Chromatin Remodeling and Epigenetics

1)我们阐明了GagA因子结合位点周围特异性染色质重塑的机制。首先，Gaga因子将事实招募到其结合部位。然后，FACT诱导相邻核小体的构象变化，进而促进染色质的重塑。2)除了FACT外，我们还发现Brahma染色质重塑复合体的亚基是Gaga因子相关蛋白，表明Brahma复合体参与了Gaga因子-Fact复合体诱导的染色质重塑。3)遗传分析表明Gaga因子-Fact复合体有助于表观遗传维持HOX基因的表达。4)遗传学和生化分析表明Gaga因子-Fact复合体参与位置效应变异。5)我们利用RNAi在体内发现果蝇超卷曲因子在X染色体的剂量补偿中发挥关键作用。

1) We elucidated the mechanism underlying the site-specific chromatin remodeling around the GAGA factor-binding site. First, GAGA factor recruits FACT to its binding site. Then, FACT induces a conformational change in the neighboring nucleosomes, which in turn facilitates chromatin remodeling.2) We identified subunits of the Brahma chromatin remodeling compex as the GAGA factor-associated proteins besides FACT, suggesting that Brahma complex is involved in the GAGA factor-FACT complex induced chromatin remodeling.3) Genetic analysis revealed that the GAGA factor-FACT complex contributes to epigenetic maintenance of Hox gene expression.4) Genetic and biochemical analyses demonstrated that the GAGA factor-FACT complex is involved in position effect variegation.5) We found a crucial role of Drosophila supercoiling factor in the dosage compensation of X chromosome using RNAi in vivo.