FIG. 2.

Yng1p is a stable component of the NuA3 HAT complex. (A and B) Whole-cell extracts from the indicated strains were immunoprecipitated (IP) with αFLAG resin and either were assayed for HAT activity on free HeLa histones (panel A; the fluorogram and Coomassie brilliant blue stain of an SDS-PAGE of these histones are shown) or were Western blotted and probed for Sas3HA₃ (B). (C) Whole-cell extracts from a strain expressing HA-tagged Yng1p was purified by Ni²⁺-NTA agarose and MonoQ ion-exchange chromatography. The MonoQ fractions were assayed for HAT activity on free histones by SDS-PAGE and fluorography and for the presence of Yng1HA₃ by Western blotting.