Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 1 de 1
Filtrar
Más filtros

Bases de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Biol Reprod ; 74(5): 857-64, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16421234

RESUMEN

To elucidate the involvement of aromatase in sex reversal, the gilthead seabream ovarian P450 aromatase (cyp19a1a) cDNA and its 5'-flanking region were isolated and characterized. Northern blot analysis revealed that only one cyp19a1a transcript (2.0 kb) is expressed in the ovary. Four cAMP-responsive elements were identified at the 5'-flanking region of seabream cyp19a1a indicating a high potential to respond to gonadotropin signaling. Studying the seasonal profile, two expression peaks of cyp19a1a transcripts in the ovarian tissues were found in July (about 15000 copies/ng total RNA) for ambisexual fish and in December (about 12000 copies/ng total RNA) for spawning females. Starting from September, transcript levels of cyp19a1a in the ovarian portions of the male-developing gonads gradually decreased. Furthermore, the ovarian portions of the female gonads expressed cyp19a1a at a significantly higher level than the ovarian portions of the male gonads after November. Taken together with levels of plasma estradiol in reversing females being significantly higher than those in developing males, the above results reinforce the importance of cyp19a1a in sex reversal. In vitro exposure of ovarian fragments to gonadotropins (hCG) at 1, 10, and 100 IU/ml significantly (P < 0.05) upregulated cyp19a1a expression. Additionally, expression of cyp19a1a displayed a stronger and significant correlation with the transcript expression of ovarian Lh receptor rather than Fsh receptor during the ambisexual stage. Our results indicate that the differential expression of cyp19a1a gene is associated with sex reversal and that gonadotropin signals (particularly Lh) may serve as major players in regulating the expression of cyp19a1a during the process of sex reversal.


Asunto(s)
Aromatasa/fisiología , Organismos Hermafroditas , Dorada/fisiología , Procesos de Determinación del Sexo , Región de Flanqueo 5' , Animales , Aromatasa/genética , Aromatasa/metabolismo , Northern Blotting , ADN Complementario , Estradiol/sangre , Femenino , Hormonas Gonadales/genética , Hormonas Gonadales/metabolismo , Hormonas Gonadales/fisiología , Gonadotropinas/fisiología , Gónadas/crecimiento & desarrollo , Masculino , Reacción en Cadena de la Polimerasa/métodos , Estaciones del Año , Análisis de Secuencia de ADN
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA