Figure 7.

Transcriptional Interaction Partners of CDK6

(A) An anti-STAT3 co-immunoprecipitation (co-IP) was performed with Stat3^Δ/Δ, Cdk6^−/−, Cdk6^+/+, and Cdk6^+/++Cdk6 cell extracts and immunoblotted for STAT3 and CDK6.

(B) An anti-c-JUN co-IP was performed with c-Jun^Δ/Δ, Cdk6^−/−, Cdk6^+/+, and Cdk6^+/++Cdk6 cell extracts and immunoblotted for c-JUN and CDK6.

(C and D) Vegf-A mRNA levels of (C) c-Jun^Δ/Δ versus c-Jun^Δ/Δ+Cdk6 and (D) Stat3^Δ/Δ versus Stat3^Δ/Δ+Cdk6 p185^BCR-ABL-transformed cells were analyzed with qPCR (n ≥ 3; Stat3^Δ/Δversus Stat3^Δ/Δ+Cdk6: ^∗p = 0.025).

(E and F) p16^INK4a mRNA levels of (E) c-Jun^Δ/Δ versus c-Jun^Δ/Δ+Cdk6 and (F) Stat3^Δ/Δ versus Stat3^Δ/Δ+Cdk6 p185^BCR-ABL-transformed cells were analyzed with qPCR (n ≥ 3; c-Jun^Δ/Δ versus c-Jun^Δ/Δ+Cdk6: ^∗∗p = 0.008).

(G) A potential interaction between CDK6 and c-JUN or STAT3 was analyzed in Cdk6^+/++Cdk6 cells with ChIP-Re-ChIP experiments at the promoter regions of Vegf-A and p16^INK4a. Antibodies used for ChIP (1st AB) and Re-ChIP (2nd AB) are shown on the right.

(H–K) Vegf-A (H and I) and p16^INK4a (J and K) mRNA levels of Cyclin D1/2/3^−/− MEFs versus cyclin D1/2/3^−/− MEFs enforced expressing CDK6 as well as cyclin D1/2/3^+/+ MEFs versus cyclin D1/2/3^+/+ MEFs enforced expressing CDK6 were analyzed with qPCR.

Error bars indicate the mean ± SEM. See also Figure S7.