| First Author | Abi Nahed R | Year | 2016 |
| Journal | J Biol Chem | Volume | 291 |
| Issue | 6 | Pages | 3076-89 |
| PubMed ID | 26655718 | Mgi Jnum | J:230928 |
| Mgi Id | MGI:5766559 | Doi | 10.1074/jbc.M115.677799 |
| Citation | Abi Nahed R, et al. (2016) Progesterone-induced Acrosome Exocytosis Requires Sequential Involvement of Calcium-independent Phospholipase A2beta (iPLA2beta) and Group X Secreted Phospholipase A2 (sPLA2). J Biol Chem 291(6):3076-89 |
| abstractText | Phospholipase A2 (PLA2) activity has been shown to be involved in the sperm acrosome reaction (AR), but the molecular identity of PLA2 isoforms has remained elusive. Here, we have tested the role of two intracellular (iPLA2beta and cytosolic PLA2alpha) and one secreted (group X) PLA2s in spontaneous and progesterone (P4)-induced AR by using a set of specific inhibitors and knock-out mice. iPLA2beta is critical for spontaneous AR, whereas both iPLA2beta and group X secreted PLA2 are involved in P4-induced AR. Cytosolic PLA2alpha is dispensable in both types of AR. P4-induced AR spreads over 30 min in the mouse, and kinetic analyses suggest the presence of different sperm subpopulations, using distinct PLA2 pathways to achieve AR. At low P4 concentration (2 mum), sperm undergoing early AR (0-5 min post-P4) rely on iPLA2beta, whereas sperm undergoing late AR (20-30 min post-P4) rely on group X secreted PLA2. Moreover, the role of PLA2s in AR depends on P4 concentration, with the PLA2s being key actors at low physiological P4 concentrations (</=2 mum) but not at higher P4 concentrations ( approximately 10 mum). |
