title: Analysis of inactive X chromosome structure by in situ nick translation.
abstract: Nick translation assays of fixed interphase female fibroblasts with tritiated nucleotides demonstrated a characteristic absence of label over sex chromatin. The chromatin bodies were nearly always peripheral in location and a ribbon of nick translatable DNA was detected between the sex chromatin and the nuclear envelope. High voltage electron microscopy indicated the possibility of a special nuclear envelope attachment region. The apparent resistance of sex chromatin to nick translation did not appear to be due to resistance to DNase I attack.
mesh_terms: D002478:Cells, Cultured; D002843:Chromatin / Q000648:ultrastructure; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D007399:Interphase; D008854:Microscopy, Electron; D014176:Protein Biosynthesis; D013942:Thymine Nucleotides / Q000378:metabolism; D014316:Tritium; D014960:X Chromosome / Q000378:metabolism / Q000648:ultrastructure*
chemical_list: D002843:Chromatin; D013942:Thymine Nucleotides; D014316:Tritium; D004259:DNA-Directed DNA Polymerase; C024157:thymidine 5'-triphosphate