Sexual dimorphic expression of DMRT1 and Sox9a during gonadal differentiation and hormone-induced sex reversal in the teleost fish Nile tilapia (Oreochromis niloticus).
We examined the expression profiles of tDMRT1 and Sox9a during gonadal sex differentiation and hormone-induced sex reversal. tDMRT1 was detected in the gonial germ-cell-surrounding cells in XY fry specifically before the appearance of any signs of morphological sex differentiation, that is, sex differences in germ cell number and histogenesis, such as differentiation into intratesticular efferent duct or ovarian cavity. The signals became localized in the Sertoli and epithelial cells comprising the efferent duct during gonadal differentiation. After the induction of XY sex reversal with estrogen, tDMRT1 decreased and then disappeared completely. In contrast, tDMRT1 was expressed in the germ-cell-surrounding cells in XX sex reversal with androgen. On the other hand, Sox9a did not show sexual dimorphism before the appearance of sex differences in histogenesis and was not expressed in the efferent duct in the testis. These results suggest that tDMRT1 is a superior testicular differentiation marker in tilapia.
Kobayashi
Tohru
T
Department of Developmental Biology, National Institute for Basic Biology, Okazaki, Japan. tuhrukob@affrc.go.jp
Kajiura-Kobayashi
Hiroko
H
Guan
Guijun
G
Nagahama
Yoshitaka
Y
D000728:Androgens / Q000494:pharmacology; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D023681:Cichlids / Q000235:genetics* / Q000254:growth & development; D012734:Disorders of Sex Development; D005260:Female; D029941:Fish Proteins / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D006066:Gonads / Q000254:growth & development / Q000378:metabolism*; D006609:High Mobility Group Proteins / Q000235:genetics; D006728:Hormones / Q000494:pharmacology*; D017403:In Situ Hybridization; D008297:Male; D010053:Ovary / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055758:SOX9 Transcription Factor; D012733:Sex Differentiation / Q000187:drug effects / Q000235:genetics; D013737:Testis / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics
D000728:Androgens; C110547:DMRT1 protein; D029941:Fish Proteins; D006609:High Mobility Group Proteins; D006728:Hormones; D055758:SOX9 Transcription Factor; D014157:Transcription Factors