Expression of non-muscle tropomyosin (TPM3) in porcine oocytes during maturation
Keywords:Non-muscle tropomyosin, expression, porcine oocytes.
Tropomyosins are actin-binding proteins that play an important role in regulating the function of actin filaments in both muscle and non-muscle cells. Non-muscle tropomyosin (TPM3) is crucial for asymmetric cell division and maintenance of cortical integrity of murine oocytes. However, expression and function of TPM3 in porcine oocytes are unknown. In this study we investigated dynamic localization and expression level of TPM3 in porcine oocytes during meiotic maturation. Porcine oocytes collected from the ovaries of pre-pubertal gilts were incubated in TCM 199 maturation medium at 38.5°C in a humidified atmosphere of 5% CO2. Denuded oocytes at different meiotic stages (germinal vesicle (GV), germinal vesicle breakdown (GVBD), metaphase I (MI), and metaphase II (MII)) were used for determining localization of TPM3 using immunostaining and expression level of TPM3 mRNA using quantitative PCR. Results showed that TPM3 protein was located at the membrane of oocytes in all four stages of maturation and the amounts of TPM3 mRNA were similar (p > 0.05) regardless of the stages. The further studies should be concentrated on the role of TPM3 in porcine oocytes.