Journal
DEVELOPMENTAL BIOLOGY
Volume 256, Issue 2, Pages 258-275Publisher
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/S0012-1606(02)00134-3
Keywords
meiosis; egg; cyclin B; MPF; embryo
Categories
Ask authors/readers for more resources
Sea urchins are members of a limited group of animals in which meiotic maturation of oocytes is completed prior to fertilization. This is different from oocytes of most animals such as mammals and amphibians in which fertilization reactivates an arrested meiotic cycle. Using a recently developed technique for in vitro maturation of sea urchin oocytes, we analyzed the role of cyclin B, the regulatory component of maturation-promoting factor, in the control of sea urchin oocyte meiotic induction and progression. Oocytes of the sea urchin Lytechinus variegatus accumulate significant amounts of cyclin B mRNA and protein during oogenesis. We analyzed cyclin B synthetic requirements in oocytes and early embryos by inhibiting cyclin B synthesis with DNA and morpholino antisense oligonucleotides. Cyclin B synthesis is not necessary for the entry of G2-arrested oocytes into meiosis; however, it is required for the proper progression through meiotic divisions. Surprisingly, mature sea urchin eggs contain significant cyclin B protein following meiosis that serves as a maternal store for early cleavage divisions. We also find that cyclin A can functionally substitute for cyclin B in early embryos but not in oocytes. These studies provide a foundation for understanding the mechanism of meiotic maturation independent of the zygotic cell cycle. (C) 2003 Elsevier Science (USA). All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available