Single-strand binding proteins from phage T4 and E. coli form higher order structures with poly(dT)

Abstract

Complexes of poly(dT) with gene 32 protein from phage T4 or E. coli single-strand binding protein were digested by nuclease P1 from Penicillum citrinum. Protected fragments were analyzed by gel electrophoresis. In both cases, a series of bands was obtained corresponding to multiples of a repeat unit whose size was about 80 nucleotides. Such protected fragments could not be detected under the same experimental conditions when poly(dA) was used instead of poly(dT). The formation of nucleosome-like structures is discussed in relation to the higher affinity exhibited by single-strand binding proteins towards poly(dT). © 1986 Société de Chimie biologique/Editions Scientifiques Elsevier, Paris.