Selective egg cell polyspermy bypasses the triploid block
نویسندگان
چکیده
منابع مشابه
Egg cortical granule N-acetylglucosaminidase is required for the mouse zona block to polyspermy
The mammalian egg must be fertilized by only one sperm to prevent polyploidy. In most mammals studied to date, the primary block to polyspermy occurs at the zona pellucida, the mammalian egg coat, after exocytosis of the contents of the cortical granules into the perivitelline space. The exudate acts on the zona, causing it to lose its ability to bind sperm and to be penetrated by sperm previou...
متن کاملSperm competition and female avoidance of polyspermy mediated by sperm-egg biochemistry
Nearly simultaneous fertilization of an egg by two or more sperm (polyspermy) is a lethal condition in most organisms. Sperm competing for an egg face opposing selective pressures. The race to fertilize favours rapid penetration of the egg’s outer protective layer; a close finish between two sperm leads to polyspermy and death. Under most conditions of sperm competition, selection favours maxim...
متن کاملDefending the zygote: search for the ancestral animal block to polyspermy.
Fertilization is the union of a single sperm and an egg, an event that results in a diploid embryo. Animals use many mechanisms to achieve this ratio; the most prevalent involves physically blocking the fusion of subsequent sperm. Selective pressures to maintain monospermy have resulted in an elaboration of diverse egg and sperm structures. The processes employed for monospermy are as diverse a...
متن کاملStudies of the mechanism of the electrical polyspermy block using voltage clamp during cross-species fertilization
Prevention of polyspermic fertilization in sea urchins (Jaffe, 1976, Nature (Lond.). 261:68-71) and the worm Urechis (Gould-Somero, Jaffe, and Holland, 1979, J. Cell Biol. 82:426-440) involves an electrically mediated fast block. The fertilizing sperm causes a positive shift in the egg's membrane potential; this fertilization potential prevents additional sperm entries. Since in Urechis the egg...
متن کاملEstablishment of the mammalian membrane block to polyspermy: evidence for calcium-dependent and -independent regulation.
One crucial result of egg activation is the establishment of blocks on the zona pellucida and the egg plasma membrane to prevent fertilization by additional sperm. The mechanism(s) by which a mammalian egg regulates the establishment of the membrane block to polyspermy is largely unknown. Since Ca(2+) signaling regulates several egg activation events, this study investigates how sperm-induced C...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: eLife
سال: 2020
ISSN: 2050-084X
DOI: 10.7554/elife.52976