Supplementary Figure S1.

Validation of sActRIIB activity in vivo. Biological activity of sActRIIB therapy in vivo was determined through gene and protein quantification of targets downstream of ActRIIB. (A) Expression of the transgelin gene (Tagln; synonym, Sm22) is regulated by nuclear translocation of phosphorylated Smad after ActRIIB activation. sActRIIB therapy in mdx mice resulted in lower Tagln gene expression. (B) Levels of phosphorylated Akt were significantly greater in muscles after sActRIIB therapy. *P < 0.05.