DISTRIBUTION OF HISTONE H4 TRIMETHYLATED ON LYSIN-20 (H4K20me3) IN THE NEURONS OF THE RAT CEREBELLAR CORTEX

DOI: https://doi.org/10.29296/24999490-2018-03-10

I.M. Pleshakova(1, 2), D.A. Sufieva(1), D.E. Korzhevskii(1)
1-Institute of Experimental Medicine, Akademika Pavlova str., 12, Saint-Petersburg, Russian Federation, 197376;
2-Peter the Great St.Petersburg Polytechnic University, Polytechnicheskaya str., 29, Saint-Petersburg, Russian Federation, 194021
E-mail: Laylay.96@mail.ru

Introduction. Changes in the structural organization of the cell nucleus often precede the degeneration of the nerve cell. Histone H4 trimethylated on lysine 20 (H4K20me3) may act as one of the markers of neurodegenerative processes. The aim of this paper was to study the distribution of H4K20me3, which marks repressed genes within heterochromatin, in cerebellar cortex cells of intact rats. Methods. Cerebellar slices of mature male Wistar rats (n=8) were investigated by immunocytochemical method (rabbit polyclonal antibodies to H4K20me3 were used), light microscopy and confocal laser microscopy. Results. Purkinje cell nuclei were established to have a lot of H4K20me3 clusters distributed unevenly throughout the entire nucleus. Individual clusters are localized in the perinucleolar zone forming the large conglomerates. The nuclei of grain cells are characterized by an abundance of large heterochromatic globules (0,6–0,7 μm), which are immunopositive to H4K20me3. In the cytoplasm of neurons this protein was absent. Conclusion. In view of the presence of a few clearly identifiable heterochromatic structures in various nuclear compartments of Purkinje cells, one can expect that the detection of H4K20me3 redistribution in these neurons as a diagnostic method will be proved to be useful in determining the early stages of degeneration of these cells.
Keywords: 
histone H4 trimethylated on lysine 20, cerebellum, Purkinje cells, granul cells, immunohistochemistry, confocal laser microscopy.