PUBLICATION

Cloning, regulation of mRNA expression and function of a new isoform of Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) in the zebrafish ovary

Authors
Wang, Y., Wong A.O., and Ge, W.
ID
ZDB-PUB-030911-6
Date
2003
Source
Endocrinology   144(11): 4799-4810 (Journal)
Registered Authors
Keywords
none
MeSH Terms
  • Amino Acid Sequence/genetics
  • Animals
  • Base Sequence/genetics
  • Cells, Cultured
  • Cellular Senescence/drug effects
  • Chorionic Gonadotropin/pharmacology
  • Cloning, Molecular*
  • Female
  • Follistatin/metabolism
  • Gene Expression/drug effects
  • Gene Expression Regulation*
  • Isomerism
  • Molecular Sequence Data
  • Neuropeptides/genetics
  • Neuropeptides/physiology*
  • Neurotransmitter Agents/genetics*
  • Oocytes/drug effects
  • Oocytes/physiology
  • Ovarian Follicle/cytology
  • Ovarian Follicle/physiology
  • Ovary/cytology
  • Ovary/metabolism*
  • Pituitary Adenylate Cyclase-Activating Polypeptide
  • Pituitary Gland/chemistry
  • RNA, Messenger/metabolism*
  • Receptors, Vasoactive Intestinal Peptide/genetics
  • Receptors, Vasoactive Intestinal Peptide/metabolism
  • Receptors, Vasoactive Intestinal Peptide, Type II
  • Time Factors
  • Tissue Distribution
  • Tissue Extracts/pharmacology
  • Zebrafish
  • Zebrafish Proteins
PubMed
12959988 Full text @ Endocrinology
Abstract
Increasing evidence suggests that pituitary adenylate cyclase-activating polypeptide (PACAP) acts as a local factor in the ovary of mammals. In non-mammalian vertebrates, although the expression of PACAP has also been demonstrated in the ovary, the information on its functions and regulation is limited. In the present study, we identified a new type of PACAP, zfPACAP38-2, from the zebrafish ovary. The precursor of GHRH-zfPACAP38-2 consists of 175 amino acids with only 64% homology with another type of zebrafish PACAP, zfPACAP38-1. RT-PCR analysis detected two messengers of zfPACAP38-2 in the zebrafish ovary. The short product was more abundant and it encodes zfPACAP38-2 only, while the long form codes for both zfPACAP38-2 and GHRH. Using a primary culture of zebrafish follicle cells, we demonstrated that gonadotropin (hCG and goldfish pituitary extract) significantly stimulated zfPACAP38-2 expression within 2 h; however, the effect decreased to the control level after 8 h of treatment. The stimulation of zfPACAP38-2 expression by gonadotropin could be mimicked by cAMP analogs and forskolin but suppressed by H89 (10 micro M), suggesting the involvement of cAMP-PKA signaling pathway. We also examined the expression of PACAP receptor VPAC2-R in the zebrafish ovary. Unlike zfPACAP38-2 which showed a trend of increase during follicle development, the expression of VPAC2-R mRNA in the follicles showed no significant stage-dependent variation, and its expression in the follicle cells did not respond to gonadotropin treatment. Our studies further demonstrated that synthetic zfPACAP38-2 stimulated oocyte maturation and increased the expression of follistatin in zebrafish ovarian follicle cells. These results suggest that zfPACAP38-2 is a potential ovarian factor that mediates gonadotropin actions in paracrine/autocrine manners, and its functional roles are likely, to some extent, related to the ovarian activin/follistatin system.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping