Fig. 3. Coomassie Blue-stained SDS–polyacrylamide gel of CCR4-FLAG preparations. The band marked with the asterisks (CCR4-FLAG*) lacks ∼100 amino acids of the extreme N-terminus of CCR4 as determined by western analysis. Loss of this region of CCR4 had no effect on CCR4 in vivo activity (Draper et al., 1994). Molecular weight standards are indicated on the left and the respective CCR4-FLAG mutants are indicated.