Abstract: Roscovitine, a specific inhibitor of M-phase promoting factor kinase activity was used to inhibit the completion of meiotic maturation of bovine oocytes. The objectives of this study were to evaluate the nuclear maturation of bovine oocytes pre-cultured with various concentrations (0, 50, 100 and 200 μM) of roscovitine before in vitro Maturation (IVM) and to examine the development of Somatic Cell Nuclear Transfer (SCNT) embryos derived from the oocytes pre-cultured with roscovitine. Before IVM, 72% of oocytes that were cultured without roscovitine (control) had reached the Metaphase II (MII) stage whereas culture with roscovitine decreased the rates of oocytes reaching MII (11-27%). After IVM, the maturation rate of oocytes pre-cultured with 200 μM roscovitine was significantly higher than that of control oocytes (79 vs. 58%). Moreover, significantly more oocytes extruded the first polar body in the 50 μM roscovitine group than in the control group (64 vs. 51%). The rate of blastocyst formation of reconstructed embryos derived from oocytes pre-cultured with 50 μM roscovitine was significantly higher than that from the control oocytes (14 vs. 6%). In this study, the addition of roscovitine to culture medium delays the completion of meiotic maturation of bovine oocytes and the cytoplasm derived from oocytes pre-cultured under meiotic inhibition can support the development of SCNT embryos.
Yukine Kaedei, Akira Fujiwara, Aya Ito, Fuminori Tanihara, Yasuhiro Morita, Keisuke Hanatate, Vien Luu Viet, Zhao Namula and Takeshige Otoi, 2010. Effect of Roscovitine Pretreatment on the Meiotic Maturation of Bovine Oocytes and their Subsequent Development after Somatic Cell Nuclear Transfer. Journal of Animal and Veterinary Advances, 9: 2848-2853.