Insulin-like growth factor I (IGF-I), IGF-II and type-I IGF receptor gene expression in the ovary of the laying hen

D. G. Armstrong, Charis Hogg

Research output: Contribution to journalArticlepeer-review

Abstract

Expression of genes encoding insulin-like growth factor I (IGF-I), insulin-like growth factor II (IGF-II) and type I insulin-like growth factor receptor (IGFr) was measured in theca and granulosa cells from the ovary of the laying hen, using an RNase protection assay. Expression of genes encoding IGF-I and -II was confined to theca tissue and expression was not detected in granulosa cells. In contrast, expression of genes encoding IGFr in granulosa cells was significantly greater than that in theca tissue. The 98 base IGF-II probe was similar to a region of the second coding exon of chicken IGF-II and produced multiple RNase-protected RNA hybrids. Theca RNA from follicles at all stages of development produced RNase-protected hybrids of size 98, 96 and 90 bases; however, an additional band (66 bases) was also observed in theca RNA from small yellow follicles. The stage of follicular development during which maximum amounts of the 66 base RNase-protected fragment was detected correlates with the stage at which small follicles are selected for recruitment into the follicular hierarchy. The results provide evidence for the involvement of IGFs in the intraovarian control of ovarian function in a non-mammalian species, and highlight the importance of IGF-II in this process.
Original languageEnglish
Pages (from-to)101-6
Number of pages6
JournalJournal of reproduction and fertility
Volume106
Issue number1
DOIs
Publication statusPublished - Jan 1996

Keywords

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Chickens/genetics
  • Chickens/metabolism
  • DNA Probes/genetics
  • Female
  • Gene Expression
  • Genetic Techniques
  • Granulosa Cells/metabolism
  • Insulin-Like Growth Factor I/genetics
  • Insulin-Like Growth Factor I/metabolism
  • Insulin-Like Growth Factor II/genetics
  • Insulin-Like Growth Factor II/metabolism
  • Molecular Sequence Data
  • Ovary/chemistry
  • Ovary/cytology
  • Oviposition/genetics
  • RNA, Messenger/metabolism
  • Receptor, IGF Type 1/genetics
  • Theca Cells/metabolism

Fingerprint Dive into the research topics of 'Insulin-like growth factor I (IGF-I), IGF-II and type-I IGF receptor gene expression in the ovary of the laying hen'. Together they form a unique fingerprint.

Cite this