Proteins chromosomal

The DNA in a eukaryotic cell nucleus during the interphase between cell divisions exists as a nucleoprotein complex called chromatin. The proteins of chromatin fall into two classes histones and nonhistone chromosomal proteins. 

The double-helical DNA is packaged into a more compact structure by a number of proteins, most notably the basic proteins called histones. This condensation may serve a regulatory role and certainly has a practical purpose. The DNA present within the nucleus of a cell, if simply extended, would be about 1 meter long. The chromosomal proteins compact this long strand of DNA so that it can be packaged into a nucleus with a volume of a few cubic micrometers. 

Abstract. In eukaryotic cells, replicated DNA molecules remain physically connected from their synthesis in S phase until they are separated during anaphase. This phenomenon, called sister chromatid cohesion, is essential for the temporal separation of DNA replication and mitosis and for the equal separation of the duplicated genome. Recent work has identified a number of chromosomal proteins required for cohesion. In this review we discuss how these proteins may connect sister chromatids and how they are removed from chromosomes to allow sister chromatid separation at the onset of anaphase. 

Orlando, V. (2000) Mapping chromosomal proteins in vivo by formaldehyde-crosslinked-chromatin immunoprecipitation. Trends Biochem. Sci. 3, 99-104. 

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]... 

Histones Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each. [NIH]... 

Bustin M (2001) Chromatin unfolding and activation by HMGN( ) chromosomal proteins. Trends... 

Ding HF, Bustin M, Hansen U (1997) Alleviation of histone Hl-mediated transcriptional repression and chromatin compaction by the acidic activation region in chromosomal protein HMG-14. Mol Cell Biol 17 5843-5855... 

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... 

Kramer OH, Baus D, Knauer SK, Stein S, Jager E, Stauber RH, Grez M, Pfitzner E, Heinzel T (2006) Acetylation of Stall modulates NF-kappaB activity. Genes Dev 20(4) 473 85 Kumar BR, Swaminathan V, Banerjee S, Kundu TK (2001) p300-mediated acetylation of human transcriptional coactivator PC4 is inhibited by phosphorylation. J Biol Chem 276(20) 16804-16809 Lim JH, West KL, Rubinstein Y, Bergel M, Postnikov YV, Bustin M (2005) Chromosomal protein HMGNl enhances the acetylation of lysine 14 in histone H3. EMBO J 24(17) 3038-3048 Li M, Luo J, Brooks CL, Gu W (2002) Acetylation of p53 inhibits its ubiquitination by Mdm2. J Biol Chem 277(52) 50607-50611... 

Lim JH, CatezF, Birger Y, West KL, Prymakowska-Bosak M, Postnikov YV, Bustin M (2004) Chromosomal protein HMGNl modulates histone H3 phosphorylation. Mol Cell 15(4) 573—584... 

HMGBl was first described as a non-histone chromosomal protein [1,80] and has been implicated in the maintenance and establishment of chromatin structure [10] as well as having more recently identified roles. 

Pil, P.M. and Lippard, S.J. (1992) Specific binding of chromosomal protein HMGl to DNA damaged by the anticancer drug cisplatin. Science 256, 234-237. 

Bustin, M. and Reeves, R. (1996) High mobility group chromosomal proteins architectural components that facilitate chromatin function. Progr. Nucl. Acid Res. Mol. Biol. 54, 35-100. 

Bustin, M. (1999) Regulation of DNA-dependent activities by the functional motifs of the high-mobility-group chromosomal proteins. Mol. Cell. Biol. 19, 5237-5246. 

Bustin, M. (2001) Revised nomenclature for high mobility group (HMG) chromosomal proteins. Trends Biochem. Sci. 26, 152-153. 

Costello, E., Saudan, P., Winocour, E., Pizer, L., and Beard, P. (1997) High mobility group chromosomal protein 1 binds to the adeno-associated virus replication protein (Rep) and promotes... 

Johns, E.W. (ed.) The HMG Chromosomal Proteins. Academic Press, New York. 

Jackson, J.B., Pollock, J.M., Jr., and Rill, R.L. (1979) Chromatin fractionation procedure that yields nucleosomes containing near-stoichiometric amounts of high mobility group nonhistone chromosomal proteins. Biochemistry 18, 3739-3748. 

Ronfani, L., Ferraguti, M., Croci, L., Ovitt, C.E., Scholer, H.R., Consalez, G.G., and Bianchi, M.E. (2001) Reduced fertility and spermatogenesis defects in mice lacking chromosomal protein Hmgb2. Development 128, 1265-1273. 

Nagaki, S., Yamamoto, M., Yumoto, Y., Shirakawa, H., Yoshida, M., and Teraoka, H. (1998) Non-histone chromosomal proteins HMGl and 2 enhance ligation reaction of DNA double-strand breaks. Biochem. Biophys. Res. Commun. 246, 137-141. 

Although chemically modifying DNA have distinctive implications for chromatin transitions and fiber structure in the presence of HI [250], in vivo these effects appear to work in concert with chromosomal proteins. 5 -Methylcytosines are specifically bound by members of the MBD (methyl-CpG-binding-domain) family, such as MeCP2 (Methyl-Cytosine binding Protein 2) and MBDl. These proteins have been shown to interact with HDACs and provide a casual link between DNA methylation, histone deacetylation and transcriptional repression [251-253]. 

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