title: Ultraviolet B radiation-stimulated urocortin 1 is involved in tyrosinase-related protein 1 production in human melanoma HMV-II cells.
abstract: Ultraviolet B (UVB) radiation stimulates cutaneous melanin pigmentation. The melanosomal enzyme tyrosinase-related protein 1 (TRP1) is involved in the modulation of pigment production in response to this stressor. Recent molecular and biochemical analyses have revealed the presence of corticotropin-releasing factor (CRF) and urocortin 1 (Ucn1), together with their corresponding receptors, in mammalian skin. Although CRF and Ucn1 are thought to have potent effects on the skin system, their possible roles and regulations have yet to be determined fully. Our previous findings in human melanoma HMV-II cells suggest that both CRF and Ucn1 regulate TRP1 gene expression via Nurr-1/Nur77, transcription factors that constitute the nuclear receptor 4a subgroup of orphan nuclear receptors. HMV-II cells were found to express mainly Ucn1 mRNA. This study aimed to explore the effects of UVB on Ucn1 mRNA and TRP1 protein levels in HMV-II cells. UVB (30 mJ/cm(2)) increased Nurr-1, Nur77, and Ucn1 mRNA levels. UVB also increased TRP1 protein levels. Ucn1 knockdown inhibited the UVB-induced increases in TRP1 protein levels. These data suggest that UVB-stimulated Ucn1 contributes to TRP1 production via the transcription of both Nurr-1 and Nur77. Ucn1, produced in melanoma cells, acts on melanoma cells themselves in an autocrine manner.
authors.affiliation: Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Watanuki
authors.affiliation: Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan; Department of Endocrinology, Metabolism, and Infectious Diseases, Hirosaki University School of Medicine & Hospital, 53 Hon-cho, Hirosaki, Aomori 036-8563, Japan. Electronic address: kkageyama@hkg.odn.ne.jp.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kageyama
authors.affiliation: Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan.
authors.forename: Shinobu
authors.initials: S
authors.lastname: Takayasu
authors.affiliation: Department of Dermatology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Matsuzaki
authors.affiliation: Health Care Center, Kochi University, Kochi, Kochi 780-8520, Japan.
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Iwasaki
authors.affiliation: Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Daimon
mesh_terms: D019898:Autocrine Communication / Q000235:genetics / Q000528:radiation effects*; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1 / Q000235:genetics / Q000378:metabolism; D057126:Nuclear Receptor Subfamily 4, Group A, Member 2 / Q000235:genetics / Q000378:metabolism; D010088:Oxidoreductases / Q000096:biosynthesis* / Q000235:genetics; D014158:Transcription, Genetic / Q000235:genetics / Q000528:radiation effects*; D014466:Ultraviolet Rays; D054832:Urocortins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D008562:Membrane Glycoproteins; C539821:NR4A1 protein, human; C539882:NR4A2 protein, human; D009363:Neoplasm Proteins; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D057126:Nuclear Receptor Subfamily 4, Group A, Member 2; C576814:UCN protein, human; D054832:Urocortins; D010088:Oxidoreductases; C489799:TYRP1 protein, human
keywords: Corticotropin-releasing factor; Nur77; Nurr-1; Tyrosinase-related protein 1; Urocortin 1