Mitochondrial Protein 18kDa (MTP18)

MTP18 is a mitochondrial protein and downstream target of the phosphatidylinositol 3-kinase signaling pathway that plays a role in cell viability and mitochondrial dynamics. The deduced 166-amino acid protein was detected as a 18-kD species by immunoblot analysis, consistent with the predicted molecular mass.

MTP18 colocalized with mitochondria by subcellular fractionation and immunoblot analysis, and by confocal microscopy of HeLa cells transfected with MTP18.FACS analysis showed that reduced MTP18 levels led to a reduction in cell proliferation with an increase in the sub-G1 fraction, suggesting an increase in DNA fragmentation and induction of apoptosis, assayed by cytochrome c release.