MicroRNA MiR-17 retards tissue growth and represses fibronectin expression

• Published in: Nature cell biology Vol. 11; no. 8; pp. 1031 - 1038
• Main Authors: Deng, Zhaoqun, Lee, Daniel Y, Shatseva, Tatiana, Jeyapalan, Zina, Zhang, Yaou, Yee, Siu-Pok, Yang, Burton B, Shan, Sze Wan, Du, William W, Siragam, Vinayakumar, Xuan, Jim W
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.08.2009; Nature Publishing Group
• Subjects: Adhesion; Animals; Base Sequence; Biomedical and Life Sciences; Breast cancer; Cancer Research; Cell Adhesion; Cell adhesion & migration; Cell Biology; Cell Line; Cell Line, Tumor; Cell Proliferation; Developmental Biology; Female; Fibronectins; Fibronectins - genetics; Flow Cytometry; Gene Expression Regulation; Growth; Humans; Kidney - metabolism; Kidney - pathology; letter; Life Sciences; Liver - metabolism; Liver - pathology; Male; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; MicroRNAs; MicroRNAs - genetics; Molecular Sequence Data; Myocardium - metabolism; Myocardium - pathology; Physiological aspects; Reverse Transcriptase Polymerase Chain Reaction; RNA; Sequence Homology, Nucleic Acid; Spleen - metabolism; Spleen - pathology; Stem Cells; Tissues; Transfection; Transgenic animals; Canada; United States; Toronto Ontario Canada; Ontario Canada
• ISSN: 1465-7392; 1476-4679
• DOI: 10.1038/ncb1917

MicroRNAs (miRNAs) are single-stranded regulatory RNAs, frequently expressed as clusters. Previous studies have demonstrated that the six-miRNA cluster miR-17∼92 has important roles in tissue development and cancers. However, the precise role of each miRNA in the cluster is unknown. Here we show that overexpression of miR-17 results in decreased cell adhesion, migration and proliferation. Transgenic mice overexpressing miR-17 showed overall growth retardation, smaller organs and greatly reduced haematopoietic cell lineages. We found that fibronectin and the fibronectin type-III domain containing 3A (FNDC3A) are two targets that have their expression repressed by miR-17, both in vitro and in transgenic mice. Several lines of evidence support the notion that miR-17 causes cellular defects through its repression of fibronectin expression. Our single miRNA expression assay may be evolved to allow the manipulation of individual miRNA functions in vitro and in vivo. We anticipate that this could serve as a model for studying gene regulation by miRNAs in the development of gene therapy.