinity chromatography from yeast cells via FLAG tag showed that both Tom40 and Tom40HA were able to interact with Mix17FLAG, thus demonstrating that the Mix17-Tom40 interaction is specific (Figure 5B).
Affiliation: International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland.