INFLUENZA-VIRUS MATRIX PROTEIN M1 INTERACTION WITH HISTONES

Nitrocellulose and polyvinyldifluoride membrane filters were used to s tudy in vitro the interactions of influenza virus A and B with canine, monkey, and chicken cell proteins by blotting analysis. It was demons trated that M1 selectively binds to nuclear proteins electrophoretical ly identical to chromatin histone proteins of 32 and 14 kDa. Isolated M1 effectively binds to purified histones H2A, H2B, H3, and H4 and les s to H1. The M1-histone interaction takes place in a broad pH range (6 .0-9.0) and does not depend on the presence of Ca2+, Mg2+, or EDTA in the medium. Binding declines at pH similar to 5.3 and is completely in hibited at high ionic strength (400 ml NaCl and higher), indicating an ionic nature of interaction. The involvement of M1 in the nuclear pha se of influenza virus replication is discussed.