Methylation of Arg3 on H4 tails is required for the formation of an active chromatin domain. (A) ChIP analysis of dimethyl H4R3 at the β-globin locus in stable MEL cell lines transduced with pSuper vector or shPRMT1 vector in the presence of 1.5% DMSO for 3 days. The precipitated DNA was analyzed by real-time qPCR. (B) ChIP analysis of the H3K9/K14ac and acH4 patterns at HS2, the β^maj-promoter, and the inactive necdin promoter comparing the parental and the shPRMT1-transduced MEL cells treated with 1.5% DMSO for 3 days. (C-D) ChIP assays of CBP and PCAF at the HS2 enhancer, the β^maj-globin promoter, the MyoD promoter, and the actin promoter in stable MEL cell clones transduced with the vector control or shPRMT1 in the presence of 1.5% DMSO for 3 days. (E) Western blot analysis of proteins from MEL cells stably transduced with pSuper vector or PRMT1 shRNA vector with antibodies as indicated. Shown are the mean ± SDM of 3 independent experiments.