Molecular cloning and expression analysis of Fshr and Lhr in relation to Fshb and Lhb subunits during the period of temperature-dependent sex determination in pejerrey Odontesthes bonariensis

SHINODA, T; MIRANDA, L.A.; OKUMA, K.; HATTORI, R.S.; FERNANDINO, J.I.; YOSHIZAKI, G; SOMOZA, G.M.; STRÜSSMANN, C.A.

MOLECULAR REPRODUCTION AND DEVELOPMENT

Wiley

Año: 2010 vol. 77 p. 521 - 532

1040-452X

In this study, we cloned and characterized the follicle stimulating hormone receptor(Fshr) and luteinizing hormone receptor (Lhr) cDNAs of pejerrey Odontesthesbonariensis, a species with temperature-dependent sex determination (TSD), andanalyzed their expression in relation to Fshb and Lhb subunits during gonadogenesisat temperatures producing only females (17°C, FPT), both sexes (25°C, MixPT), andonly males (29°C, MPT). The pejerrey Fshr cDNA had 3,069 bp for a mature protein of694 amino acids (aa) and a signal peptide of 22 aa; the Lhr cDNA had 2,936 bp for amature protein of 676 aa and a signal peptide of 25 aa. With the exception of Lhr in fishat the MPT, all genes showed significant increases and/or peaks of expression beforehistological differentiation of the gonads regardless of temperature. Larvae at the FPThad lower Fshb and Lhb but higher Lhr expression during theTSDperiod than those atthe MPT; a clear pattern could not be ascertained for Fshr. At the MixPT, Fshb, Lhb,and Lhr mRNA increased in approximately half of the fish during TSD and sexdifferentiation and the sex ratio was 55.2% male. Based on the above results, it issuggested that animals with high Fshb and Lhb and low Lhr values represent putativemales. These evidences, together with other studies, suggest that temperature maysignal through the pituitary (differential expression of Fshb and Lhb) down to thegonads (differential expression of Lhr), probably affecting the regulation of steroidogenesisduring the TSD process of pejerrey.