DNA-histones

Chromatin The material of chromosomes. It is a complex of DNA, histones, and nonhistone proteins (chromosomal proteins, non-histone) found within the nucleus of a cell. [NIH]... 

Fig. 19. TLS analysis of the NCP, DNA, and histone core. In these ventral and dorsal views of the NCP model, the composite motion axes of the DNA, histones, and the NCP are shown in red, blue, and green, respectively. The center of motion axes for the DNA and the histones are non-coincident, the TLS axis for the DNA is furthest from the center of mass of the NCP. This may reflect the dominance of the DNA ends in the overall displacement of the DNA. The TLS analysis shows that DNA regions with high B-values, seen in Fig. 15, have little contribution to the overall motion of the DNA on the NCP. The overall motion of the NCP appears dominated by the DNA motion, with the TLS origin shifted in the direction and appearing congruent with the DNA. Overall, the primary axes of motion are in plane with the DNA, hence the interpretation that the composite motions are dominated by dynamic tension between the DNA and the histones, with deviation from these general motions the consequence of packing interactions.

Bazett-Jones, D.P., Cote, J., Landel, C.C., Peterson, C.L., and Workman, J.L. (1999a) The SWI/ SNF complex creates loop domains in DNA and polynucleosome arrays and can disrupt DNA-histone contacts within these domains. Mol. Cell. Biol. 19(2), 1470-1478. 

Salt bridges between positively charged basic amino acid side chains of histones and the negatively charged DNA phosphates play a major role in stabilizing the DNA-histone complex. Indeed, treatment of chromatin with concentrated NaCl (1-2 m), which is known to disrupt electrostatic bonds, causes a complete dissociation of DNA and histone in the nucleohistone complex. 

Eukaryotic DNA is replicated at a slower rate than prokaryotic DNA. One reason may be the requirement for the deposition of histone proteins on DNA (histone synthesis and DNA replication are coupled). Describe a model for the replication of eukaryotic DNA and nucleosome formation. 

Yoshikawa, Y., Nomura, S.M., Kanbe, T. and Yoshikawa, K. (2000) Controlling the folding/ unfolding transition of the DNA-histone HI complex by direct optical manipulation. Chem. Phys. Lett., 330, 77-82. 

In 1991, Luger et al. revealed by X-ray analysis the crystal structure of a natural DNA-histone complex. The X-ray structure shows in atomic detail how the histone protein octamer is assembled and how the base pairs of DNA are organized into a superhelix around it [74]. Since then this protein structure with cationic amino acids on the surface has acted as a model for the rational design of dendritic polymer-based gene vectors to mimic the globular shape of the natural histone complex [75-77]. 

B14. Bernstein, K. A., Valerio, R. D., and Lefkowith, J. B., Glomerular binding activity in MRL lpr serum consists of antibodies that bind to a DNA/histone/type IV collagen complex. J. Immunol. 154, 2424-2433 (1995). 

J2. Jacob, L., Viard, J. P., Allenet, B., Anin, M. F., Slama, F. B., etal., A monoclonal anti-double-stranded DNA autoantibody binds to a 94-kDa cell-surface protein on various cell types via nucleosomes or a DNA-histone complex. Proc. Natl. Acad. Sci. USA 86, 4669—4673 (1989). 

Suenaga, R., and Abdou, N. I., Anti-(DNA-histone) antibodies in active lupus nephritis. J. 

Ettig R, Kepper N, Stehr R et al (2011) Dissecting DNA-histone interactions in the nucleosome by molecular dynamics simulations of DNA unwrapping. Biophys J 101(8) 1999-2008... 

A4. Agnello, V., Arbetter, A., Ibanez, G., Powell, R., Tan, E. M., and Joslin, F., Evidence for a subset of rheumatoid factors that cross-react with DNA-histone and have a distinct cross idiotype. J. Exp. Med. 151, 1514-1527 (1980). 

Figure 1.6. DNA, histones, and cell division. Shown are (1) the structure of DNA, histones and genetic material (2) changes in genetic material via radiation or free radical induced damage and (3) the cell cycle, synthesis of DNA and mitosis.

Chromatin, is a complex of DNA, histones and other non-histone proteins. The chromosomes in the nucleus of eukaryotic cells exist as chromatin complexes. 

Vibrational spectroscopy was used to study native chromatin as well as reconstituted DNA-histone complexes. IR (Liquier et al., 1979) and Raman spectra (Goodwin and Brahms, 1978 Savoie et al., 1985) show that the DNA in chromatin adopts a B type conformation. The important role adopted by the a helical parts of the histones in stabilizing the B conformation of histone-DNA complexes was demonstrated by IR (Taillandier et al., 1984b). Raman spectra of chromatin have made it possible to localize histone-DNA interactions in the minor groove and non-histone protein-DNA interactions in the major groove (Goodwin and Brahms, 1978). 

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