INVESTIGADORES
SOMOZA Gustavo Manuel
capítulos de libros
Título:
Methods of sex control in fishes and an overview of novel hypotheses concerning the mechanisms of sex differentiation
Autor/es:
CARLOS STRÜSSMANN; M KARUBE,; LEANDRO MIRANDA,; REINALDO PATIÑO; GUSTAVO M SOMOZA; D UCHIDA,; Y YAMASHITA
Libro:
Fish genetics and aquaculture biotechnology
Editorial:
Oxford & IBH Publishing/Science Publishers
Referencias:
Lugar: Enfield (USA); Año: 2004; p. 65 - 79
Resumen:
Summary: This paper discusses the methods of sex control and current knowledge of the mechanisms of gonadal sex differentiation in fishes. Although our understanding of sex differentiation in fishes has improved greatly in recent years, it is still insufficient to allow generalisations about its mechanisms or to develop practical, reliable and safe methods of sex control. The scarcity of information arises from the fact that studies on sex differentiation are generally conducted on a few traditional species and focus on a limited set of hypothesis. Therefore, the current knowledge does not account for the variation in the forms of sexuality expressed in fishes and for the various degrees of plasticity of phenotypic sex that are found among fishes. In order to broaden the discussion about the mechanisms of sex differentiation, we present here an overview of our studies on the sex differentiation of three species, the pejerrey (Odontesthes bonariensis), the channel catfish (Ictalurus punctatus), and the zebrafish (Danio rerio), and introduce some novel views about this process. The hypotheses being explored are that a) temperature-dependent sex determination/differentiation is under the control of the central nervous system, b) differential sex-linked distribution of cells expressing the estrogen receptor plays a role in early gonadal sex differentiation , and c) apoptosis is involved in the death of somatic or germ cells during sex differentiation.