Summary: | 碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 98 === Sox family has an important HMG (higher mobility group) domain which can bind with the DNA structure and regulate target genes. They were conserved in many species, and with many functions such as sex determination, testis formation, neuronal development, lymphocyte differentiation, sex differentiation and chondrogenesis. Black porgy, Acanthopagrus schlegeli bleeker, a marine protandrous hermaphrodite fish, have a complicated mechanism in sex differentiation and development. Juvenile fish processed male sex-differentiation about 4 month after hatch and developed to a functional male in 1st spawing season. After spawning, testis regressed and ovary grow up, testis developed again until the 2nd pre-spawning season. Nevertheless, about 40% fish change sex(male to female) in 3rd spawning season. In 0+ yr-old fish, sox3 expression had no obvious variation during sex differentiation, sox5 expression decreased during sex differentiation, sox8 expression increased after sex differetiation and sox9 expression had increased during testis development. E2&AI treatment induecd ovary development in 0+-yr-old fish, sox3 expression had an obvious variation during ovary development, sox5 expression seemed to be related to aromatase expression, sox8 expression had the same results with control experiment and sox9 expression had no obvious variation. In the gonadal regression and development experiment, sox3 expression increased with the ovary development. Sox5 expression increased with the gonadal regression. Sox8 expression had no obvious variation. Sox9 maintain high expression in testis and rapidly decreased in the mature-sperm stage. Sox3 expression appeared to be related to ovary development, especially at primary oocyte stage. Sox3 expressed in primary oocyte by in situ hybridization and immunohistochemical stainning, suggested that sox3 is related to primary oocyte development. Sox5 increased at the regressive stage of ganad and decreased at the developing stage of gonad, suggested that sox5 is related to the regression in testis and ovary both. Sox9 remained at high expression during spermatogenesis and decreased at the mature-sperm stage, suggested that sox9 is related to early spermatogenesis. Sox8 had no obvious variation during gonadal development and regression. However sox8 decreased dramatically after testis excision in 2+-yr-old fish, suggested sox8 might be regulated by androgen.
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