Nuclear localization and phosphorylation of three 25-kilodalton rat stress proteins

The nuclear localization and phosphorylation of three 25-kilodalton rat myoblast stress proteins were examined. Data obtained in these analyses led to the following conclusions: (i) all three proteins become localized in the nucleus of stressed cells, (ii) two of the proteins are modified by phosphorylation, and (iii) phosphorylation occurs exclusively on serine residues.