Fare oosit maturasyonunda C-ABL tirozin kinaz ve memeli rapamisin hedefi (MTOR) düzenlenmesinin belirlenmesi

In this thesis, we aimed to investigate the roles of mTOR and c-Abl and the relationship between them during the process of oocyte maturation which includes Prophase I (PI), Metaphase I (MI), and Metaphase II (MII) stages of oocyte development. We collected GV oocytes from mouse ovaries and then treated them with imatinib (1 µM, 5 µM and 10 µM) which is a c-Abl inhibitor and rapamycin (1000 µM) which is an mTORC1 inhibitor for 16 hr. We then evaluated the developmental potential of GV oocytes to MII stage. We recorded the rate of GV, MI and MII oocytes after the culture period and scored them. We also evaluated mRNA levels of mTOR and c-Abl with qRT-PCR in GV, MI and MII oocyte stages in all experimental groups. According to our findings, Rapamycin had a slightly positive effect on the rate of oocyte maturation while it had a slightly negative effect on the oocyte morphology. On the contrary (Interestingly), the mRNA expression of mTOR in GV, MI and MII oocytes in the rapamycin group did not decrease. Imatinib had a negative effect on both oocyte maturation and morphology in a dose-dependent manner. While 1 μM imatinib had a slightly negative effect, 10 μM imatinib had a greater negative effect on the rate of oocyte maturation and morphology. mRNA expression levels of c-Abl in GV and MII significantly decreased in 1 μM and 5 μM imatinib treatment groups. The qRT-PCR results that compared the mRNA expression levels of c-Abl and mTOR in the GV, MI and MII oocytes in all experimental groups showed that c-Abl inhibition led to an increase in mTOR expression. In this thesis, we suggest that mTOR and c-Abl may have important roles in oocyte maturation. Moreover, we have shown that c-Abl inhibition leads to an increase in mTOR activity. In conclusion, understanding the roles of c-Abl and mTOR during oocyte maturation will help us improve oocyte and embryo quality and also will provide new insights into mechanisms underlying the regulation of oocyte maturation. Key words: c-Abl, mTOR, oocyte maturation, mouse.