[5][6][7] The protein was identified in the laboratory of Xiaodong Wang as an activator of caspase-3 in the presence of cytochromeC and dATP.
[8] This gene encodes a cytoplasmic protein that forms one of the central hubs in the apoptosis regulatory network.
The apoptosome binds and cleaves Procaspase-9 protein, releasing its mature, activated form.
The precise mechanism for this reaction is still debated though work published by Guy Salvesen suggests that the apoptosome may induce caspase-9 dimerization and subsequent autocatalysis.
[citation needed] Alternative splicing results in several transcript variants encoding different isoforms.