miR-148 regulates Mitf in melanoma cells

• Published in: PloS one Vol. 5; no. 7; p. e11574
• Main Authors: Haflidadóttir, Benedikta S, Bergsteinsdóttir, Kristín, Praetorius, Christian, Steingrímsson, Eiríkur
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 14-07-2010; Public Library of Science (PLoS)
• Subjects: 3' Untranslated regions; 3' Untranslated Regions - genetics; Analysis; Animals; Apoptosis; Binding Sites; Biochemistry; Blotting, Western; Cancer; Cell cycle; Cell growth; Cell Line; Cell proliferation; Cloning; Conserved sequence; Developmental Biology; Gene expression; Gene Expression Regulation, Neoplastic - genetics; Gene Expression Regulation, Neoplastic - physiology; Genomes; Genomics; Humans; Medicine; Melanocytes; Melanoma; Melanoma - genetics; Melanoma - metabolism; Mice; Microphthalmia-associated transcription factor; Microphthalmia-Associated Transcription Factor - genetics; Microphthalmia-Associated Transcription Factor - metabolism; MicroRNA; MicroRNAs; MicroRNAs - genetics; MicroRNAs - metabolism; miRNA; Molecular biology; Molecular Biology/mRNA Stability; Mutagenesis; Mutation; Oncology/Skin Cancers; Polymerase Chain Reaction; Post-translation; Protection and preservation; Proteins; Reverse Transcriptase Polymerase Chain Reaction; Splicing; Transcription factors; Tumors
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0011574

The Microphthalmia associated transcription factor (Mitf) is an important regulator in melanocyte development and has been shown to be involved in melanoma progression. The current model for the role of Mitf in melanoma assumes that the total activity of the protein is tightly regulated in order to secure cell proliferation. Previous research has shown that regulation of Mitf is complex and involves regulation of expression, splicing, protein stability and post-translational modifications. Here we show that microRNAs (miRNAs) are also involved in regulating Mitf in melanoma cells. Sequence analysis revealed conserved binding sites for several miRNAs in the Mitf 3'UTR sequence. Furthermore, miR-148 was shown to affect Mitf mRNA expression in melanoma cells through a conserved binding site in the 3'UTR sequence of mouse and human Mitf. In addition we confirm the previously reported effects of miR-137 on Mitf. Other miRNAs, miR-27a, miR-32 and miR-124 which all have conserved binding sites in the Mitf 3'UTR sequence did not have effects on Mitf. Our data show that miR-148 and miR-137 present an additional level of regulating Mitf expression in melanocytes and melanoma cells. Loss of this regulation, either by mutations or by shortening of the 3'UTR sequence, is therefore a likely factor in melanoma formation and/or progression.