Figure 6.

Mediator kinase activity is selectively disrupted in MED12–mutant UF tumors. A–C, whole tissue lysates from three different patient-matched uterine fibroid tumor sets, including MED12 WT and MED12 Q43P (A), G44S (B), or L36R (C) were subjected to IP with MED12-specific antibodies. MED12-specific IPs were resolved by SDS-10% PAGE and processed by Western blot (WB) analysis using the indicated Mediator subunit-specific antibodies (top panels) or subjected to in vitro kinase assay prior to resolution by SDS-PAGE and PhosphorImager analyses (bottom panels). Input corresponds to 10% of tissue lysates used in IPs. ³²P-Labeled GST–CTD levels were quantified and expressed relative those obtained in kinase reactions with WT MED12/Mediator IPs. Note that insufficient sample material in C precluded analysis of CDK19 levels by WB.