EXPRESSION ANALYSIS OF THE NILE TILAPIA FERTILITY GENES AND IMPROVEMENT OF MEDAKA STEM CELL CULTURE

Abstract

THE GENES BOULE, DAZL AND DAZ-LIKE WHICH ARE MEMBERS OF DAZ FAMILY SHOW VARIED EXPRESSION PATTERN DURING GAMETOGENESIS. FIRSTLY, MOLECULAR CLONING AND SEQUENCE ANALYSIS IDENTIFIED TILAPIA BOULE AND DAZL CDNA. AN RT-PCR ANALYSIS REVEALED BISEXUAL GONAD-SPECIFIC EXPRESSION. CHROMOGENIC AND FLUORESCENT IN SITU HYBRIDIZATION ANALYSES REVEALED GERM CELL-SPECIFIC EXPRESSION. IN THE OVARY, BOULE AND DAZL RNA WERE EXPRESSED FROM OOGONIA TO PRE-VITOLLOGENIC OOCYTES AND DECREASED IN OOCYTES AS VITELLOGENESIS PROGRESSED, BUT STAGE-SPECIFIC PEAK EXPRESSION WAS OBSERVED. IN THE TESTIS, BOULE AND DAZL RNA EXISTED THROUGHOUT SPERMATOGENESIS EXCEPT BOULE IN SPERM. THE DATA DEMONSTRATE THAT BOULE, DAZL ARE GERM CELL MARKERS IN TILAPIA AND BISEXUAL, STAGE-SPECIFIC GERMLINE EXPRESSION OF THESE GENES ARE CONSERVED IN DIVERSE TELEOST FISH SPECIES. SECONDLY, ROCK INHIBITOR Y-27632 (ROCK INHIBITOR) WAS UTILIZED TO REDUCE CRYOPRESERVATION-INDUCED APOPTOSIS IN MEDAKA HAPLOID ES (HES) CELLS. Y-27632 SIGNIFICA