PLCζ or PAWP: revisiting the putative mammalian sperm factor that triggers egg activation and embryogenesis.
In mammals, egg activation is initiated by multiple cytosolic Ca(2+) transients (Ca(2+) oscillations) that are triggered following delivery of a putative sperm factor from the fertilizing sperm. The identity of this 'sperm factor' thus holds much significance, not only as a vital component in creating a new life, but also for its potential therapeutic and diagnostic value in human infertility. Recent data have emerged suggesting the sperm factor may be a post-acrosomal sheath WW domain-binding protein (PAWP). However, a significant body of research points to a testis-specific phospholipase C zeta (PLCζ) as the sperm factor. Herein, we examine the evidence presented in favour of PAWP in relation to PLCζ and the requisite physiological properties of the mammalian sperm factor.
Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK College of Medicine, Alfaisal University, Riyadh, Kingdom of Saudi Arabia Department of Comparative Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia.
Junaid
J
Kashir
Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK.
Michail
M
Nomikos
Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK.
Karl
K
Swann
Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK lait@cardiff.ac.uk.
F Anthony
FA
Lai
D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D047108:Embryonic Development; D005260:Female; D005306:Fertilization; D006801:Humans; D008297:Male; D008954:Models, Biological; D054801:Phosphoinositide Phospholipase C / Q000378:metabolism*; D029589:Seminal Plasma Proteins / Q000378:metabolism*; D015398:Signal Transduction; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000201:enzymology / Q000378:metabolism
D002352:Carrier Proteins; D029589:Seminal Plasma Proteins; C519840:WBP2NL protein, human; C499235:PLCZ1 protein, human; D054801:Phosphoinositide Phospholipase C
PAWP; PLC-zeta; egg activation; fertilization; sperm factor