Belotserkovskaya R, Berger S L
Molecular Genetics Program, The Wistar Institute, Philadelphia, PA 19104, USA.
Crit Rev Eukaryot Gene Expr. 1999;9(3-4):221-30. doi: 10.1615/critreveukargeneexpr.v9.i3-4.70.
The question of a possible functional relationship between different chromatin-altering enzymatic activities is of great interest. Several remarkable parallels have been revealed regarding the action of the remodeling complex SWI/SNF and the histone acetylation complex SAGA during transcriptional activation in S. cerevisiae. Many promoters, but not all, that require one complex require the other as well. Mutations that disrupt both complexes cause much more severe phenotypes than single mutations. Both types of complexes are recruited to specific promoters by interaction with DNA-bound acidic activators, resulting in targeted acetylation and transcriptional activation. Taken together the data argue for independent mechanisms, but similar recruitment and functional interplay between these two types of chromatin-altering activities.
不同染色质改变酶活性之间可能存在的功能关系问题备受关注。关于重塑复合物SWI/SNF和组蛋白乙酰化复合物SAGA在酿酒酵母转录激活过程中的作用，已揭示出一些显著的相似之处。许多启动子（但并非全部）在需要一种复合物时也需要另一种复合物。破坏这两种复合物的突变所导致的表型比单个突变更为严重。这两种类型的复合物都是通过与结合DNA的酸性激活剂相互作用而被招募到特定启动子上，从而导致靶向乙酰化和转录激活。综合这些数据表明，这两种染色质改变活性之间存在独立的机制，但招募方式相似且存在功能相互作用。
