Di Filippo Miriam, Bernardi Giorgio
Laboratory of Molecular Evolution, Stazione Zoologica Anton Dohrn, 80121 Naples, Italy.
Gene. 2008 Aug 1;419(1-2):62-5. doi: 10.1016/j.gene.2008.02.012. Epub 2008 Feb 21.
Mapping DNase-I hypersensitive sites (HS) was used in the past to identify regulatory elements of specific genes. More recently, thousands of HS were identified in the human genome by using high-throughput methods. These approaches showed a general enrichment of HS near or within known genes, within CpG islands, within human-mouse conserved regions and in GC-rich regions of the genome. Here we show that HS: (i) are characterized by a much higher GC level (approximately 56%) than the average GC level of the human genome (approximately 41%); (ii) are overwhelmingly located in the GC-richest compartment of the genome, which is predominantly associated with an open chromatin structure; (iii) and are slightly more and slightly less frequent than genes, respectively, in the gene-rich and in the gene-poor isochore families.
过去，绘制DNA酶I超敏位点（HS）被用于识别特定基因的调控元件。最近，通过高通量方法在人类基因组中鉴定出了数千个HS。这些方法表明，HS在已知基因附近或内部、CpG岛内、人鼠保守区域以及基因组的富含GC区域普遍富集。在这里，我们表明HS：（i）其GC水平（约56%）比人类基因组的平均GC水平（约41%）高得多；（ii）绝大多数位于基因组中GC含量最高的区域，该区域主要与开放染色质结构相关；（iii）在富含基因和基因贫乏的等密度区家族中，HS的频率分别略高于和略低于基因。
