Posttranscriptional regulation of osteoglycin by microRNA miR-155 during myogenesis

Author(s)

Paula Paccielli Freire

• Document type: Master's Dissertation
• Press: Botucatu. 2020-04-02.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Biociências. Botucatu
• Defense date: 2016-02-23
• Advisor: Robson Francisco Carvalho; Maeli Dal Pai Silva

Abstract

Skeletal myogenesis is a highly regulated process in which mononucleated precursor cells, the myoblasts, undergo proliferation and differentiation. Upon differentiation, the cells withdraw from the cell cycle, migrate, align with each other, and subsequently fuse to form terminally differentiated multinucleated myotubes. Myogenesis is a wellcharacterized program of cellular differentiation sensitive to autocrine and paracrine signaling events. Previous reports have identified the protein osteoglycin (Ogn) as an important component of the skeletal muscle secretome that is differentially expressed during muscle development. However, the posttranscriptional regulation of osteoglycin by microRNAs during myogenesis is completely unknown. Bioinformatics analysis showed that mir-155 potentially targeted Ogn transcript at region 3´ UTR. In the present study, we tested the hypothesis that miR-155 inhibits Ogn expression to regulate skeletal myogenesis. Luciferase assay, RT-qPCR and Western blot analyses confirmed that miR-155 regulates Ogn at 3’UTR region. The differential expression of miR-155 correlates with the differential expression of myogenic molecular markers Myh2 and Myog; moreover, the miR-155 transfections decreased cellular migration and proliferation in myoblasts, and decreased myotubes formation. The Ogn knockdown deregulates the expression of myogenic molecular markers Myh2, Myod, and Myog mRNA expression in myotubes and decreased myoblasts proliferation. These results reveal a novel pathway in which miR-155 inhibits Ogn expression to regulate migration, proliferation and differentiation during myogenesis. (AU)

• FAPESP's process: 14/13783-6 - Posttranscriptional regulation of osteoglicyn by miR-155 during myogenesis
• Grantee: Paula Paccielli Freire-Barguil
• Support Opportunities: Scholarships in Brazil - Master