Progesterone receptor A
The progesterone receptor A (PR-A) is one of three known isoforms of the progesterone receptor (PR), the main biological target of the endogenous progestogen sex hormone progesterone.[1][2] The other isoforms of the PR include the PR-B and PR-C.[1][2]

PR-A is 164 residues shorter than PR-B in humans[3] and anywhere from 128-165 residues shorter in other organisms.[4] Each isoform binds its natural ligand, progesterone, but also demonstrate the ability to bind a number of other agonists including norethindrone, a synthetic progestin.[5]

Expression and overexpression
PR-A and PR-B are generally expressed in equal ratios,[6] but PR-A is expressed in larger amounts in uterine stromal cells normally[7]. A spike in PR-A expression in the myometrium has been observed to initiate parturition in placental mammals.[8]
PR-A is the isoform most commonly observed to be overexpressed in human breast cancer and patients with PR-A rich carcinomas, as opposed to patients with PR-B rich carcinomas, have faster recurrence rates.[9]
See also
References
- ^ a b Jacobsen BM, Horwitz KB (2012). "Progesterone receptors, their isoforms and progesterone regulated transcription". Mol. Cell. Endocrinol. 357 (1–2): 18–29. doi:10.1016/j.mce.2011.09.016. PMC 3272316. PMID 21952082.
- ^ a b Scarpin KM, Graham JD, Mote PA, Clarke CL (2009). "Progesterone action in human tissues: regulation by progesterone receptor (PR) isoform expression, nuclear positioning and coregulator expression". Nucl Recept Signal. 7: e009. doi:10.1621/nrs.07009. PMC 2807635. PMID 20087430.
- ^ Graham, J Dinny; Clarke, Christine L (October 2002). "Progesterone receptors - animal models and cell signaling in breast cancer: Expression and transcriptional activity of progesterone receptor A and progesterone receptor B in mammalian cells". Breast Cancer Research. 4 (5): 187–190. doi:10.1186/bcr450. ISSN 1465-542X. PMC 138742. PMID 12223122.
- ^ Conneely, O (November 2000). "Progesterone receptors in reproduction: functional impact of the A and B isoforms". Steroids. 65 (10–11): 571–577. doi:10.1016/S0039-128X(00)00115-X. PMID 11108861.
- ^ Madauss, Kevin P.; Deng, Su-Jun; Austin, Robert J. H.; Lambert, Millard H.; McLay, Iain; Pritchard, John; Short, Steven A.; Stewart, Eugene L.; Uings, Ian J.; Williams, Shawn P. (2004-06-01). "Progesterone Receptor Ligand Binding Pocket Flexibility: Crystal Structures of the Norethindrone and Mometasone Furoate Complexes". Journal of Medicinal Chemistry. 47 (13): 3381–3387. doi:10.1021/jm030640n. ISSN 0022-2623. PMID 15189034.
- ^ Graham, J Dinny; Clarke, Christine L (October 2002). "Progesterone receptors - animal models and cell signaling in breast cancer: Expression and transcriptional activity of progesterone receptor A and progesterone receptor B in mammalian cells". Breast Cancer Research. 4 (5): 187–190. doi:10.1186/bcr450. ISSN 1465-542X. PMC 138742. PMID 12223122.
- ^ Bulun, Serdar E.; Cheng, You-Hong; Yin, Ping; Imir, Gonca; Utsunomiya, Hiroki; Attar, Erkut; Innes, Joy; Julie Kim, J. (March 2006). "Progesterone resistance in endometriosis: Link to failure to metabolize estradiol". Molecular and Cellular Endocrinology. 248 (1–2): 94–103. doi:10.1016/j.mce.2005.11.041. PMID 16406281.
- ^ Cope, Dominique; Monsivais, Diana (2022-04-27). "Progesterone Receptor Signaling in the Uterus Is Essential for Pregnancy Success". Cells. 11 (9): 1474. doi:10.3390/cells11091474. ISSN 2073-4409. PMC 9104461. PMID 35563781.
- ^ Timmermans-Sprang, Elpetra P. M.; Gracanin, Ana; Mol, Jan A. (2017-04-13). "Molecular Signaling of Progesterone, Growth Hormone, Wnt, and HER in Mammary Glands of Dogs, Rodents, and Humans: New Treatment Target Identification". Frontiers in Veterinary Science. 4: 53. doi:10.3389/fvets.2017.00053. ISSN 2297-1769. PMC 5389977. PMID 28451590.