All lanes : Anti-Myosin light chain kinase (phospho S1760) antibody (ab200809) at 1/1000 dilutionLane 1 : Extracts of COS cells transfected with muscle Myosin light chain kinase, unstimulatedLane 2 : Extracts of COS cells transfected with muscle Myosin light chain kinase phosphorylated in vitro by 0.05 µg of PKALane 3 : Extracts of COS cells transfected with muscle Myosin light chain kinase phosphorylated in vitro by 0.05 µg of PKA with the non-phosphopeptide corresponding to the phosphopeptide immunogenLane 4 : Extracts of COS cells transfected with muscle Myosin light chain kinase phosphorylated in vitro by 0.05 µg of PKA with a generic phosphoserine-containing peptideLane 5 : Extracts of COS cells transfected with muscle Myosin light chain kinase phosphorylated in vitro by 0.05 µg of PKA with the phosphopeptide immunogenLane 6 : Extracts of COS cells transfected with muscle Myosin light chain kinase phosphorylated in vitro by 0.05 µg of PKASecondarygoat F(ab’)2 anti-rabbit IgG HRP