A new class of tissue-specifically methylated regions involving entire CpG islands in the mouse

Masako Suzuki, Shun Sato, Yoshikazu Arai, Takashi Shinohara, Satoshi Tanaka, John M. Greally, Naka Hattori, Kunio Shiota*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)


CpG islands, which have higher GC content and CpG frequencies compared to the genome as a whole, are generally believed to be unmethylated in tissues except at promoters of genes undergoing X chromosome inactivation or genomic imprinting. Recent studies, however, have shown that CpG islands at promoters of a number of genes contain tissue-dependent, differentially methylated regions (T-DMRs). In general, the tissue-specific methylation is restricted to a part of the promoter CpG island, with hypomethylation of the remaining sequence. In the current study, using comparison between Restriction Landmark Genomic Scanning (RLGS) and in silico RLGS, we identified ten sperm-specific unmethylated Not I sites, T-DMRs located in CpG islands that were hypomethylated in sperm but near-completely methylated in the kidney and brain. Unusually, these T-DMRs involve the whole CpG island at each of these loci. We characterized one of these genes, adenine nucleotide translocator 4 (Ant4), which is expressed in germ cells. Using a promoter assay, we demonstrated that expression of Ant4 gene is controlled by DNA methylation at the CpG island sequences within the promoter region. Ant4 and other sperm-specific hypomethylated loci represent a new class of CpG islands that become completely methylated in different cell lineages. T-DMRs at CpG islands are functionally important gene regulatory elements that may now be categorized into two classes: T-DMRs involving a subregion of the CpG island and those that occupy the whole CpG island.

Original languageEnglish
Pages (from-to)1305-1314
Number of pages10
JournalGenes to Cells
Issue number12
Publication statusPublished - 2007 Dec
Externally publishedYes

ASJC Scopus subject areas

  • Genetics
  • Cell Biology


Dive into the research topics of 'A new class of tissue-specifically methylated regions involving entire CpG islands in the mouse'. Together they form a unique fingerprint.

Cite this