PARENT SESSION
PLATFORM SESSION 8: REGULATION OF GONADOTROPINS AND THEIR RECEPTORS: I
Chair: Narayan, Prema¹, ¹
Co-chair: Rispoli, Louisa¹, ¹
Dover A-C
4:30 PM-6:30 PM

(57) THE FSH, LH, AND GROWTH HORMONE IN FEMALE AND MALE Trichogaster trichopterus CLONING AND SEQUENCING OF ITS cDNA AND ANALYSIS OF ITS mRNA EXPRESSION DURING OOGENESIS AND SUBSEQUENT TREATMENT WITH GnRH ANALOG.

Degani, G^1,2,3, Goldberg, D¹, Jackson, K¹, ¹ MIGAL, Kiryat Shmona, Israel² School of Science and Technology, Israel³ Faculty of Agricultural, Food and Environmental Quality Sciences, Rehovot, Israel

ABSTRACT- The relationship between gonadotropin releasing hormone (GnRH), oogenesis and biosynthesis of follicle stimulating hormone (FSH), luteinizing hormone (LH) and growth hormone (GH) has not been studied in blue gourami (Trichogaster trichopterus) model for multi-spawning and gonadal development of the female dependent on male behavior. The cDNA encoding the full-length FSH, LH and growth hormone from blue gourami was cloned by RACE-PCR, and the relationship between gonadal development, the effect of [D-Ala⁶, Pro⁹Net]-LHRH (GnRHa) and the mRNA levels of FSH, LH and GH in males and females was determined by means of RT-PCR. Results: There was approximately 30% similarity between the deduced amino acid sequences of FSH and LH. FSH was found similar to a greater extent to the striped-bass counterpart. Correspondingly, LH resembled the striped-bass LH to the greatest extent (84%). The full-length sequence of GH was determined from an 896-bp clone, which included a 38-bp poly(A) tail and most similar to Sparus aurata GH (86%). The transcription of FSH and LH initially showed a marked increase in the level that occurred during the high vitellogenesis and maturation stages. Higher GH mRNA levels were found in immature females, in high vitellogenesis and at maturation than in low-vitellogenesis. In males, appr. levels of FSH mRNA were significantly higher in mature males than they were in juveniles. However, a significantly higher level of LH mRNA was found only in the sexually active group as opposed to the sexually inactive group. The level of GH mRNA increased slightly during the process of maturation, but no significant differences were found between the groups studied. The levels of both FSH and LH transcripts in females injected with GnRHa were significantly higher than those of the control group. A non-significant difference was found between GH transcription. The deduced amino acid sequences of FSH, LH and GH were similar to species belonging to Order Perciformes. The effect of the GnRH on FSH and LH expression could be related to the fact that in a multi-spawning fish, when one batch of oocytes reaches final maturation another batch enters vitellogenesis concomitantly. In males, suggest that FSH may participate in spermatogenesis, whereas LH is more involved in spermiogenesis.

KEY WORDS: Anabantidae , fish, Growth Hormone, gonadotropins, gourami, pituitary