Download MendeleyStructural insights into the pro-apoptotic function of mitochondrial serine protease HtrA2/Omi.
Li, W., Srinivasula, S.M., Chai, J., Li, P., Wu, J.W., Zhang, Z., Alnemri, E.S., Shi, Y.(2002) Nat Struct Biol 9: 436-441
- PubMed: 11967569
- DOI: https://doi.org/10.1038/nsb795
- Primary Citation of Related Structures:
1LCY - PubMed Abstract:
HtrA2/Omi, a mitochondrial serine protease in mammals, is important in programmed cell death. However, the underlining mechanism of HtrA2/Omi-mediated apoptosis remains unclear. Analogous to the bacterial homolog HtrA (DegP), the mature HtrA2 protein contains a central serine protease domain and a C-terminal PDZ domain. The 2.0 A crystal structure of HtrA2/Omi reveals the formation of a pyramid-shaped homotrimer mediated exclusively by the serine protease domains. The peptide-binding pocket of the PDZ domain is buried in the intimate interface between the PDZ and the protease domains. Mutational analysis reveals that the monomeric HtrA2/Omi mutants are unable to induce cell death and are deficient in protease activity. The PDZ domain modulates HtrA2/Omi-mediated cell death activity by regulating its serine protease activity. These structural and biochemical observations provide an important framework for deciphering the mechanisms of HtrA2/Omi-mediated apoptosis.
Organizational Affiliation:
Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, New Jersey 08544, USA.
