Human Genetics

, Volume 35, Issue 1, pp 27–34

Chromosomal constitution of nucleolus-associated chromatin in man

  • A. Stahl
  • M. Hartung
  • A. M. Vagner-Capodano
  • C. Fouet
Original Investigations

DOI: 10.1007/BF00295616

Cite this article as:
Stahl, A., Hartung, M., Vagner-Capodano, A.M. et al. Hum Genet (1976) 35: 27. doi:10.1007/BF00295616

Summary

Use of specific stains permits analysis of the frequency of nucleolus-associated heterochromatin in chromosomes 1 and 9 from human fibroblasts. In 81% of interphase nuclei the heterochromatic segment of both No. 1 chromosomes is associated with the nucleolus, while in 19% only one heterochromatic segment shows such an association with the other occupying a random position in the nucleoplasm. The nucleolar association of chromosome 9 heterochromatin is less constant: in 42.3% of the nuclei both segments are associated with the nucleolus, in 39% of the nuclei only one heterochromatic segment presents such an association, and in 18.7% neither of the two heterochromatic segments is in nucleolar association. In 6% of the cells, one or two chromosome 9 heterochromatic segments are in contact with the nuclear membrane.

In situ hybridization using tritium-labeled 28S and 18S RNA shows that in the interphase nucleus the acrocentric short arms, carriers of ribosomal cistrons, are associated with the nucleolus.

These observations demonstrate the complexity of the nucleolus-associated chromatin which, in addition to segments of chromosomes 1, 9, 13, 14, 15, 21 and 22, may include the Y chromosome. They also confirm that the nucleolus constitutes one of the orientation points determining the relative localization of chromosomes in the interphase nucleus.

Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • A. Stahl
    • 1
  • M. Hartung
    • 1
  • A. M. Vagner-Capodano
    • 1
  • C. Fouet
    • 1
  1. 1.Laboratoire d'Histologie et Embryologie IIFaculté de MédecineMarseile Cedex 4France