P-selectin, also called GMP-140, CD62, or selectin P, is a 140-kD adhesion molecule, expressed at the surface of activated cells, that mediates the interaction of activated endothelial cells or platelets with leukocytes.
NCBI Summary:
SELP is a platelet alpha-granule membrane protein of molecular weight 140,000 that redistributes to the plasma membrane during platelet activation and degranulation. It is a member of a family of adhesion/homing receptors. Alternative splice variants may occur but are not well documented
General function
Cell adhesion molecule
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Cellular localization
Plasma membrane
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Ovarian function
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Increased circulating soluble P-selectin in polycystic ovary syndrome. Yildiz BO et al. OBJECTIVE: To determine whether the P-selectin-von Willebrand factor (vWF) pathway is altered in patients with polycystic ovary syndrome (PCOS). DESIGN: Case-control study. SETTING(S): Tertiary care academic medical center. PATIENT(S): Thirty-two normal glucose-tolerant patients with PCOS and 21 age- and body mass index-matched healthy women were prospectively enrolled. All the patients with PCOS had clinical and/or biochemical hyperandrogenism and chronic oligoanovulation, and 89% had polycystic ovaries on ultrasound. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Soluble P-selectin (sP-selectin), vWF, total T, sex hormone-binding globulin, total cholesterol, high-density lipoprotein cholesterol, triglycerides, fasting glucose and insulin, 2-hour glucose, and homeostatic model assessment-insulin resistance. RESULT(S): Soluble P-selectin levels were significantly higher in patients with PCOS compared with controls (58.7 +/- 19.0 vs. 45.3 +/- 15.0 ng/mL), whereas PCOS and control groups had similar vWF levels (46.7 +/- 24.2 vs. 39.5 +/- 22.3, respectively). There was no correlation between sP-selectin and anthropometric measurements or any of the androgen, lipid, or insulin resistance parameters. CONCLUSION(S): Our results suggest increments in the circulating sP-selectin concentrations associated with unaltered vWF levels in PCOS. Increased sP-selectin might potentially contribute to the future risk of cardiovascular disease in patients with PCOS.
Expression regulated by
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Ovarian localization
Oocyte, Theca, Stromal cells
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Molecular Characterization of Equine P-Selectin (CD62P) and Its Regulation in Ovarian Follicles During the Ovulatory Process Sayasith K, et al .
Ovulation is accompanied by a marked infiltration of leukocytes into thecal layers after the gonadotropin surge. P-selectin is known to play a critical role in the initial steps of leukocyte recruitment from the bloodstream during inflammation. Thus the objective was to investigate the potential regulation of P-selectin by gonadotropins in equine preovulatory follicles. The full-length equine P-selectin cDNA was cloned by a combination of RT-PCR and 5'- and 3'-rapid amplification of cDNA ends. Results showed that equine P-selectin cDNA encodes a 829-amino acid protein that is highly conserved when compared to the human protein (80% identity). Semiquantitative RT-PCR/Southern blot analyses were performed to study the regulation of P-selectin transcript in preovulatory follicles isolated during estrus at 0, 12, 24, 30, 33, 36 and 39 h after an ovulatory dose of hCG (ovulation occurs between 39 and 42 h post-hCG in this model). Results showed that levels of P-selectin mRNA remained very low or undetectable throughout the ovulatory process in extracts prepared from the granulosa cell layer. In contrast, a significant increase in P-selectin transcript was observed between 30 and 39 post-hCG in extracts obtained from thecal layers (P < 0.05). Likewise, immunohistochemistry revealed an increase of immunoreactive P-selectin protein in the vascular endothelium present in theca layers of follicles isolated 36 and 39 h post-hCG. Thus, this study describes for the first time the primary structure of equine P-selectin and the regulation of P-selectin transcript and protein in follicular thecal endothelial cells prior to ovulation.