Western blot using EIF3F polyclonal antibody (Cat # PAB10008) shows detection of endogenous EIF3F in lysates from both control HeLa cells (lane 1) and HeLa cells transformed with the kinase cdk11 (lane 2). Cdk11 is responsible for phosphorylating EIF3F in vivo. After SDS-PAGE and transfer, the membrane was probed with the primary antibody diluted to 1 : 200. This antibody recognizes both phosphorylated and non-phosphorylated eIF3f. Personal Communication, Jiaqi Shi, Univ. Arizona, Tucson, AZ.