{"doi":"10.17615/bprh-6g14","title":"Conformation of ovalbumin and globin genes in chromatin during differential gene expression","abstract":"Micrococcal nuclease and DNase I were used to study changes in the chromatin conformation of ovalbumin and globin genes during differential expression of these sequences. Oviduct nuclei, obtained from estrogen-treated chicks or chicks withdrawn from the hormone for 3, 4, or 6 days, were incubated with micrococcal nuclease until 1 to 3% of the DNA was rendered acid-soluble. The resulting DNA fragments then were separated into four size classes. In the stimulated oviducts, the concentration of the ovalbumin gene in mononucleosome-length DNA (165 to 200 base pairs) was 6-fold greater than in the fraction containing DNA fragments >1300 base pairs in length. This selective cleavage decreased progressively as a function of estrogen withdrawal time and correlated temporally with a decline in the concentration of oviduct nuclear estrogen receptors. The expressed globin genes in immature erythrocyte nuclei were also cleaved preferentially by micrococcal nuclease, whereas the transcriptionally silent globin sequences in mature erythrocyte nuclei were not. The globin genes in both immature and mature erythrocyte nuclei were destroyed by DNase I 3 times faster than the greater part of the nuclear DNA. To determine if the globin genes in the mature erythrocyte were cleaved preferentially by DNase I, nuclei were incubated with this enzyme until 1 to 3% of the DNA was rendered acid-soluble. The resulting DNA fragments then were separated into four size classes. The concentration of globin genes in the size class containing the smallest DNA fragments (less than 300 base pairs) from both immature and mature erythrocyte nuclei was about 6-fold greater than in undigested DNA, and about 15-fold greater than in the fraction containing DNA fragments >1200 base pairs in length. These results suggest that the micrococcal nuclease sensitive conformation of the ovalbumin and globin genes in chromatin is dynamically related to the expression of these sequences. The DNase I sensitive structure as determined by both nucleolytic destruction and cleavage, in contrast, remains associated with globin sequences following their inactivation.","journal":"UNC Libraries","year":2022,"id":311921,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9467,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1006033,"name":"K.S. Bloom","orcid":null,"position":1,"is_corresponding":false},{"id":1008929,"name":"J.N. Anderson","orcid":null,"position":0,"is_corresponding":true}],"reference_count":0,"raw_metadata":null,"created_at":"2026-07-19T00:33:32.327694Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}