PT - JOURNAL ARTICLE AU - Aujan Mehregan AU - Goli Ardestani AU - Ingrid Carvacho AU - Rafael Fissore TI - Simultaneous Deletion of Transient Receptor Potential Vanilloid 3 and Cacna1h Undermines CA<sup>2+</sup> Homeostasis in Oocytes and Fertility in Mice AID - 10.1101/443622 DP - 2018 Jan 01 TA - bioRxiv PG - 443622 4099 - http://biorxiv.org/content/early/2018/10/15/443622.short 4100 - http://biorxiv.org/content/early/2018/10/15/443622.full AB - In mammals, calcium (Ca2+) influx fills the endoplasmic reticulum, from where Ca2+ is released following fertilization to induce egg activation. However, an incomplete index of the plasma membrane channels and their specific contributions that underlie this influx in oocytes and eggs led us to simultaneously knock out the transient receptor potential vanilloid, member 3 (TRPV3) channel and the T-type channel, CaV3.2. Double knockout (dKO) females displayed subfertility and their oocytes and eggs showed significantly diminished Ca2+ store content and oscillations after fertilization compared to controls. We also found that the cell cycle stage during maturation determines the functional expression of channels whereby they show a distinct permeability to certain ions. In total, we demonstrate that TRPV3 and CaV3.2 are required for initiating physiological oscillations and that Ca2+ influx dictates the periodicity of oscillations during fertilization. dKO gametes will be indispensable to identify the complete native channel currents present in mammalian eggs.