Differential splicing of three gonadotropin-releasing hormone transcripts in the ovary of seabream (Sparus aurata).
Previous studies demonstrated the presence of high-affinity GnRH binding sites and compounds with GnRH-like activity in the ovary of seabream, Sparus aurata, providing evidence for the role of GnRH as a paracrine/autocrine regulator of ovarian function in this species. In the present study, the expression of three forms of GnRH (salmon, chicken-II, and seabream) genes in this marine teleost species was demonstrated for the first time. Moreover, there is evidence for differential splicing and intronic expression of cGnRH-II and sbGnRH. Treatment of seabream follicle-enclosed oocytes with salmon GnRH stimulated reinitiation of oocyte meiosis, whereas chicken GnRH-II treatment was without effect. Novel information was also provided about organization of cGnRH-II and seabream GnRH transcripts, confirming that GnRH gene organization is maintained through evolution, despite changes in the size and sequence of exons and introns.
Nabissi
M
M
Dipartimento di Scienze Morfologiche e Biochimiche Comparate, University of Camerino, 62032 Camerino (MC), Italy.
Soverchia
L
L
Polzonetti-Magni
A M
AM
Habibi
H R
HR
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002645:Chickens; D005260:Female; D005786:Gene Expression Regulation; D007987:Gonadotropin-Releasing Hormone / Q000235:genetics* / Q000494:pharmacology; D008540:Meiosis; D008969:Molecular Sequence Data; D009865:Oocytes / Q000187:drug effects / Q000502:physiology; D010053:Ovary / Q000502:physiology*; D010473:Perciformes / Q000502:physiology*; D012326:RNA Splicing; D013045:Species Specificity; D014158:Transcription, Genetic
D007987:Gonadotropin-Releasing Hormone