Nucleosome binding

Brehm A, Langst G, Kehle J, Qapier CR, Imhof A, Eberharter A, Muller J, Becker PB (2000) dMi-2 and ISWl chromatin remodelling factors have distinct nucleosome binding and mobilization properties. Embo J 19 4332-4341... 

The Role of PARP-1 as a Specific Nucleosome-Binding Factor Effects on Chromatin Compaction and Chromatin-dependent Transcription... 

In addition to its role in the covalent modification of chromatin proteins, PARP-1 also functions as a nucleosome-binding protein and, hence, a structural component... 

How does PARP-Fs role as a nucleosome-binding protein and modulator of chromatin structure, which is evident under normal physiological conditions, impact PARP-1-dependent DNA repair, cell death, and inflammatory response pathways, which occur under pathophysiological conditions A number of different scenarios are possible. For example, PARP-l s chromatin-dependent activities may be critical for its function as a DNA repair protein, since the repair of genomic DNA must occur in the context of chromatin. In addition, nucleosome-stimulated autoPARylation may play a role in depleting cellular NAD+ pools in response to cellular stresses. Furthermore, PARP-Fs chromatin-dependent activities may help to regulate the expression of immune and inflammatory response genes. These possibilities will need to be examined in the future. 

PARP-1 is an abundant ( 1 to 2 million molecules per cell) and ubiquitous nuclear protein that plays important roles in a variety of cellular functions. One aspect of PARP-1 biology is the modulation of chromatin structure through direct nucleosome binding, covalent modification of chromatin proteins, or the production of PAR which can serve as a polyanionic matrix for the binding of chromatin proteins. Given its role in a variety of physiological and pathophysiological processes, PARP-1 has... 

Bergel M, Herrera JE, Thatcher BJ, Prymakowska-Bosak M, Vassilev A, Nakatani Y, Martin B, Bustin M (2000) Acetylation of novel sites in the nucleosomal binding domain of chromosomal protein HMG-14 by p300 alters its interaction with nucleosomes. J Biol Chem 275(15) 11514-11520... 

Formosa, T., Eriksson, P., Wittmeyer, J., Ginn, J., Yu, Y., and Stillman, D.J. (2001) Sptl6-Pob3 and the HMG protein Nhp6 combine to form the nucleosome-binding factor SPN. EMBO J. 20, 3506-3517. 

Nightingale, K., Dimitrov, S., Reeves, R., and Wolffe, A.P. (1996) Evidence for a shared structural role for HMGl and linker histones B4 and HI in organizing chromatin. EMBO J. 15, 548-561. Lichota, J. and Grasser, K.D. (2001) Differential association and nucleosome binding of the maize HMGA, HMGB, and SSRPl proteins. Biochemistry 40, 7860-7867. 

NLS Nucleosome-binding domain NLS Chromatin unfolding domain... 

HMGN proteins are small, ubiquitous, chromatin architectural elements that bind to the 147 bp nucleosome core via their highly conserved nucleosome binding domain. They bind as homodimers, interacting near base 25 of the nucleosome DNA, and near the dyad axis. When incorporated into minichromosomes, HMGN proteins decrease chromatin folding in a manner that is dependent on their C-terminal domain, with a concomitant increase in transcription. 

Brehm, A., Langst, G., Kehle, J., Clapier, C.R., Imhof, A., Eberharter, A., Muller, J., and Becker, P.B. (2000) dMi-2 and ISWI chromatin remodeling factors have distinct nucleosome binding and mobilization properties. EMBO J. 19, 4332-4341. 

Ramakrishnan, V., et al. (1993). Crystal structure of globular domain of histone H5 and its impUcations for nucleosome binding. Nature 362, 219-223. 

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