ZFIN ID: ZDB-PUB-090819-17
Perspectives on fish gonadotropins and their receptors
Levavi-Sivan, B., Bogerd, J., Mañanós, E.L., Gómez, A., and Lareyre, J.J.
Date: 2010
Source: General and comparative endocrinology   165(3): 412-437 (Review)
Registered Authors: Levavi-Sivan, Berta
Keywords: estradiol, 11-ketotestosterone, follicle-stimulating hormone, luteinizing hormone, pituitary, recombinant, FSH receptor, LH receptor
MeSH Terms:
  • Animals
  • Female
  • Fishes/metabolism*
  • Fishes/physiology
  • Gonadotropins/genetics
  • Gonadotropins/metabolism*
  • Gonadotropins/physiology
  • Hypothalamo-Hypophyseal System/metabolism
  • Hypothalamo-Hypophyseal System/physiology
  • Male
  • Phylogeny
  • Promoter Regions, Genetic
  • Receptors, Gonadotropin/genetics
  • Receptors, Gonadotropin/metabolism*
  • Receptors, Gonadotropin/physiology
  • Seasons
PubMed: 19686749 Full text @ Gen. Comp. Endocrinol.
Teleosts lack a hypophyseal portal system and hence neurohormones are carried by nerve fibers from the preoptic region to the pituitary. The various cell types in the teleost pituitary are organized in discrete domains. Fish possess two gonadotropins (GtH) similar to FSH and LH in other vertebrates; They are heterodimeric hormones that consist of a common alpha subunit noncovalently associated with a hormone-specific beta subunit. In recent years the availability of molecular cloning techniques allowed the isolation of the genes coding for the GtH subunits in 56 fish species representing at least fourteen teleost orders Advanced molecular engineering provides the technology to produce recombinant GtHs from isolated cDNAs. Various expression systems have been used for the production of recombinant proteins. Recombinant fish GtHs were produced for carp, seabream, channel and African catfish, goldfish, eel, tilapia, zebrafish, Manchurium trout and Orange-spotted grouper. The hypothalamus in fishes exerts its regulation on the release of the GtHs via several neurohormones such as GnRH, dopamine, GABA, PACAP, IGF-I, norepinephrine, NPY, kisspeptin, leptin and ghrelin. In addition, gonadal steroids and peptides exert their effects on the gonadotropins either directly or via the hypothalamus. All these are discussed in details in this review. In mammals, the biological activities of FSH and LH are directed to different gonadal target cells through the cell-specific expression of the FSH receptor (FSHR) and LH receptor (LHR), respectively, and the interaction between each gonadotropin-receptor couple is highly selective. In contrast, the bioactivity of fish gonadotropins seems to be less specific as a result of promiscuous hormone-receptor interactions, while FSHR expression in Leydig cells explains the strong steroidogenic activity of FSH in certain fish species.