Abstract:
:The nucleosomal repeat lengths of bulk chromatin and the chromatin of transcriptionally active and inactive genes were analyzed in two mouse cell lines and adult mouse spleens. The adult beta-globin gene exhibits a nucleosomal repeat length approximately 11 base pairs longer than (i) an inactive embryonic globin gene, epsilon y3; (ii) an immunoglobulin heavy chain gene, Cmu; and (iii) the bulk chromatin in murine erythroleukemia cell line DS19. The repeat length of the Cmu gene was approximately 14 base pairs longer than that of the adult beta-globin or epsilon y3 genes in the IgM-producing cell line M104E. The chromatin of several inactive genes had repeat lengths less than or equal to bulk chromatin. Individual genes were shown to vary in repeat length among the cell types examined. In addition, genes that exhibited an increased nucleosomal spacing were digested to mononucleosomes more rapidly than bulk chromatin or inactive genes with shorter repeats. Increased repeat length was also correlated with an increased sensitivity to DNase I. Thus, increased nucleosomal spacing may be a property of transcriptionally active genes or genes with the potential for transcription.
journal_name
Proc Natl Acad Sci U S Aauthors
Smith RD,Seale RL,Yu Jdoi
10.1073/pnas.80.18.5505subject
Has Abstractpub_date
1983-09-01 00:00:00pages
5505-9issue
18eissn
0027-8424issn
1091-6490journal_volume
80pub_type
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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