When cultured myocytes from patients with OB/T2D (n=5) were examined in parallel with those from the normal subjects (n=2), the basal phosphorylation levels of PKB, p70s6K, p42/p44 MAPKs and p90RSK1 were significantly lower (p<0.001) in the cells from patients with OB/T2D compared to those from the normal subjects (Fig. 2). Here, RPS6KA1 is linked to type 2 diabetes mellitus.