Insulin and gender: An insulin-like gene expressed exclusively in the androgenic gland of the male crayfish

Rivka Manor, Simy Weil, Shirley Oren, Lilah Glazer, Eliahu D. Aflalo, Tomer Ventura, Vered Chalifa-Caspi, Miri Lapidot, Amir Sagi

Research output: Contribution to journalArticlepeer-review

143 Scopus citations

Abstract

Members of the insulin family of hormones are generally not regarded as gender-specific, although there is sporadic evidence for the possible involvement of insulin pathways in sexual differentiation. In crustaceans, sexual differentiation is controlled by the androgenic gland (AG), an organ unique to males. To date, attempts to identify active AG factors in decapods through either classical purification methods or sequence similarity with isopod AG hormones have proven unsuccessful. In the present study, the first subtractive cDNA library from a decapod AG was constructed from the red-claw crayfish Cherax quadricarinatus. During library screening, an AG-specific gene, expressed exclusively in males even at early stages of maturation and termed Cq-IAG (C. quadricarinatus insulin-like AG factor), was discovered. In situ hybridization of Cq-IAG confirmed the exclusive localization of its expression to the AG. Following cloning and complete sequencing of the gene, its cDNA was found to contain 1445 nucleotides encoding a deduced translation product of 176 amino acids. The proposed protein sequence encompasses Cys residue and putative cleaved peptide patterns whose linear and 3D organization are similar to those of members of the insulin/insulin-like growth factor/relaxin family and their receptor recognition surface. The identification of Cq-IAG is the first report of a pro-insulin-like gene expressed in a decapod crustacean in a gender-specific manner. Its expression in a male-specific endocrine gland controlling sex differentiation supports the notion that insulin may have evolved in the context of regulating sexual differentiation.

Original languageEnglish
Pages (from-to)326-336
Number of pages11
JournalGeneral and Comparative Endocrinology
Volume150
Issue number2
DOIs
StatePublished - 15 Jan 2007

Keywords

  • Androgenic gland
  • Cherax quadricarinatus
  • Cq-IAG
  • Crayfish
  • Crustacea
  • Decapoda
  • Differential expression
  • Insulin-like
  • Suppression subtractive hybridization
  • cDNA library

ASJC Scopus subject areas

  • Animal Science and Zoology
  • Endocrinology

Fingerprint

Dive into the research topics of 'Insulin and gender: An insulin-like gene expressed exclusively in the androgenic gland of the male crayfish'. Together they form a unique fingerprint.

Cite this