Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1941660 | Biochemistry and Biophysics Reports | 2016 | 8 Pages |
•Myostatin is a key negative regulator of muscle development.•GASP-2 is a secreted glycoprotein known to interact with myostatin.•GASP-2 overexpression promotes proliferation and differentiation of myoblasts.•GASP-2 Knockdown decreases proliferation and differentiation of myoblasts.•Glycosylation is not required for GASP-2 inhibitor function of myostatin actions.
BackgroundGASP-2 is a secreted multi-domain glycoprotein known as a specific inhibitor of myostatin and GDF-11. Here we investigate the role of GASP-2 on myogenesis and the effect of its glycosylation on its activity.MethodsGASP-2 overexpression or knockdown by shRNAs were carried out on C2C12 myoblasts cells. In silico analysis of GASP-2 protein was performed to identify its glycosylation sites. We produced a mouse recombinant GASP-2 protein in a prokaryotic system to obtain a fully deglycosylated protein allowing us to study the importance of this post-translational modification on GASP-2 activity.ResultsBoth mature and deglycosylated GASP-2 proteins increase C2C12 proliferation and differentiation by inhibiting the myostatin pathway. In silico and western-blot analyses revealed that GASP-2 presents one consensus sequence for N-glycosylation and six potential sites of mucin-type O-glycosylation.ConclusionsGASP-2 promotes myogenesis and thus independently of its glycosylation.General significanceThis is the first report demonstrating that GASP-2 promotes proliferation and differentiation of myoblasts by inhibiting the canonical pathway of myostatin.