Group X phospholipase A2 is released during sperm acrosome reaction and controls fertility outcome in mice.
- Others:
- Grenoble Institut des Neurosciences (GIN) ; Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Santé et de la Recherche Médicale (INSERM)
- Institut de pharmacologie moléculaire et cellulaire (IPMC) ; Université Nice Sophia Antipolis (1965 - 2019) (UNS) ; COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)
- Biomembrane Signaling Project ; Tokyo Metropolitan Institute of Medical Science (TMIMS)
- Department of Health Chemistry, School of Pharmaceutical Sciences ; University Showa
- PRESTO [JST ; Japan Science and Technology Agency
- Région Rhône-Alpes; CNRS; INSERM; Association pour la Recherche sur le cancer (grant 3977); Agence Nationale de la Recherche; Ministry of Education, Science, Culture, Sports and Technology of Japan; PRESTO program of the Japan Science and Technology Agency; NOVARTIS Foundation for the Promotion of Science; the Toray Science Foundation; Région Rhône-Alpes fellowship
Citation
Description
Ejaculated mammalian sperm must undergo a maturation process called capacitation before they are able to fertilize an egg. Several studies have suggested a role for members of the secreted phospholipase A2 (sPLA2) family in capacitation, acrosome reaction (AR), and fertilization, but the molecular nature of these enzymes and their specific roles have remained elusive. Here, we have demonstrated that mouse group X sPLA2 (mGX) is the major enzyme present in the acrosome of spermatozoa and that it is released in an active form during capacitation through spontaneous AR. mGX-deficient male mice produced smaller litters than wild-type male siblings when crossed with mGX-deficient females. Further analysis revealed that spermatozoa from mGX-deficient mice exhibited lower rates of spontaneous AR and that this was associated with decreased in vitro fertilization (IVF) efficiency due to a drop in the fertilization potential of the sperm and an increased rate of aborted embryos. Treatment of sperm with sPLA2 inhibitors and antibodies specific for mGX blocked spontaneous AR of wild-type sperm and reduced IVF success. Addition of lysophosphatidylcholine, a catalytic product of mGX, overcame these deficiencies. Finally, recombinant mGX triggered AR and improved IVF outcome. Taken together, our results highlight a paracrine role for mGX during capacitation in which the enzyme primes sperm for efficient fertilization and boosts premature AR of a likely phospholipid-damaged sperm subpopulation to eliminate suboptimal sperm from the pool available for fertilization.
Abstract
International audience
Additional details
- URL
- https://hal.archives-ouvertes.fr/hal-00497561
- URN
- urn:oai:HAL:hal-00497561v1
- Origin repository
- UNICA