Isolation of a subclass of nuclear proteins responsible for conferring a DNase I-sensitive structure on globin chromatin.
The globin gene is preferentially sensitive to digestion by DNase I in erythrocyte chromatin but not in brain, fibroblast, or oviduct chromatin. Elution of the erythrocyte chromatin with 0.35 M NaCl leads to no detectable change in the gross structure of individual nucleosomes; however, in this depleted chromatin the globin gene is no longer preferentially sensitive to DNase I. Reconstitution of the depleted chromatin with either the entire 0.35 M NaCl fraction or a subclass from this fraction greatly enriched in two high mobility group proteins (nos. 14 and 17) results in the successful reconstitution of DNase I sensitivity of the globin gene. For all of these preparations, the inactive ovalbumin gene exhibited no preferential sensitivity to DNase I. Reconstitution of the erythrocyte 0.35 M NaCl fraction with depleted brain chromatin resulted in no preferential sensitivity of the globin gene in brain chromatin; however, reconstitution of the brain 0.35 M NaCl fraction with depleted erythrocyte chromatin led to successful reconstitution of DNase I sensitivity of the globin gene. Thus, the eluted proteins responsible for conferring DNase I sensitivity are probably not tissue-specific and probably do not recognize specific DNA sequences.
D000818:Animals; D002467:Cell Nucleus / Q000032:analysis; D002642:Chick Embryo; D002843:Chromatin / Q000302:isolation & purification / Q000378:metabolism / Q000648:ultrastructure*; D002868:Chromosomal Proteins, Non-Histone / Q000302:isolation & purification*; D003851:Deoxyribonucleases / Q000378:metabolism*; D005796:Genes; D005914:Globins / Q000235:genetics*; D008836:Micrococcal Nuclease / Q000378:metabolism; D012965:Sodium Chloride
D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D012965:Sodium Chloride; D005914:Globins; D003851:Deoxyribonucleases; D008836:Micrococcal Nuclease