Figure 1.

HAT and HMT activities are associated exclusively with macronuclei in Tetrahymena. (A) Unit gravity-purified macro- or micronuclei, isolated from logarithmically growing Tetrahymena, were labeled in the presence of ³H-acetylCoA, and total proteins were resolved on a 12% SDS/PAGE gel and examined by Coomassie staining (Left) or fluorography (Right). (B) Same as in A except that nuclei were labeled in the presence of ³H-AdoMet. (C) Acid-soluble polypeptides from either macro- or micronuclei were resolved on a 12% SDS/PAGE gel, transferred to a membrane support, and probed with antibody to the micronuclear-specific protein α (Left) or with antibody to the macronuclear-specific protein hv1 (Right).