In yeast, the SAGA complex and Gcn5 perform this action, which is enhanced by Trichostatin A or sodium butyrate in vivo.
The circadian regulator CLOCK appears to perform this enzymatic process, and shows homology to the MYST family, which also has this function. This is not tumor suppression, but SV40 T antigen inactivates a protein complex with this function called p3000/CBP. In yeast, the SAGA complex and Gcn5 perform this action, which is enhanced by Trichostatin A or sodium butyrate in vivo. This action increases binding affinity with a 110- residue loop of alpha helices called a (*) bromodomain, and can remove the positive charge of a lysine residue. HDACs reverse this action, which usually modifies the N-terminal lysines of H3 and H4 histones. By reducing the strength of DNA-histone interactions, this action makes chromatin more transcriptionally active. For 10 points, name this post-translational modification of histones by HATs, which adds to amino acids a functional group often bound to coenzyme A.
The circadian regulator CLOCK appears to perform this enzymatic process, and shows homology to the MYST family, which also has this function.
histone  acetylation