Biopolymers and cell. 1993. Volume 9. № 5. 89 - 100

S. P. Shpilevaya, I. E. Kostetsky, K. M. Bilitch, L. I. Lihatcheva, T. V. Stolar, D. M. Irodov, E. V. Kostetskaya, I. M. Spivak, V. D. Zhestyanikov, V. A. Kordyum

The Interphase Chromatin Special State Zones

Summary

    The possibility is demonstrated of RecA protein of E. coll introduction into eukaryotic cell with preservation of its biologicall activity. The character of this protein affinity to chromatin of different degree of condensation is shown on cytological level (undirect immunofluorescent method combined with cytophotometry) for different stages of cellu¬lar cycle (protein is not tested in tneta- and anaphase chromosomes). The presence of bacterial RecA protein in the nuclei and cytoplasm of cells both in vitro and in vivo is confirmed with the help of immunoelectron microscopy. Studies were carried out on cultures of HeLa and Ltk~ cells and also in vivo on hepatocytes after direct injection on RecA protein and plasmid pKCR2 enclosed in liposomes into the liver of adult mice line BALB/c. Proceeding from the experimental data obtained and also considering the fact that RecA protein mainly connects with single-stranded DNA, the assumption is done about existence of special state chromatin zones (SSCZ). For these zones the active affinity to RecA protein serum is character with intensive fluorescence, thus they may correspond to some actively expressing genes, gathered in clusters.