Nucleosome disruption

Tsukiyama, T., Becker, P.B., Wu, C. (1994). ATP-dependent nucleosome disruption at a heat-shock promoter mediated by binding of GAGA transcription factor. Namre 367, 525-532. 

Fitzgerald DJ, Anderson JN (1999) Selective nucleosome disruption by drugs that bind in the minor groove of DNA. J Biol Chem 274(38) 27128-27138 Fox KR, Cons BM (1993) Interaction of mithramycin with DNA fragments complexed with nucleosome core particles comparison with distamycin and echinomycin. Biochemistry. 32(28) 7162—7171 Friedman HS, Kerby T, Calvert, H (2000) Temozolomide and treatment of malignant gliomas. CUn Cancer Res 6 2585-2597... 

Tsukiyama, T., Becker, P.B., and Wu, C. (1994) ATP-dependent nucleosome disruption at a heat-shock promoter mediated by binding of GAGA transcription factor. Nature 367, 525-532. Laurent, B.C., Yang, X., and Carlson, M. (1992) An essential Saccharomyces cerevisiae gene homologous to SNF2 encodes a helicase-related protein in a new family. Mol. Cell Biol. 12, 1893-1902. 

Morgan JE, Whitlock JP Jr. 1992. Transcription-dependent and transcription-independent nucleosome disruption induced by dioxin. Proc Natl Acad Sci USA 89 11622-11626. 

Chromatin remodeling, nucleosome remodeling, and nucleosome disruption are general terms that have been used to summarize a number of changes in chromatin structure. Often, these terms are used to define any event that alters the nuclease sensitivity of a region of chromatin, as nuclease sensitivity is a frequendy used marker of changes in chromatin structure. However, there have been other in vitro assays devised to... 

An enzyme activity ascribed to many coactivators, which transfers acetyl groups to lysine residues of histone tails of the nucleosomes and thereby facilitate their disruption and the opening of the chromatin. 

Figure 36-19. Supercoiling of DNA. A left-handed toroidal (solenoidal) supercoil, at left, will convert to a right-handed interwound supercoil, at right, when the cylindric core is removed. Such a transition is analogous to that which occurs when nucleosomes are disrupted by the high salt extraction of histones from chromatin.

Finally, the binding of specific transcription factors to cognate DNA elements may result in disruption of nucleosomal structure. Many eukaryotic genes have multiple protein-binding DNA elements. The serial binding of transcription factors to these elements—in a combinatorial fashion—may either directly disrupt the structure of the nucleosome or prevent its re-formation or recruit, via protein-protein interactions, multiprotein coactivator complexes that have the ability to covalently modify or remodel nucleosomes. These reactions result in chromatin-level structural changes that in the end increase DNA accessibifity to other factors and the transcription machinery. 

Tse C, Sera T, Wolffe AP, Hansen JC (1998) Disruption of higher-order folding by core histone acetylation dramatically enhances transcription of nucleosomal arrays by RNA polymerase III. Mol Cell Biol 18 4629 4 638... 

HIV-1 promoter and physically interacts with HAT complexes (Lee et at., 2002). Overexpression of a C/EBP dominant-negative inhibits disruption of the nucleosome nuc-1 (Lee et al, 2002). 

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