Figure 1.

Specificity of the Polyclonal Anti-PhosphoSer13-Cdc37 Antibody

(A) Coomasie-stained SDS-PAGE of purified H-C-K and C-K complexes.

(B) Incubation of purified WT-Cdc37 expressed in E. coli with CK2 at 30°C shows a time-dependent specific signal from the α-pSer13-Cdc37 polyclonal antibody. No signal was observed with an S13A mutant. The blot was amido black-stained as a loading control. It has been shown elsewhere that Ser13 is the only site of phosphorylation by CK2 on Cdc37.

(C) Free Cdc37, Cdc37 in complex with Cdk4 (C-K) and Cdc37 in complex with Hsp90 and Cdk4 (H-C-K) expressed in insect cells are all phosphorylated on Ser13.