Activation of amphibian oocytes by sperm extracts

作者：Bonilla F; Ajmat M T; Sanchez Toranzo G; Zelarayan L; Oterino J; Buehler M I

来源：Zygote, 2008, 16(4): 303-308.

DOI：10.1017/S0967199408004814

• Bufo arenarum
• Oocyte activation
• Sperm extracts

In the fertilization of most animals, egg activation is accompanied by an increase in cytoplasmatic Ca(2+); however, the mechanism through which the fertilizing sperm induce this phenomenon is still controversial. An increase in intracellular free Ca(2+) is required to trigger egg activation events, a process that includes cortical granule exocytosis, resumption and completion of meiosis and DNA replication, and culminates in the first mitotic cleavage. In this work, we investigated the effect of microinjection and incubation of different fractions of homologous sperm extract on the activation of Bufo arenarum oocytes matured in vitro. Two heat treatment-sensitive fractions obtained by chromatography were able to induce oocyte activation. The sperm fraction, which contained a 24 kDa protein, induced 90% activation when it was microinjected into the oocytes. Whilst the sperm fraction, which contained a 36 kDa protein, was able to induce about 70% activation only when it was applied on the oocyte surface.

• 出版日期2008-11