Apop-1 Induces Caspase-Dependent Apoptosis

Apoptosis is a form of genetically programmed cell death, which plays a pivotal role in normal development and the maintenance of homeostasis of a variety of tissues including cardiovascular system. Apop-1 is a soluble protein consisting of 194 amino acids with a mitochondrial localization signal at its N-terminus. RT-PCR data revealed that Apop-1 is expressed in all the organs tested. Immunofluorescence study showed that Apop-1 protein is localized in mitochondria. Transient transfection experiment showed Apop-1 induces apoptosis of cultured VSMC, and this apoptosis is inhibited by a pan-caspase inhibitor Z-VAD. The apoptosis induced by Apop-1 may contribute to the loss of VSMC in atherosclerosis, which will influence the stability of atherosclerotic plaques.