title: Identification of a novel microRNA important for melanogenesis in alpaca (Vicugna pacos).
abstract: The molecular mechanisms underlying the formation of coat colors in animals are poorly understood. Recent studies have demonstrated that microRNA play important roles in the control of melanogenesis and coat color in mammals. In a previous study, we characterized the miRNA expression profiles in alpaca skin with brown and white coat color and identified a novel miRNA (named lpa-miR-nov-66) that is expressed significantly higher in white skin compared to brown skin. The present study was conducted to determine the functional roles of this novel miRNA in the regulation of melanogenesis in alpaca melanocytes. lpa-miR-nov-66 is predicted to target the soluble guanylate cyclase (sGC) gene based on presence of a binding site in the sGC coding sequence (CDS). Overexpression of lpa-miR-nov-66 in alpaca melanocyes upregulated the expression of sGC both at the mRNA and protein level. Overexpression of lpa-miR-nov-66 in melanocyes also resulted in decreased expression of key melanogenic genes including tyrosinase (TYR), tyrosinase related protein 1 (TYRP1), and microphthalmia transcription factor (MITF). Our ELISA assays showed increased cyclic guanosine monophosphate (cGMP) but decreased cyclic adenosine monophosphate (cAMP) production in melanocytes overexpressing lpa-miR-nov-66. In addition, overexpression of lpa-miR-nov-66 also reduced melanin production in cultured melanocytes. Results support a role of lpa-miR-nov-66 in melanocytes by directly or indirectly targeting , which regulates melanogenesis via the cAMP pathway.
authors.forename: S
authors.initials: S
authors.lastname: Yang
authors.forename: R
authors.initials: R
authors.lastname: Fan
authors.forename: Z
authors.initials: Z
authors.lastname: Shi
authors.forename: K
authors.initials: K
authors.lastname: Ji
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Herrid
authors.forename: Q
authors.initials: Q
authors.lastname: Zhang
authors.forename: J
authors.initials: J
authors.lastname: Yao
authors.forename: G W
authors.initials: GW
authors.lastname: Smith
authors.forename: C
authors.initials: C
authors.lastname: Dong
mesh_terms: D000818:Animals; D001483:Base Sequence; D002161:Camelids, New World / Q000235:genetics / Q000502:physiology*; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000502:physiology; D006152:Cyclic GMP / Q000502:physiology; D005786:Gene Expression Regulation / Q000235:genetics / Q000502:physiology; D006162:Guanylate Cyclase / Q000235:genetics / Q000502:physiology; D006200:Hair Color / Q000235:genetics / Q000502:physiology*; D008543:Melanins / Q000378:metabolism*; D008544:Melanocytes / Q000166:cytology / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics / Q000502:physiology*; D051739:Microphthalmia-Associated Transcription Factor / Q000235:genetics / Q000502:physiology; D008969:Molecular Sequence Data; D014442:Monophenol Monooxygenase / Q000235:genetics / Q000502:physiology; D010088:Oxidoreductases / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D012880:Skin Pigmentation / Q000235:genetics / Q000502:physiology*
chemical_list: C000604851:MIRN-nov-66 microRNA, Vicugna pacos; D008543:Melanins; D035683:MicroRNAs; D051739:Microphthalmia-Associated Transcription Factor; D000242:Cyclic AMP; D010088:Oxidoreductases; C064056:tyrosinase-related protein-1; D014442:Monophenol Monooxygenase; D006162:Guanylate Cyclase; D006152:Cyclic GMP