Raft localized PKC-theta is phosphorylated and is activated. Phosphorylation of both tyrosine and serine-threonine residues is important in the regulation of PKC function. Six phosphorylation sites have been identified on PKC-theta: Y90, T219, T538, S676, S685, and S695. Phosphorylation of Y90 positively regulates NF-AT and NF-kB activation in T-cells. In mast cells Src family members Src and LYN have been shown to be involved in phosphorylating Y90 (Wang et al. 2012, Liu et al. 2001).