Mateos-Langerak Julio, Cavalli Giacomo
Chromatin and Cell Biology Lab, Institute of Human Genetics, CNRS, 141, rue de la Cardonille, 34396 Montpellier, France.
Adv Genet. 2008;61:45-66. doi: 10.1016/S0065-2660(07)00002-8.
Genome regulation takes place at different hierarchically interconnected levels: the DNA sequence level, the chromatin level, and the three-dimensional (3D) organization of the nucleus. Polycomb group (PcG) proteins are silencers that regulate transcription at all these three levels. They are targeted to specific sequences in the genome, contributing to maintain cellular identity. Recent research reveals that PcG proteins may be important actors at the level of the nuclear 3D structure. Here, we discuss our current knowledge of how PcG proteins regulate transcription across the three mentioned levels, and in particular their possible role in regulation of remote genes. We suggest the possibility that PcG proteins establish 3D networks of chromatin contacts as a mechanism to orchestrate gene expression.
DNA序列水平、染色质水平以及细胞核的三维（3D）组织水平。多梳蛋白家族（PcG）蛋白是在所有这三个水平上调节转录的沉默因子。它们靶向基因组中的特定序列，有助于维持细胞特性。最近的研究表明，PcG蛋白可能是核三维结构水平上的重要作用因子。在这里，我们讨论了我们目前对PcG蛋白如何在上述三个水平上调节转录的认识，特别是它们在远程基因调控中的可能作用。我们提出PcG蛋白建立染色质接触的三维网络作为协调基因表达机制的可能性。
