ADP-ribosylation of histones and acid-soluble, high mobility group like chromosomal proteins from Physarum polycephalum

Abstract

Nuclei from the cellular slime mould Physarum polycephalum were incubated with [32P]NAD. The chromosomal basic proteins were acid extracted and separated by two-dimensional polyacrylamide gel electrophoresis. After autoradiography the poly(ADP-ribosylated) proteins were identified. Histone H1 was the major acceptor. Histones H2B and H2A were significantly modified, although to a lesser extent than H1. In addition, the acid-soluble, high mobility group-like proteins AS-2 and AS-3 and the protein A-24 showed some modification. Histones H3 and H4 were not modified. The pattern of ADP-ribosylation did not change with NAD concentrations between 1 and 100 μM NAD.