Toniolo D, Filippi M, Dono R, Lettieri T, Martini G
Istituto di Genetica Biochemica ed Evoluzionistica, CNR, 27100 Pavia, Italy.
Gene. 1991 Jun 30;102(2):197-203. doi: 10.1016/0378-1119(91)90078-p.
The nucleotide (nt) sequence of the entire CpG island in the 5' region of the human glucose-6-phosphate dehydrogenase-encoding gene (G6PD) and of the corresponding region in mouse was determined. In comparison to the human gene, the 5' region of the mouse G6PD gene has highly reduced G + C and CpG dinucleotide content, but maintains the functional features of a CpG island, as it is differentially methylated on the active vs. the inactive X chromosome. In addition to the expected conservation of exons, nt sequence comparison showed that several boxes are highly conserved between the two species in the 5' flanking DNA and in the first intron. Moreover, the conservation of the position of most CpG dinucleotides in the promoter region and in one of the upstream boxes, at about -900, gives support to the hypothesis that, in each island, specific CpGs play a major role in the regulation of gene expression.
测定了人类葡萄糖-6-磷酸脱氢酶编码基因（G6PD）5'区域整个CpG岛的核苷酸（nt）序列以及小鼠相应区域的序列。与人类基因相比，小鼠G6PD基因的5'区域G + C和CpG二核苷酸含量大幅降低，但仍保持CpG岛的功能特征，因为它在活性X染色体与失活X染色体上存在差异甲基化。除了外显子的预期保守性外，核苷酸序列比较表明，在5'侧翼DNA和第一个内含子中，两个物种之间有几个框高度保守。此外，启动子区域和约-900处的一个上游框中大多数CpG二核苷酸位置的保守性支持了这样一种假设，即在每个岛中，特定的CpG在基因表达调控中起主要作用。
