GGA1kd cells exhibit defective insulin response.

(A) C2C12 cells treated with control and Gga1 (Golgi associated, gamma adaptin ear containing, ARF binding protein 1) siRNAs were stimulated by 0, 0.1, and 1 nM insulin for 5 min. Insulin signaling was then examined using anti-phospho AKT serine/threonine kinase 1 (AKT1) and anti-pan AKT1-specific antibodies. (B) The quantification of the phospho-AKT1/total AKT1 ratio is indicated on the right bar graph. (C) Wild-type and Gga1kd C2C12 cells were subjected to differentiation in the absence or presence of the indicated concentrations of insulin in the medium for four days. The formation of myotubes was then analyzed. Error bars indicate the SD (n = 3). *. P P t-test.