- SWI/SNF
-dependent manner, though the exact nature of this structural change is unknown.
Family members
Below is a list of yeast SWI/SNF family members and human
ortholog s:cite journal | author = Collingwood TN, Urnov FD, Wolffe AP | title = Nuclear receptors: coactivators, corepressors and chromatin remodeling in the control of transcription | journal = J. Mol. Endocrinol. | volume = 23 | issue = 3 | pages = 255–75 | year = 1999 | pmid = 10601972 | doi = 10.1677/jme.0.0230255 | issn = ]Mechanism of Action
Two mechanisms for nucleosome remodeling by SWI/SNF have been proposed.cite journal | author = van Holde K, Yager T | title = Models for chromatin remodeling: a critical comparison | journal = Biochem. Cell Biol. | volume = 81 | issue = 3 | pages = 169–72 | year = 2003 | pmid = 12897850 | doi = 10.1139/o03-038 | issn = ] The first model contends that a unidirectional diffusion of a twist defect within the nucleosomal DNA results in a corkscrew-like propagation of DNA over the octamer surface that initiates at the DNA entry site of the
nucleosome . The other is known as the "bulge" or "loop-recapture" mechanism and it involves the dissociation of DNA at the edge of the nucleosome with reassociation of DNA inside the nucleosome, forming a DNA bulge on the octamer surface. The DNA loop would then propagate across the surface of the histone octamer in a wave-like manner, resulting in the repositioning of DNA without changes in the total number of histone-DNA contacts.cite journal | author = Flaus A, Owen-Hughes T | title = Mechanisms for nucleosome mobilization | journal = Biopolymers | volume = 68 | issue = 4 | pages = 563–78 | year = 2003 | pmid = 12666181 | doi = 10.1002/bip.10323 | issn = ] A recent studycite journal | author = Zofall M, Persinger J, Kassabov SR, Bartholomew B | title = Chromatin remodeling by ISW2 and SWI/SNF requires DNA translocation inside the nucleosome | journal = Nat. Struct. Mol. Biol. | volume = 13 | issue = 4 | pages = 339–46 | year = 2006 | pmid = 16518397 | doi = 10.1038/nsmb1071 | issn = ] has provided strong evidence against the twist diffusion mechanism and has further strengthened the loop-recapture model, as proposed in the figure below.ee also
*
Chromatin Structure Remodeling (RSC) Complex
*Transcription coregulator References
External links
* [http://www.nextbio.com/b/home/home.nb?q=SWI%2FSNF%20complex&id=39051&type=biogroup&name=SWI%2FSNF%20complex&synonym=#cid=39051&tab=lit Nextbio]
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