SWI/SNF
Family members
Below is a list of yeast SWI/SNF family members and human orthologs:[4]
| yeast | human | function |
|---|---|---|
| SWI1 | ARID1A, ARID1B | contains LXXLL nuclear receptor binding motifs |
| SWI2/SNF2 | SMARCA4 | ATP dependent chromatin remodeling |
| SWI3 | SMARCC1, SMARCC2 | similar sequence, function unknown |
| SWP73 | SMARCD1, SMARCD2, SMARCD3 | similar sequence, function unknown |
| SWP61 | ACTL6A, ACTL6b | actin-like protein |
Mechanism of Action
Two mechanisms for nucleosome remodeling by SWI/SNF have been proposed.[5] 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.[6] A recent study[7] has provided strong evidence against the twist diffusion mechanism and has further strengthened the loop-recapture model, as proposed in the figure below.
See also
References
- ↑ Neigeborn L, Carlson M (1984). "Genes affecting the regulation of SUC2 gene expression by glucose repression in Saccharomyces cerevisiae". Genetics 108 (4): 845–58. PMID 6392017.
- ↑ Stern M, Jensen R, Herskowitz I (1984). "Five SWI genes are required for expression of the HO gene in yeast". J. Mol. Biol. 178 (4): 853–68. doi:10.1016/0022-2836(84)90315-2. PMID 6436497.
- ↑ Pazin MJ, Kadonaga JT (1997). "SWI2/SNF2 and related proteins: ATP-driven motors that disrupt protein-DNA interactions?". Cell 88 (6): 737–40. doi:doi:10.1016/S0092-8674(00)81918-2. PMID 9118215.
- ↑ Collingwood TN, Urnov FD, Wolffe AP (1999). "Nuclear receptors: coactivators, corepressors and chromatin remodeling in the control of transcription". J. Mol. Endocrinol. 23 (3): 255–75. doi:10.1677/jme.0.0230255. PMID 10601972.
- ↑ van Holde K, Yager T (2003). "Models for chromatin remodeling: a critical comparison". Biochem. Cell Biol. 81 (3): 169–72. doi:10.1139/o03-038. PMID 12897850.
- ↑ Flaus A, Owen-Hughes T (2003). "Mechanisms for nucleosome mobilization". Biopolymers 68 (4): 563–78. doi:10.1002/bip.10323. PMID 12666181.
- ↑ 7.0 7.1 Zofall M, Persinger J, Kassabov SR, Bartholomew B (2006). "Chromatin remodeling by ISW2 and SWI/SNF requires DNA translocation inside the nucleosome". Nat. Struct. Mol. Biol. 13 (4): 339–46. doi:10.1038/nsmb1071. PMID 16518397.
Transcription coregulators | |
|---|---|
| Coactivators | CARM1 - CRTC1 - CBP - NCOA1 (SRC-1) - NCOA2 (GRIP1/SRC-2/TIF2) - NCOA3 (AIB/SRC-3/TRAM-1) - NCOA4 - NCOA6 - NCOA7 - PPARGC1A - PPARGC1B - TGFB1I1 |
| Corepressors | NCOR1 - NRIP1 - NCOR2 (SMRT) - PELP-1 - RCOR1 - Rb - SIN3A- SIN3B - Tripartite motif-containing (TRIM24, TRIM28) |
| ATP-dependent remodeling factors | Chromatin Structure Remodeling (RSC) Complex - SWI/SNF |
Table of Contents In Alphabetical Order | By Individual Diseases | Signs and Symptoms | Physical Examination | Lab Tests | Drugs
Editor Tools Become an Editor | Editors Help Menu | Create a Page | Edit a Page | Upload a Picture or File | Printable version | Permanent link | Maintain Pages | What Pages Link HereThere is no pharmaceutical or device industry support for this site and we need your viewer supported Donations | Editorial Board | Governance | Licensing | Disclaimers | Avoid Plagiarism | Policies
