a highly homogeneous 145-base-pair fragment of double helical poly ( da-dt ) . poly ( da-dt ) was obtained by micrococcal nuclease digestion of a semisynthetic chromatin prepared from the nucleosome core histones ( h2a , h2b , h3 , h4 ) and the synthetic polydeoxyribonucleotide .
C1518457
nucleosome core
C0019646
h2a