Maximal expression of suppressors of cytokine signalling in the rat ovary occurs in late pregnancy

Anderson, Stephen T., Isa, Naajia N. M., Barclay, Johanna L., Waters, Michael J. and Curlewis, Jon D. (2009) Maximal expression of suppressors of cytokine signalling in the rat ovary occurs in late pregnancy. Reproduction, 138 3: 537-544. doi:10.1530/REP-08-0425

Author Anderson, Stephen T.
Isa, Naajia N. M.
Barclay, Johanna L.
Waters, Michael J.
Curlewis, Jon D.
Title Maximal expression of suppressors of cytokine signalling in the rat ovary occurs in late pregnancy
Journal name Reproduction   Check publisher's open access policy
ISSN 1470-1626
Publication date 2009-06
Year available 2009
Sub-type Article (original research)
DOI 10.1530/REP-08-0425
Volume 138
Issue 3
Start page 537
End page 544
Total pages 8
Place of publication Bristol, United Kingdom
Publisher BioScientifica
Collection year 2010
Language eng
Subject C1
920106 Endocrine Organs and Diseases (excl. Diabetes)
070702 Veterinary Anatomy and Physiology
110306 Endocrinology
0604 Genetics
Formatted abstract
Maintenance of the rodent corpus luteum (CL) during pregnancy requires prolactin receptor (PRLR) signal transduction via STAT5. At the end of pregnancy, prostaglandin F (PGF) induces luteal regression through many mechanisms, including downregulation of PRLR signaling. We have previously shown that a PGF analog upregulates suppressors of cytokine signaling (SOCS) proteins in the CL of day 19 pregnant rats leading to reduced STAT5 signaling. Here, we examined endogenous SOCS expression and STAT5 signaling in the rat ovary during normal pregnancy and luteolysis. The mRNA expression of Socs1, Socs2, and Socs3 and related cytokine- inducible SH2-containing protein (Cish) was low in early pregnancy (day 7), but significantly increased at mid-pregnancy (days 10 and 13) associated with increased endogenous tyrosine phosphorylation (TyrP) of STAT5. In support of the notion that these changes are due to increasing placental lactogen levels at this time, we found that treatment with exogenous PRL on day 7 increased TyrP of STAT5 and induced SOCS mRNA expression, except Socs3. After mid-pregnancy, further significant increases in Socs3 and Cish mRNA expression were observed. Such changes in mRNA expression correlated with protein levels, with protein levels of both SOCS3 and CISH being maximal in late pregnancy (days 19–21). In addition, a significant reduction in TyrP of STAT5 was first observed on day 20, with a further substantial decrease on day 21. Therefore, these results are consistent with the hypothesis that increased SOCS expression in the rat ovary during late pregnancy reduces STAT5 signaling, which may be important in PGF-induced luteolysis. 
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 6 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 7 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Fri, 04 Sep 2009, 15:32:53 EST by Cameron Harris on behalf of School of Biomedical Sciences