This Article Full Text Full Text (PDF) A retraction has been published All Versions of this Article: 147/2/687    most recent Author Manuscript (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Taylor, A. H. Articles by Bell, S. C. Search for Related Content PubMed PubMed Citation Articles by Taylor, A. H. Articles by Bell, S. C.

The Progesterone Receptor in Human Term Amniochorion and Placenta Is Isoform C

Preterm Birth Research Group, Reproductive Sciences, Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester, Leicestershire LE2 7LX, United Kingdom

Address all correspondence and requests for reprints to: Anthony Taylor, Preterm Birth Research Group Lecturer, Reproductive Sciences Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, P.O. Box 65, Leicester, Leicestershire LE3 7LX, United Kingdom. E-mail: aht3{at}le.ac.uk.

The mechanism that initiates human parturition has been proposed to be functional progesterone withdrawal whereby the 116-kDa B isoform of the progesterone receptor (PR-B) switches in favor of the 94-kDa A isoform (PR-A) in reproductive tissues. Recently other PR isoforms, PR-S, PR-C, and PR-M generated from the same gene have been identified and partially characterized. Using immunohistochemical, Western blotting, and RT-PCR techniques, evidence is provided that the major PR isoform present in human term fetal membranes (amnion and chorion) and syncytiotrophoblast of the placenta is neither of the classical nuclear PR-B or PR-A isoforms but is the N terminally truncated 60-kDa PR-C isoform. Evidence is also provided that the PR-C isoform resides in the cytoplasm of the expressing cell types. Data are also presented to show that PR-B, PR-A, and PR-S isoforms are essentially absent from the amnion and chorion, whereas PR isoforms A, B, C, and S are all present in the decidua, with PR-A being the major isoform. The syncytiotrophoblast of the placenta contains the cytoplasmic PR-C isoform but not PR-A, PR-B, or PR-S. The major PR isoform in the amnion, chorion, and placenta is PR-C, suggesting that the cytoplasmic PR-C isoform has a specific role in extraembryonic tissues and may be involved in the regulation of human parturition.

This article has been cited by other articles:

				E. E. Connor, M. J. Meyer, R. W. Li, M. E. Van Amburgh, Y. R. Boisclair, and A. V. Capuco Regulation of Gene Expression in the Bovine Mammary Gland by Ovarian Steroids J Dairy Sci, June 1, 2007; 90(13_suppl): E55 - E65. [Abstract] [Full Text] [PDF]

				G. Madsen, D. A. MacIntyre, S. Mesiano, and R. Smith Progesterone Receptor or Cytoskeletal Protein? Reproductive Sciences, April 1, 2007; 14(3): 217 - 222. [Abstract] [PDF]

				R. Shao, E. Egecioglu, B. Weijdegard, K. Ljungstrom, C. Ling, J. Fernandez-Rodriguez, and H. Billig Developmental and hormonal regulation of progesterone receptor A-form expression in female mouse lung in vivo: interaction with glucocorticoid receptors. J. Endocrinol., September 1, 2006; 190(3): 857 - 870. [Abstract] [Full Text] [PDF]

				A. Khatua, X. Wang, T. Ding, Q. Zhang, J. Reese, F. J. DeMayo, and B. C. Paria Indian Hedgehog, But Not Histidine Decarboxylase or Amphiregulin, Is a Progesterone-Regulated Uterine Gene in Hamsters Endocrinology, September 1, 2006; 147(9): 4079 - 4092. [Abstract] [Full Text] [PDF]