Abstract:
microRNAs (miRNAs) have been shown to be closely involved in the control of melanogenesis and hair colour in mammals. Previous data also indicate that miR-143 regulates cell growth in melanoma. Here, we aimed to investigate the role of miR-143-5p in alpaca melanocytes. We found that miR-143-5p was highly expressed in the cytoplasm of alpaca melanocytes as demonstrated by an in situ hybridization assay. Prediction analysis revealed that miR-143-5p could regulate TGF-β-activated kinase 1 (TAK1) expression, which we confirmed by luciferase reporter assay, indicating that miR-143-5p controls TAK1 expression by directly targeting its 3\' untranslated region (UTR). miR-143-5p overexpression decreased TAK1 expression, which led to increased melanocyte migration and proliferation, and downregulation of microphthalmia-associated transcription factor (MITF), which regulates melanin production. These results support a functional role for miR-143-5p in regulating alpaca melanocyte migration, proliferation and melanogenesis through direct targeting of TAK1.