Dynamic distribution of spindlin in nucleoli, nucleoplasm and spindle from primary oocytes to mature eggs and its critical function for oocyte-to-embryo transition in gibel carp

✍ Scribed by Min Sun; Zhi Li; Jian-Fang Gui

• Publisher: Wiley (John Wiley & Sons)
• Year: 2010
• Tongue: English
• Weight: 703 KB
• Volume: 313A
• Category: Article
• ISSN: 1932-5223
• DOI: 10.1002/jez.618

✦ Synopsis

Abstract

Spindlin (Spin) was thought as a maternal‐effect factor associated with meiotic spindle. Its role for the oocyte‐to‐embryo transition was suggested in mouse, but its direct evidence for the function had been not obtained in other vertebrates. In this study, we used the __Cag__Spin‐specific antibody to investigate __Cag__Spin expression pattern and distribution during oogenesis of gibel carp (Carassius auratus gibelio). First, the oocyte‐specific expression pattern and dynamic distribution was revealed in nucleoli, nucleoplasm, and spindle from primary oocytes to mature eggs by immunofluorescence localization. In primary oocytes and growth stage oocytes, __Cag__Spin accumulates in nucleoli in increasing numbers along with the oocyte growth, and its disassembly occurs in vitellogenic oocytes, which implicates that __Cag__Spin may be a major component of a large number of nucleoli in fish growth oocytes. Then, co‐localization of __Cag__Spin and β‐tubulin was revealed in meiotic spindle of mature egg, indicating that __Cag__Spin is one spindle‐associated factor. Moreover, microinjection of __Cag__Spin‐specific antibody into the fertilized eggs blocked the first cleavage, and found that the __Cag__Spin depletion resulted in spindle assembly disturbance. Thereby, our study provided the first direct evidence for the critical oocyte‐to‐embryo transition function of Spin in vertebrates, and confirmed that Spin is one important maternal‐effect factor that participates in oocyte growth, oocyte maturation, and oocyte‐to‐embryo transition. J. Exp. Zool. 313A:461–473, 2010. © 2010 Wiley‐Liss, Inc.