Protein insertase that mediates insertion of transmembrane proteins into the mitochondrial outer membrane. Catalyzes insertion of proteins with alpha-helical transmembrane regions, such as signal-anchored, tail-anchored and multi-pass membrane proteins. Does not mediate insertion of beta-barrel transmembrane proteins (By similarity). Also acts as a receptor for the truncated form of pro-apoptotic BH3-interacting domain death agonist (p15 BID) and has therefore a critical function in apoptosis. Regulates the quiescence/cycling of hematopoietic stem cells (HSCs). Acts as a regulator of mitochondrial fusion, essential for the naive-to-primed interconversion of embryonic stem cells (ESCs). Acts as a regulator of lipid homeostasis and has a regulatory role in adipocyte differentiation and biology (By similarity).
Subcellular locations: Mitochondrion outer membrane