Mollusc gonadotropin-releasing hormone directly regulates gonadal functions: A primitive endocrine system controlling reproduction

Nicholas Treen, Naoki Itoh, Hanae Miura, Ippei Kikuchi, Takenori Ueda, Keisuke G. Takahashi, Takayoshi Ubuka, Kazutoshi Yamamoto, Peter J. Sharp, Kazuyoshi Tsutsui, Makoto Osada

Research output: Contribution to journalArticlepeer-review

42 Citations (Scopus)

Abstract

Gonadotropin-releasing hormone (GnRH) is central to the control of vertebrate reproductive cycles and since GnRH orthologs are also present in invertebrates, it is likely that the common ancestor of bilateral animals possessed a GnRH-like peptide. In order to understand the evolutionary and comparative biology of GnRH peptides we cloned the cDNA transcripts of prepro GnRH-like peptides from two species of bivalve molluscs, the Yesso scallop Patinopecten yessoensis and the Pacific oyster Crassostrea gigas. We compared their deduced uncleaved and mature amino acid sequences with those from other invertebrates and vertebrates, and determined their sites of expression and biological activity. The two molluscan GnRH sequences increased the number of known protostome GnRHs to six different forms, indicating the current classification of protostome GnRHs requires further revision. In both molluscs, RT-PCR analysis showed that the genes were highly expressed in nervous tissue with lower levels present in peripheral tissues including the gonads, while immunocytochemistry, using anti-octopus GnRH-like peptide, demonstrated the presence of GnRH-like peptide in neural tissue. Putative scallop GnRH-like peptide stimulated spermatogonial cell division in cultured scallop testis, but the scallop GnRH-like peptide did not stimulate LH release from cultured quail pituitary cells. This is the first report of the cloning of bivalve GnRH-like peptide genes and of molluscan GnRH-like peptides that are biologically active in molluscs, but not in a vertebrate.

Original languageEnglish
Pages (from-to)167-172
Number of pages6
JournalGeneral and Comparative Endocrinology
Volume176
Issue number2
DOIs
Publication statusPublished - 2012 Apr 1

Keywords

  • Functional evolution
  • GnRH
  • LH release
  • Molluscs
  • Neuropeptides
  • Spermatogenesis

ASJC Scopus subject areas

  • Animal Science and Zoology
  • Endocrinology

Fingerprint Dive into the research topics of 'Mollusc gonadotropin-releasing hormone directly regulates gonadal functions: A primitive endocrine system controlling reproduction'. Together they form a unique fingerprint.

Cite this