Figure 5. RingoA interacts with Cdk2 and regulates Cdk2 kinase activity in testis.

(a) Immunoprecipitates from WT testis lysates using RingoA or Cdk2 antibodies and control IgGs were analysed by immunoblotting for RingoA. The arrowhead indicates RingoA and the asterisks IgGs. (b) WT and KO 18 dpp old testis lysates were immunoprecipitated with Cdk2 antibodies or control IgGs. The immunoprecipitates were assayed in an in vitro kinase assay using γ-³²P-ATP and Rb protein as a substrate (upper row) and the gel was stained with Coomassie (middle row). An aliquot of the immunoprecipitates was analysed by immunoblotting with Cdk2 antibodies (bottom row). The phosphorylated Rb protein was quantified using ImageJ and was referred to the amount of RB protein detected in the Coomassie staining. The experiments were reproduced two to three times. The uncropped images are shown in Supplementary Fig. 7.