The serine protease Omi/HtrA2 is released from mitochondria during apoptosis. Omi interacts with caspase-inhibitor XIAP and induces enhanced caspase activity
Cell Death and Differentiation (2002) - Comment
pubmed: 11803371  doi: 10.1038/sj.cdd.4400970  issn: 1350-9047  issn: 1476-5403 

G Van Loo, M Van Gurp, B Depuydt, S M Srinivasula, I Rodriguez, E S Alnemri, K Gevaert, J Vandekerckhove, W Declercq, P Vandenabeele