Researchers in this article showed that the co-repressor CtBP1 is present on the myogenin promoter with repressive histone marks. They found that preventing CtBP1 Ser158 phosphorylation induces CtBP1 accumulation in the nuclei and abrogates the activation of myogenin and AChR expression. The findings show a molecular mechanism for the coordinated control of chromatin modifications and muscle gene expression by presynaptic neurons via a PAK1/CtBP1 pathway. The Diagenode Bioruptor was used to shear cells in the study.