EXPRESSION OF GLYCINE CLEAVAGE SYSTEM AND EFFECT OF GLYCINE ON IN-VITRO MATURATION, FERTILIZATION AND EARLY EMBRYONIC-DEVELOPMENT IN PIGS

Glycine is the amino acid with the highest concentration in sow oviduc t fluid, uterine fluid and follicular fluid. In this study, the effect of glycine on in vitro maturation, fertilization and early embryonic development in pigs was evaluated. In addition, the expression of T-pr otein, a component of the glycine cleavage enzyme system, was studied in the oocytes, cumulus cells, granulosa cells and oviductal epithelia l cells using the methods of reverse transcription-polymerase chain re action (RT-PCR). The results showed that supplementation of porcine oo cytes with glycine during in vitro maturation improved on the developm ent of embryos in vitro. After fertilization, glycine also enhanced em bryo cleavage rate in the presence, but not in the absence, of oviduct al cells. PCR product corresponding to T-protein was found in uncultur ed oocytes, cumulus cells, granulosa cells and oviductal epithelial ce lls. These results indicate that glycine is an important amino acid fo r the in vitro oocyte maturation, fertilization and early embryonic de velopment in pigs.