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Nuclear matrix proteins are carried within peripheral material of mitotic chromosomes

Y S Chentsov1, V V Burakov, M I Kosykh

  • 1Lomonosov Moscow State University, Biological Faculty, Vorob'evy Gory, Russia.

Membrane & Cell Biology
|August 30, 2000
PubMed

Insights

Autoimmune sera bind to nuclear structures and mitotic chromosomes. These antibodies target specific nuclear matrix proteins, suggesting their role in transferring these proteins to daughter nuclei during cell division.

Area of Science:

  • Cell Biology
  • Immunology
  • Molecular Biology

Background:

  • Autoimmune sera can provide valuable tools for identifying cellular components.
  • Understanding nuclear structure and function is crucial in cell biology.

Purpose of the Study:

  • To identify the nuclear and chromosomal targets of autoimmune sera M-222 and M-260.
  • To investigate the role of nuclear matrix proteins in mitosis and cell division.

Main Methods:

  • Immunofluorescence microscopy was used to visualize antibody binding.
  • Chromatin removal using 2 M NaCl and DNase I.
  • Electron microscopy for ultrastructural analysis.
  • Immunoblotting to determine protein molecular masses.

Main Results:

  • Autoimmune sera bound to interphase nuclei and mitotic chromosomes, specifically excluding nucleolar cores.
  • After DNA and histone removal, antibody binding persisted, indicating targets within the nuclear matrix.
  • Electron microscopy confirmed antibody binding to the lamina, residual nucleoli, and intranuclear matrix.
  • Immunoblotting identified target proteins of 65 kDa (serum M-260) and 47/65 kDa (serum M-222), with M-222 binding only to the 65 kDa protein after chromatin removal.

Conclusions:

  • The study identifies specific nuclear matrix proteins as targets of autoimmune sera.
  • Peripheral chromosomal material is implicated in the transfer of nuclear matrix polypeptides to daughter nuclei during mitosis.

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