ZFIN ID: ZDB-PUB-010131-32
Roles of the activin regulatory system in fish reproduction
Ge, W.
Date: 2000
Source: Canadian journal of physiology and pharmacology   78(12): 1077-1085 (Journal)
Registered Authors: Ge, Wei
Keywords: activin, inhibin, follistatin, fish, reproduction, follicle stimulating hormone, polymerase chain-reaction, messenger RNA expression, TGF-beta family, GTH-II-beta, rainbow trout, in vitro, molecular cloning, Oncorhynchus mykiss, Carassius auratus
MeSH Terms:
  • Activin Receptors
  • Activins
  • Animals
  • Autocrine Communication
  • Cloning, Molecular
  • Fishes/physiology*
  • Follistatin
  • Glycoproteins/metabolism
  • Gonadotropins/metabolism
  • Inhibins/biosynthesis
  • Inhibins/genetics
  • Inhibins/physiology*
  • Left-Right Determination Factors
  • Paracrine Communication
  • Receptors, Growth Factor/genetics
  • Receptors, Growth Factor/physiology
  • Recombinant Proteins/biosynthesis
  • Reproduction/physiology*
  • Transforming Growth Factor beta/metabolism
  • Zebrafish Proteins*
PubMed: 11149384 Full text @ Can. J. Physiol. Pharmacol.
Activin (betaAbetaA, betaAbetaB, and betaBbetaB) is a dimeric growth factor with diverse biological activities in vertebrate reproduction. Activin exerts its actions by binding to its specific type II and type I receptors. The activity of activin is regulated by follistatin, its binding protein, and the antagonists inhibin and antivin. All major components of the activin-inhibin-follistatin system have been identified in fish except the alpha subunit of inhibin. Using goldfish as a model, we have demonstrated that activin is expressed in the pituitary and the recombinant goldfish activin B has novel inverse effects on the expression of GTH beta subunits. Activin increases the mRNA level of GTH-Ibeta while significantly suppressing the expression of GTH-IIbeta. We have also demonstrated the expression of activin and its receptors in the goldfish and zebrafish ovary. Using an in vitro ovarian follicle incubation as the system, we have investigated the involvement of the activin system in the process of final oocyte maturation. Our evidence clearly indicates that activin has potent effect of promoting final oocyte maturation, and that it may play a role in mediating the stimulatory effect of pituitary gonadotropin in the event of oocyte maturation.