TABLE 1.

Overview of the different animal models.

Models	Age	Description	Phenotype
MSTN KO	8 weeks	FVB mice harboring a constitutive deletion of the third MSTN exon	Hypertrophy
mTrFS	6 weeks	C57Bl/6 transgenic mice overexpressing the human FS 288 specifically in skeletal muscle	Hypertrophy
pM1-hFS288	14 weeks	Plasmid coding for the human FS 288 fused to the c-myc tag was transfected into TA muscle of C57Bl/6 mice which were euthanized 17 days later	Hypertrophy
sActRIIB 1x	8 weeks	C57Bl/6 mice treated with 1 injection of 10 mg/kg sActRIIB or PBS and euthanized 48 h after the injection	Hypertrophy
sActRIIB 2x	8–9 weeks	C57Bl/6 mice treated with 2 injections of 10 mg/kg sActRIIB or PBS, with injections being 48 h apart, and euthanized 48 h after the last injection	Hypertrophy
sActRIIB 4x	8–9 weeks	C57Bl/6 mice treated with 4 injections of 10 mg/kg sActRIIB or PBS, with injections being 48 to 72 h apart, and euthanized 48 h after the last injection	Hypertrophy
pcDNA-MSTN	8 weeks	Plasmid coding for the murine MSTN transfected into TA muscle of FVB mice which were harvested 14 days later	Atrophy
DEXA	8 weeks	FVB mice treated by a daily subcutaneous injection of 5 mg/kg DEXA for 4 days	Atrophy
Pak1 KO	8–9 weeks	C57Bl/6 mice presenting a whole-body 2 kb deletion of the genomic Pak1 DNA	None