GSE66542
Nuclear myosin 1 contributes to a chromatin landscape compatible with RNA polymerase II transcription activation
Nuclear myosin 1c (NM1) is emerging as regulator of transcription and chromatin organization. Using a genome-wide approach we report here that NM1 binds across the mammalian genome with occupancy peaks at class II gene promoters, correlating with distributions of RNA Polymerase II (Pol II) and active epigenetic marks. We show that NM1 synergizes with polymerase-associated actin to maintain active Pol II at gene promoters. NM1 also co-localizes with the nucleosome remodeler SNF2h at class II promoters where they assemble together with WSTF as part of the B-WICH complex to remodel chromatin. Following B-WICH assembly, NM1 mediates physical recruitment of the histone acetyl transferase PCAF and the histone methyl transferase Set1/Ash2 to maintain and preserve H3K9acetylation and H3K4trimethylation for active transcription. We propose a novel genome-wide mechanism where myosin synergizes with Pol II-associated actin to link the polymerase machinery with permissive chromatin for transcription activation. Overall design: Association of nuclear myosin 1 (NM1) with the genome in mouse embryonic fibroblasts