Sperm-specific post-acrosomal WW-domain binding protein (PAWP) does not cause Ca2+ release in mouse oocytes.
نویسندگان
چکیده
Mature mammalian oocytes undergo a prolonged series of cytoplasmic calcium (Ca(2+)) oscillations at fertilization that are the cause of oocyte activation. The Ca(2+) oscillations in mammalian oocytes are driven via inositol 1,4,5-trisphosphate (IP3) generation. Microinjection of the sperm-derived phospholipase C-zeta (PLCζ), which generates IP3, causes the same pattern of Ca(2+) oscillations as observed at mammalian fertilization and it is thought to be the physiological agent that triggers oocyte activation. However, another sperm-specific protein, 'post-acrosomal WW-domain binding protein' (PAWP), has also been reported to elicit activation when injected into mammalian oocytes, and to produce a Ca(2+) increase in frog oocytes. Here we have investigated whether PAWP can induce fertilization-like Ca(2+) oscillations in mouse oocytes. Recombinant mouse PAWP protein was found to be unable to hydrolyse phosphatidylinositol 4,5-bisphosphate in vitro and did not cause any detectable Ca(2+) release when microinjected into mouse oocytes. Microinjection with cRNA encoding either the untagged PAWP, or yellow fluorescent protein (YFP)-PAWP, or luciferase-PAWP fusion proteins all failed to trigger Ca(2+) increases in mouse oocytes. The lack of response in mouse oocytes was despite PAWP being robustly expressed at similar or higher concentrations than PLCζ, which successfully initiated Ca(2+) oscillations in every parallel control experiment. These data suggest that sperm-derived PAWP is not involved in triggering Ca(2+) oscillations at fertilization in mammalian oocytes.
منابع مشابه
Functional disparity between human PAWP and PLCζ in the generation of Ca2+ oscillations for oocyte activation.
Mammalian oocyte activation is mediated by cytosolic calcium (Ca(2+)) oscillations initiated upon delivery of a putative 'sperm factor' by the fertilizing sperm. Previous studies suggest the identity of this sperm factor as the testis-specific phospholipase C-zeta (PLCζ). Recently, a post-acrosomal sheath WW domain-binding protein (PAWP) has been proposed as an alternative sperm factor candidat...
متن کاملIs PAWP the “real” sperm factor?
Mammalian embryo development is initiated by intracellular Ca2+ oscillations that result in oocyte activation following gamete membrane fusion. It is widely believed that oocyte Ca2+ oscillations are triggered by a sperm-specific protein, phospholipase C-zeta (PLCζ) that activates InsP3 production leading to repetitive Ca2+ release from intracellular stores. However, a recent report in the FASE...
متن کاملRe: Is PAWP the ‘real’ sperm factor?
Mammalian embryo development is init iated by intracel lular Ca2+ oscillations that result in oocyte activation following gamete membrane fusion. It is widely believed that oocyte Ca2+ oscillations are triggered by a sperm-specific protein, phospholipase C-zeta (PLCζ) that activates InsP3 production leading to repetitive Ca2+ release from intracellular stores. However, a recent report in the FA...
متن کاملRelationship between Expression of Sperm PAWP Protein with Fertilization Rate in Infertile Men Candidate for ICSI Technique
Backgroundm: Post-acrosomal sheath WW domain binding protein (PAWP) is one of the proteins that is expressed during spermatogenesis process and has several roles in sperm differentiation, fertilization, and early embryonic development. The aim of this study was assessment of the relationship between PAWP expression with fertilization rate in infertile men candidate for intracytoplasmic sperm...
متن کاملContribution of a Sperm Protein, Pawp, to the Signal Transduct Pathway during Vertebrate Fertilization
PAWP, postacrosomal sheath WW domain binding protein, is a novel sperm protein identified as a candidate sperm borne, oocyte-activating factor (SOAF). PAWP induces both early and later egg activation events including meiotic resumption, pronuclear formation and egg cleavage. Based on the fact that calcium increase is universally accepted as the sole requirement for egg activation, we hypothesiz...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Molecular human reproduction
دوره 20 10 شماره
صفحات -
تاریخ انتشار 2014