The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
Gene Review

POMC  -  proopiomelanocortin

Ovis aries

Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of POMC

  • We therefore investigated the changes in the relative proportions of cells expressing POMC, ACTH, and the CRH type 1 receptor (CRHR(1)) shortly before birth and during chronic placental insufficiency [1].
  • We conclude that in response to prolonged hypoxemia, there is differential regulation of POMC mRNA levels in the pars distalis and pars intermedia of the pituitary in fetal sheep [2].
  • In contrast, the elevated basal levels of POMC peptides in the HPD animals were not significantly increased by the hypoglycemia, but a significant elevation of plasma cortisol was seen [3].
  • Long-term hypoxia enhances proopiomelanocortin processing in the near-term ovine fetus [4].

High impact information on POMC

  • It may also act in a paracrine fashion to promote placental POMC gene expression [5].
  • In fetuses subjected to experimental induction of placental restriction, the prepartum surge in fetal cortisol is exaggerated, whereas pituitary POMC mRNA levels are decreased, and in vitro, unstimulated ACTH secretion is elevated in corticotrophs nonresponsive to CRH [1].
  • This study is the first to demonstrate subpopulations of corticotrophs in the fetal sheep pituitary that differentially express POMC, ACTH, and CRHR(1) and the separate effects of gestational age and placental restriction on these subpopulations of corticotrophs [1].
  • The prepartum surge in fetal plasma cortisol is essential for the normal timing of parturition in sheep and may result from an increase in the ratio of ACTH to proopiomelanocortin (POMC) in the fetal circulation [1].
  • Glucose infusion increased mRNA expression for POMC, but not for the anorectic neuropeptide CART, or the orexigenic neuropeptides NPY and AGRP, in the arcuate nucleus of the fetal hypothalamus [6].

Chemical compound and disease context of POMC

  • The increase in POMC mRNA levels in the pars distalis at 48 h of hypoxemia, despite a rise in plasma cortisol and without a change in corticosteroid-binding globulin, suggests altered regulation of HPA function at this time [2].

Biological context of POMC

  • These observations differ from the rat, in which CRF is the most potent of the ACTH-releasing factors and the only ACTH secretagogue which stimulates POMC gene expression and biosynthesis [7].
  • The current study sought to define the effects of altered adiposity on the expression of genes for neuropeptide Y (NPY), POMC, enkephalin (ENK), and melanin-concentrating hormone (MCH) [8].
  • A 295 base pair portion of the ovine POMC gene was isolated using polymerase chain reaction and sequenced [7].
  • Gene expression was decreased for cocaine- and amphetamine-regulated transcript (CART) in the ARC and VMH and for proopiomelanocortin in ARC during lactation [9].
  • Finally, we report that increase in corticotrope POMC transcripts during late gestation in the inferior AP requires an intact PVN [10].

Anatomical context of POMC


Associations of POMC with chemical compounds


Regulatory relationships of POMC

  • Cortisol attenuated (p < 0.05) the neuropeptide-induced increases in POMC mRNA, though AVP-stimulated POMC mRNA levels were significantly higher than in cells treated with cortisol alone [17].

Other interactions of POMC

  • The HPD lesion effectively destroyed the entire median eminence [no nerve terminals immunostained for tyrosine hydroxylase (TH) and gonadotropin-releasing hormone] and the adjacent arcuate nucleus (no perikarya immunostained for proopiomelanocortin or TH, and no cells expressed neuropeptide Y mRNA) [18].
  • No differences in the percentage of POMC cells containing CRF1 receptor hybridization signal were observed in the superior region of the anterior pituitary between PVN-Lx (89+/-8%) and SHAM (87+/-9%) [19].
  • In the neurointermediate lobe, POMC, PC1, and PC2 were ubiquitously expressed at all ages [20].
  • Total RNA was subjected to Northern analysis using specific complementary DNA probes to CRH and POMC, and specific message was normalized to actin mRNA content in each individual sample [21].
  • AVP treatment significantly increased the percentage of irACTH- and POMC-secreting cells in nonpregnant, but not in pregnant, ewes [22].

Analytical, diagnostic and therapeutic context of POMC

  • Ovine POMC messenger RNA (mRNA) levels were quantitated using this partial complementary DNA clone in a solution hybridization/nuclease protection assay with cytoplasmic RNA from sheep anterior pituitary primary cultures which had been treated with various combinations of ACTH secretagogues or with glucocorticoids for 18 h [7].
  • Adrenalectomy in fetal sheep significantly increased expression of CRH and POMC [16].
  • We used two-site immunoradiometric assays to separately measure high mol wt ACTH precursors (POMC and pro-ACTH) and ACTH-(1-39) in plasma of fetal sheep with chronic arterial and venous catheters [23].
  • The ratio of anterior pituitary POMC mRNA:18 S ribosomal RNA was also lower (p < 0.05) in the PR group (0.49 +/- 0.05) when compared with the control group (0.80 +/- 0.12) after 140 d of gestation [24].
  • As measured by Western blot analysis, the proportion of ACTH(1-39) to POMC and pro-ACTH (22 kDa) also increased significantly with developmental age [25].


  1. Subpopulations of Corticotrophs in the Sheep Pituitary during Late Gestation: Effects of Development and Placental Restriction. Farrand, K., McMillen, I.C., Tanaka, S., Schwartz, J. Endocrinology (2006) [Pubmed]
  2. Differential regulation of proopiomelanocortin messenger ribonucleic acid in the pars distalis and pars intermedia of the pituitary gland after prolonged hypoxemia in fetal sheep. Braems, G.A., Matthews, S.G., Challis, J.R. Endocrinology (1996) [Pubmed]
  3. Studies of the regulation of the hypothalamic-pituitary-adrenal axis in sheep with hypothalamic-pituitary disconnection. I. Effect of an audiovisual stimulus and insulin-induced hypoglycemia. Engler, D., Pham, T., Fullerton, M.J., Funder, J.W., Clarke, I.J. Neuroendocrinology (1988) [Pubmed]
  4. Long-term hypoxia enhances proopiomelanocortin processing in the near-term ovine fetus. Myers, D.A., Bell, P.A., Hyatt, K., Mlynarczyk, M., Ducsay, C.A. Am. J. Physiol. Regul. Integr. Comp. Physiol. (2005) [Pubmed]
  5. Maturation and activation of hypothalamic-pituitary adrenal function in fetal sheep. Challis, J.R., Brooks, A.N. Endocr. Rev. (1989) [Pubmed]
  6. Impact of glucose infusion on the structural and functional characteristics of adipose tissue and on hypothalamic gene expression for appetite regulatory neuropeptides in the sheep fetus during late gestation. Mühlhäusler, B.S., Adam, C.L., Marrocco, E.M., Findlay, P.A., Roberts, C.T., McFarlane, J.R., Kauter, K.G., McMillen, I.C. J. Physiol. (Lond.) (2005) [Pubmed]
  7. Ovine anterior pituitary proopiomelanocortin gene expression is not increased by ACTH secretagogues in vitro. Levin, N., Wallace, C., Bengani, N., Blum, M., Farnworth, P., Smith, A.I., Roberts, J.L. Endocrinology (1993) [Pubmed]
  8. Long-term alterations in adiposity affect the expression of melanin-concentrating hormone and enkephalin but not proopiomelanocortin in the hypothalamus of ovariectomized ewes. Henry, B.A., Tilbrook, A.J., Dunshea, F.R., Rao, A., Blache, D., Martin, G.B., Clarke, I.J. Endocrinology (2000) [Pubmed]
  9. Leptin secretion and hypothalamic neuropeptide and receptor gene expression in sheep. Sorensen, A., Adam, C.L., Findlay, P.A., Marie, M., Thomas, L., Travers, M.T., Vernon, R.G. Am. J. Physiol. Regul. Integr. Comp. Physiol. (2002) [Pubmed]
  10. Fetal sheep pituitary proopiomelanocortin in late gestation: effect of bilateral lesions of the paraventricular nucleus on regional and cellular messenger ribonucleic acid levels. Bell, M.E., Myers, T.R., McDonald, T.J., Myers, D.A. Endocrinology (1997) [Pubmed]
  11. Proopiomelanocortin processing in the anterior pituitary of the ovine fetus after lesion of the hypothalamic paraventricular nucleus. Bell, M.E., McDonald, T.J., Myers, D.A. Endocrinology (2005) [Pubmed]
  12. Hypothalamic gene expression in sheep for cocaine- and amphetamine-regulated transcript, pro-opiomelanocortin, neuropeptide Y, agouti-related peptide and leptin receptor and responses to negative energy balance. Adam, C.L., Archer, Z.A., Findlay, P.A., Thomas, L., Marie, M. Neuroendocrinology (2002) [Pubmed]
  13. Early decrease of proopiomelanocortin but not neuropeptide Y mRNA expression in the mediobasal hypothalamus of the ewe, during the estradiol-induced preovulatory LH surge. Pillon, D., Caraty, A., Fabre-Nys, C., Bruneau, G. Gen. Comp. Endocrinol. (2003) [Pubmed]
  14. Immunocytochemical localization of beta endorphin and gonadal steroid regulation of proopiomelanocortin messenger ribonucleic acid in the ewe. Whisnant, C.S., Curto, K., Goodman, R.L. Neuroendocrinology (1992) [Pubmed]
  15. Influence of food restriction on neuropeptide-Y, proopiomelanocortin, and luteinizing hormone-releasing hormone gene expression in sheep hypothalami. McShane, T.M., Petersen, S.L., McCrone, S., Keisler, D.H. Biol. Reprod. (1993) [Pubmed]
  16. Effect of fetal adrenalectomy on messenger ribonucleic acid for proopiomelanocortin in the anterior pituitary and for corticotropin-releasing hormone in the paraventricular nucleus of the ovine fetus. Myers, D.A., Ding, X.Y., Nathanielsz, P.W. Endocrinology (1991) [Pubmed]
  17. CRH and AVP-induced changes in synthesis and release of ACTH from the ovine fetal pituitary in vitro: negative influences of cortisol. Matthews, S.G., Challis, J.R. Endocrine (1997) [Pubmed]
  18. Hypothalamic control of photoperiod-induced cycles in food intake, body weight, and metabolic hormones in rams. Lincoln, G.A., Rhind, S.M., Pompolo, S., Clarke, I.J. Am. J. Physiol. Regul. Integr. Comp. Physiol. (2001) [Pubmed]
  19. Corticotropin-releasing factor receptor expression in the pituitary of fetal sheep after lesion of the hypothalamic paraventricular nucleus. Myers, D.A., Bell, M.E., McDonald, T.J., Myers, T.R. Endocrinology (1999) [Pubmed]
  20. Expression of proopiomelanocortin and prohormone convertase-1 and -2 in the late gestation fetal sheep pituitary. Bell, M.E., Myers, T.R., Myers, D.A. Endocrinology (1998) [Pubmed]
  21. Effect of implantation of dexamethasone adjacent to the paraventricular nucleus on messenger ribonucleic acid for corticotropin-releasing hormone and proopiomelanocortin during late gestation in fetal sheep. Myers, D.A., McDonald, T.J., Dunn, T.G., Moss, G.E., Nathanielsz, P.W. Endocrinology (1992) [Pubmed]
  22. Attenuation of corticotropin-releasing hormone and arginine vasopressin responsiveness during late-gestation pregnancy in sheep. Young, S.F., Rose, J.C. Biol. Reprod. (2002) [Pubmed]
  23. Development of adrenocorticotropin-(1-39) and precursor peptide secretory responses in the fetal sheep during the last third of gestation. Carr, G.A., Jacobs, R.A., Young, I.R., Schwartz, J., White, A., Crosby, S., Thorburn, G.D. Endocrinology (1995) [Pubmed]
  24. Placental restriction alters the functional development of the pituitary-adrenal axis in the sheep fetus during late gestation. Phillips, I.D., Simonetta, G., Owens, J.A., Robinson, J.S., Clarke, I.J., McMillen, I.C. Pediatr. Res. (1996) [Pubmed]
  25. Ontogeny of proopiomelanocortin posttranslational processing in the ovine fetal pituitary. Saoud, C.J., Wood, C.E. Peptides (1996) [Pubmed]
WikiGenes - Universities