SUMMARY
The appearance of heterochromatin is generally accepted as a useful tool for the evaluation of the cell state including pathology; however, information on the heterochromatin DNA condensation state expressed by the image optical density in interphase nuclear regions and mitotic chromosomes with silent genes is very limited. Since human proliferating myeloblasts are a very convenient model, they were studied in the bone marrow of leukemic patients and established cell cultures using computer assisted image densitometry at the single cell level after heterochromatin visualization by a simple but sensitive cytochemical procedure for demonstration of DNA. As was expected, a high DNA image optical density was noted in central heterochromatin regions in contrast to the nuclear periphery at the nuclear envelope. Similarly, a high nuclear DNA image optical density was also expressed in mitotic chromosomes. Thus the possibility exists that the large heterochromatin DNA condensation expressed by the large image optical density in central nuclear regions, as in mitotic chromosomes, is related to silent gene locations. The similar width of mitotic chromosomes and chromatin fibrils in the heterochromatin regions in the interphase nuclei supports that explanation. The chromatin DNA fibrils in the central heterochromatin nuclear regions of interphase cells might just represent masked silent chromosomal segments. Such a conclusion is in harmony with “classical” cytology in the first part of the last century, which suggests the chromosome continuity from the mitotic division to the interphase where each chromatin region (“Kernbezirk”) actually represents a chromosomal territory.
KEY WORDS
heterochromatin image optical density; chromosomes; central nuclear regions; proliferating cells-human leukemic myeloblasts
REFERENCES
Arrighi F. Mammalian chromosomes. In Busch H (ed.): The Cell Nucleus 2. Academic Press, New York, 1974, pp. 1-33.
Bessis M. Living blood cells and their ultrastructure. Springer, Berlin, 1973.
Busch H, Smetana K. The Nucleolus. Academic Press, New York, 1970.
Cline MJ. The White Cell. Harvard University Press, Cambridge, 1975.
Cremer T, Cremer C. Rise, fall and resurrection of chromosome territories: a historical perspective. Part II. Fall and resurrection of chromosome territories during 1950s to 1980s. Part III. Chromosome territories and the functional nuclear architecture: experiments and models from 1980s to the present. Eur J Histochem. 50: 223-272, 2006.
[PubMed]
Fakan S. The functional architecture of the nucleus as analysed by ultrastructural cytochemistry, Histochem Cell Biol. 122: 83-93, 2004.
[CrossRef]
[PubMed]
Fakan S, Puvion E. The ulrastructural visualization of nuclear and nucleolar RNA synthesis and distribution. Int Rev Cytol. 65: 255-299, 1980.
[CrossRef]
Finlan IE, Sproul D, Thomson I, Boyle S, Kerr E, Perry P, Ylstra B, Chubb JR, Bickmore WA. Recruitment to the nuclear periphery can alter expression of genes in human cells. PLOS Genet. 4: e1000039, 2008.
[CrossRef]
[PubMed]
Frenster JH. Ultrastructure and function of heterochromatin and euchromatin. In Busch H (ed.): The Cell Nucleus 1. Academic Press, New York, 1974, pp. 565-581.
Grewal IS, Songtao J. Heterochromatin revisited. Nat Rev Gen. 8: 35-46, 2007.
[CrossRef]
[PubMed]
Grigoryev SA, Bulynko YA, Popova EY. The end adjusts the means: Heterochromatin remodeling during terminal cell differentiation. Chromosome Res. 14: 53-69, 2006.
[CrossRef]
[PubMed]
Hertwig G. Allgemeine mikroskopische Anatomie und Organisation der lebendigen Masse. In Mollendorf v W (ed.): Handbuch der Mikroskopischen Anatomie des Menschen, Die lebendige Masse1/1. Springer, Berlin, 1929, pp. 1-420.
Kumaran RI, Spector DL. A genetic locus targeted to nuclear periphery in living cells maintains its transcriptional competence. J Cell Biol. 180: 51-65, 2008.
[CrossRef]
[PubMed]
Pederson T. Chromatin structure and the cell cycle. Proc Natl Acad Sci USA. 69: 2224-2228, 1972.
[CrossRef]
Pederson T. The spatial organization of the genome in mammalian cells. Curr Opin Genet Dev. 14: 203-209, 2004.
[CrossRef]
Pikaard C, Pontes O. Heterochromatin: condense or excise. Nat Cell Biol. 9: 19-20, 2007.
[CrossRef]
[PubMed]
Rundles RW. Chronic myelogeneous leukaemia. In Williams WJ, Beutler E, Erslev AJ, Lichtman MA (eds.): Hematology. McGraw Hill, New York, 1983, p. 196-214.
Smetana K, Lejnar J, Potmesil M. A note to the demonstration of DNA in nuclei of blood cells in smear preparations. Folia Haematol. 88: 305-317, 1967.
Smetana K, Klamova H, Jiraskova I, Hrkal Z. To the density and distribution of heterochromatin in differentiating, maturing and apoptotic cells represented by granulocytic, lymphocytic and erythrocytic precursors. Folia Biol (Praha). 54: 8-11, 2008.
Smetana K, Karban J, Trneny M. Heterochromatin condensation in central and peripheral nuclear regions of maturing lymphocytes in the peripheral blood of patients suffering from B chronic lymphocytic leukemia - a cytochemical study. Neoplasma. 58: 426-431, 2011a.
[CrossRef]
[PubMed]
Smetana K, Mikulenkova D, Klamova H. Heterochromatin density (condensation) during cell differentiation and maturation using the human granulocytic cell lineage of chronic myeloid leukaemia as a convenient model. Folia Biol (Praha). 57: 216-221, 2011b.
Wassermann F. Wachstum und Vermehrunug der lebendigen Masse. In Mollendorf v W (ed.): Handbuch der mikroskopischen Anatomie des Menschen, Die lebendige Masse1/2. Springer, Berlin, 1929, pp. 1-807.
Zhimulev IF, Beliaeva ES. Heterochromatin, gene position effect and gene silencing. Genetika. 39: 187-201, 2003.
[PubMed]
|
CITED
Liu ZL, Chen R, Liao NF, Li ZQ, Wang Y. Spectrum Analysis and Measurment Research on Visual Density of the National Standard Densitometer. Spectrosc Spectral Anal. 32: 3315-3318, 2012.
Liu ZL, Chen R, Liao NF, Li ZQ, Wang Y. Greatly enhanced visual density measurement level of the national standard densitometer. Acta Phys Sin. 61, Art No 230601, 2012.
|
