Western Blot: MEK1/2 Phosphospecific Antibody [GTX48615] - Western Blot of NIH 3T3 cell lysates showing specific immunolabeling of the ~45kDa MEK 1/2 protein phosphorylated at Ser218 and Ser222. The cells were either serum starved (Control) or incubated in the presence of serum (Serum). Immunolabeling of an additional band at ~95kDa was also observed.