In vivo ubiquitination assay in HES1 immunoprecipitates from U2OS cells transfected with either pCDNA3/siCTRL, FLAG‐RASSF1A/siCTRL, or FLAG‐RASSF1A/siRNF4 to assess Ub chain incorporation. Immunoprecipitates and Input lysates are probed with displayed antibodies. In the absence of RNF4, HES1 levels remain stable despite RASSF1A expression. See also Fig
EV2B and C.