Selenium is an essential trace element that is incorporated as selenocysteine into the primary structure of
selenoproteins. There are at least 10 animal selenoproteins. Nutritional deficiency of selenium decreases selenoprotein
concentrations and leads to pathologic conditions. Most of the known
selenoproteins are members of the glutathione peroxidase or iodothyronine deiodinase families. Hill et al. (1996) stated
that selenoprotein P (SEPP1) is a major selenoprotein that is not a member of those families. It is an extracellular
glycoprotein that is present in several isoforms and is the only selenoprotein known to contain multiple selenocysteine
residues. It is a heparin-binding protein that appears to be associated with endothelial cells and has
been implicated as an oxidant defense in the extracellular space.
NCBI Summary:
This gene encodes a selenoprotein that is predominantly expressed in the liver and secreted into the plasma. This selenoprotein is unique in that it contains multiple selenocysteine (Sec) residues per polypeptide (10 in human), and accounts for most of the selenium in plasma. It has been implicated as an extracellular antioxidant, and in the transport of selenium to extra-hepatic tissues via apolipoprotein E receptor-2 (apoER2). Mice lacking this gene exhibit neurological dysfunction, suggesting its importance in normal brain function. Sec is encoded by the UGA codon, which normally signals translation termination. The 3' UTRs of selenoprotein mRNAs contain a conserved stem-loop structure, designated the Sec insertion sequence (SECIS) element, that is necessary for the recognition of UGA as a Sec codon, rather than as a stop signal. The mRNA for this selenoprotein contains two SECIS elements. The use of alternative polyadenylation sites, one located in between the two SECIS elements, results in two populations of mRNAs containing either both (predominant) or just the upstream SECIS element (PMID:27881738). Alternatively spliced transcript variants have also been found for this gene. [provided by RefSeq, Oct 2018]
General function
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Cellular localization
Secreted
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Elevated circulating Selenoprotein P levels in patients with polycystic ovary syndrome. Temur M et al. (2021) Selenoprotein P (SeP), an hepatokine that is primarily produced by liver, has been reported to affect glucose metabolism. In this study, we aimed to measure and compare serum SeP values in patients with polycystic ovary syndrome (PCOS) and a healthy control group, and to investigate whether there was a relationship between SeP values and insulin resistance in patients with PCOS. This prospective case-control study included 40 patients with PCOS and 39 healthy women (non-PCOS) matched for age and body mass index. SeP levels were significantly higher in the PCOS group compared with the healthy controls (7.48 ± 3.80 vs. 5.17 ± 3.20 mg/ml, p = .005). Serum insulin, hs-CRP, HOMA-IR, FBG, total-testosterone, and free-testosterone levels were higher in women with PCOS than in controls. In an unadjusted model and after adjusting for potential confounders, SeP had increased odds for PCOS (p = .007). ROC curve analysis showed that the area under the ROC curves were 0.691 (95% CI: 0.576-0.806, p < .003) for SeP levels. The optimal cut-off value of SeP for detecting PCOS was ≥5.87 mgl/ml. We showed, for the first time, that serum SeP levels were increased significantly in PCOS, Our results suggest that there is a potential link between PCOS and SeP levelsIMPACT STATEMENTWhat is already known on this subject? Selenoprotein deficiency causes various dysfunctions associated with oxidative stress, but recent studies found that increased SeP levels were associated with insulin resistance. Circulating SeP levels have been found to be increased in patients with type 2 diabetes mellitus (T2DM).What the results of this study add? Our study is the first in the literature to examine the relationship between SeP levels and the presence of PCOS. Serum SeP levels were increased significantly in PCOS.What the implications are of these findings for clinical practice and/or further research? SeP seemed to have a role in PCOS. SeP can be used to predict metabolic disorders associated with PCOS and to determine treatment methods.//////////////////
Ovarian function
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Expression regulated by
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Ovarian localization
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This gene was found in a rat ovarian cDNA library (Unigene)