Sperm-induced Ca2+ release in mammalian eggs: The roles of PLCζ, InsP3, and ATP

Swann, Karl ORCID: https://orcid.org/0000-0002-4355-1449 2023. Sperm-induced Ca2+ release in mammalian eggs: The roles of PLCζ, InsP3, and ATP. Cells 12 (24) , 2809. 10.3390/cells12242809

Preview

PDF - Published Version Available under License Creative Commons Attribution. Download (1MB) | Preview

Abstract

Mammalian egg activation at fertilization is triggered by a long-lasting series of increases in cytosolic Ca2+ concentration. These Ca2+ oscillations are due to the production of InsP3 within the egg and the subsequent release of Ca2+ from the endoplasmic reticulum into the cytosol. The generation of InsP3 is initiated by the diffusion of sperm-specific phospholipase Czeta1 (PLCζ) into the egg after gamete fusion. PLCζ enables a positive feedback loop of InsP3 production and Ca2+ release which then stimulates further InsP3 production. Most cytosolic Ca2+ increases in eggs at fertilization involve a fast Ca2+ wave; however, due to the limited diffusion of InsP3, this means that InsP3 must be generated from an intracellular source rather than at the plasma membrane. All mammalian eggs studied generated Ca2+ oscillations in response to PLCζ, but the sensitivity of eggs to PLCζ and to some other stimuli varies between species. This is illustrated by the finding that incubation in Sr2+ medium stimulates Ca2+ oscillations in mouse and rat eggs but not eggs from other mammalian species. This difference appears to be due to the sensitivity of the type 1 InsP3 receptor (IP3R1). I suggest that ATP production from mitochondria modulates the sensitivity of the IP3R1 in a manner that could account for the differential sensitivity of eggs to stimuli that generate Ca2+ oscillations.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Biosciences
Publisher:	MDPI
ISSN:	2073-4409
Date of First Compliant Deposit:	5 January 2024
Date of Acceptance:	6 December 2023
Last Modified:	11 Jan 2024 12:15
URI:	https://orca.cardiff.ac.uk/id/eprint/165296

Actions (repository staff only)

Edit Item