Extent of chromatin spreading determined by roX RNA recruitment of MSL proteins
Extent of chromatin spreading determined by roX RNA recruitment of MSL proteins
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DOI：
10.1126/science.1076686
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发表时间：
2002-11-22
期刊：
影响因子：
56.9
通讯作者：
Meller, VH
中科院分区：
文献类型：
--
作者：
Park, Y;Kelley, RL;Meller, VH
非翻译的roX 1和roX 2 RNA是果蝇雄性特异性致死（MSL）复合物的组成部分，该复合物修饰组蛋白以上调雄性X染色体的转录。roX基因通常位于X染色体上，并且roX转基因可以误导剂量补偿机制，使其在其他染色体上局部扩散。在这里，我们。MSL蛋白丰度作为MSL复合物是否从常染色体roX转基因顺式扩散的决定因素。细胞核中表达的roX基因的数量与roX转基因的扩散呈负相关。我们提出了一个模型，其中MSL蛋白组装成活性复合物结合新生roX成绩单。当MSL蛋白/roX RNA比率高时，组装将是有效的，并且复合物可以在仍然束缚于DNA模板的同时完成。我们建议，这种本地生产的MSL复合物决定了扩散到侧翼染色质的程度。
The untranslated roX1 and roX2 RNAs are components of the Drosophila male-specific lethal (MSL) complex, which modifies histones to up-regulate transcription of the male X chromosome. roX genes are normally located on the X chromosome, and roX transgenes can misdirect the dosage compensation machinery to spread locally on other chromosomes. Here we de. ne MSL protein abundance as a determinant of whether the MSL complex will spread in cis from an autosomal roX transgene. The number of expressed roX genes in a nucleus was inversely correlated with spreading from roX transgenes. We suggest a model in which MSL proteins assemble into active complexes by binding nascent roX transcripts. When MSL protein/roX RNA ratios are high, assembly will be efficient, and complexes may be completed while still tethered to the DNA template. We propose that this local production of MSL complexes determines the extent of spreading into flanking chromatin.