[Nuclear protein matrix from giant nuclei of Chironomus plumosus determinates polythene chromosome organization].
Giant nuclei from salivary glands of Chironomus plumosus were treated in situ with detergent, 2 M NaCl and nucleases in order to reveal residual nuclear matrix proteins (NMP). It was shown, that preceding stabilization of non-histone proteins with 2 mM CuCl2 allowed to visualize the structure of polythene chromosomes at every stage of the extraction of histones and DNA. Stabilized NPM of polythene chromosomes maintains their morphology and banding patterns, which is observed by light and electron microscopy, whereas internal fibril net or residual nucleoli are not found. In stabilized NPM of polythene chromosomes, topoisomerase IIalpha and SMC1 retain their localization that is typical of untreated chromosomes. NPM of polythene chromosomes also includes sites of DNA replication, visualized with BrDU incubation, and some RNA-components. So, we can conclude that structure of NPM from giant nuclei is equal to NPM from normal interphase nuclei, and that morphological features of polythene chromosomes depend on the presence of NMP.
Makarov
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MS
Chentsov
Iu S
IuS
D000818:Animals; D000951:Antigens, Neoplasm / Q000648:ultrastructure; D018797:Cell Cycle Proteins / Q000648:ultrastructure; D002466:Cell Nucleolus / Q000235:genetics / Q000648:ultrastructure*; D002683:Chironomidae / Q000235:genetics* / Q000648:ultrastructure; D002868:Chromosomal Proteins, Non-Histone / Q000648:ultrastructure; D002875:Chromosomes / Q000648:ultrastructure*; D004250:DNA Topoisomerases, Type II / Q000648:ultrastructure; D004268:DNA-Binding Proteins / Q000648:ultrastructure; D007399:Interphase; D007814:Larva / Q000166:cytology; D008854:Microscopy, Electron; D034521:Nuclear Matrix-Associated Proteins / Q000648:ultrastructure*; D012469:Salivary Glands / Q000648:ultrastructure*; D000098550:Structural Maintenance of Chromosome Protein 1
D000951:Antigens, Neoplasm; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D034521:Nuclear Matrix-Associated Proteins; D000098550:Structural Maintenance of Chromosome Protein 1; D004250:DNA Topoisomerases, Type II