SRP341456 PRJNA771407 Sumoylation of the human histone H4 tail inhibits p300-mediated transcription by RNA polymerase II in cellular extracts To confirm the negative crosstalk with SUMO in human cells, linear non-hydrolyzable genetic fusions of SUMO-H4 were generated in HEK293T cells and analyzed by western blotting and chromatin immunoprecipitation followed by high-throughput sequencing of the associated DNA (ChIP-seq).