Objective:To study the role of the striated muscle activator of Rho signaling（STARS）in insulin resistance induced by palmitic acid in muscle cells as well as the potential mechanisms modulating STARS expression. Methods:L6 myoblasts were incubated with palmitic acid to establish a model for insulin resistance. The effects of STARS on insulin resistance in L6 muscle cells were observed and its potential mechanisms of action were further explored by inducing its over-expression and knockdown. Levels of STARS

SRF

MKL1

AKT

IRS-1 and GLUT4 m RNA and protein were detected by RT-PCR and Western blot

respectively. Results:Compared with those in the control group

STARS m RNA and protein levels were significantly increased in muscle cells in the PA（palmitic acid）and pc DNA/STARS（STARS over-expression）groups. Levels of IRS-1

GLUT4 and AKT m RNA were significantly decreased in the pc DNA/STARS group. In addition

serine phosphorylation of AKT and GLUT4 protein levels were decreased and serine phosphorylation of IRS-1 was increased. In contrast

STARS knockdown produced the opposite results in above parameters. MKL1 and SRF m RNA and protein levels were unaffected by these interventions. Conclusion:STARS is closely related with insulin sensitivity

while without significant changes of its downstream target MKL1 and SRF. It might play a role in insulin resistance by modulating post-translational modification of MKL1 and SRF or through other signaling pathways. Further investigations are thus needed.