The Drosophila Fab-7 chromosomal element conveys epigenetic inheritance during mitosis and meiosis
The Drosophila Fab-7 chromosomal element conveys epigenetic inheritance during mitosis and meiosis
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DOI：
10.1016/s0092-8674(00)81181-2
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发表时间：
1998-05-15
期刊：
影响因子：
64.5
通讯作者：
Paro, R
中科院分区：
文献类型：
--
作者：
Cavalli, G;Paro, R
多梳组（Polycomb group，PcG）和三胸组（trithorax group，trxG）基因产物负责维持包括同源异型基因在内的许多发育重要调控基因的抑制和活性表达模式。在果蝇胚胎中，Polycomb蛋白和trxG蛋白GAGA因子共定位于双胸复合物的Fab-7 DNA元件。在转基因株系中，Fab-7元件诱导侧翼GAL 4驱动的lacZ报告基因和迷你白基因的广泛沉默。然而，在胚胎发生期间GAL 4的短的单脉冲足以从转基因释放PcG依赖性沉默。Fab-7的这种激活状态是通过发育可遗传的，并且可以通过雌性减数分裂以GAL 4非依赖性方式传递给后代。因此，Fab-7是可转换的染色体元件，其可以传递表观遗传学确定的活性和抑制的染色质状态的记忆。
Polycomb group (PcG) and trithorax group (trxG) gene products are responsible for the maintenance of repressed and active expression patterns of many developmentally important regulatory genes including the homeotic genes. In Drosophila embryos, Polycomb protein and the trxG protein GAGA factor colocalize at the Fab-7 DNA element of the bithorax complex. In transgenic lines, the Fab-7 element induces extensive silencing on a flanking GAL4-driven lacZ reporter and mini-white genes. However, a short single pulse of GAL4 during embryogenesis is sufficient to release PcG-dependent silencing from the transgene. Such an activated state of Fab-7 is mitotically inheritable through development and can be transmitted in a GAL4-independent manner to the subsequent generations through female meiosis. Thus, Fab-7 is a switchable chromosomal element, which can convey memory of epigenetically determined active and repressed chromatin states.