title: Analysis of tissue-specific differentially methylated regions (TDMs) in humans.
abstract: Alterations in DNA methylation have been implicated in mammalian development. Hence, the identification of tissue-specific differentially methylated regions (TDMs) is indispensable for understanding its role. Using restriction landmark genomic scanning of six mouse tissues, 150 putative TDMs were identified and 14 were further analyzed. The DNA sequences of the 14 mouse TDMs are analyzed in this study. Six of the human homologous regions show TDMs to both mouse and human and genes in five of these regions have conserved tissue-specific expression: preferential expression in testis. A TDM, DDX4, is further analyzed in nine testis tissues. An increase in methylation of the promoter region is significantly associated with a marked reduction of the gene expression and defects in spermatogenesis, suggesting that hypomethylation of the DDX4 promoter region regulates DDX4 gene expression in spermatogenic cells. Our results indicate that some genomic regions with tissue-specific methylation and expression are conserved between mouse and human and suggest that DNA methylation may have an important role in regulating differentiation and tissue-/cell-specific gene expression of some genes.
authors.affiliation: Life Science, Advanced Research Institute for the Sciences and Humanities, Nihon University School of Medicine, Tokyo 173-8610, Japan.
authors.forename: Eiko
authors.initials: E
authors.lastname: Kitamura
authors.forename: Jun
authors.initials: J
authors.lastname: Igarashi
authors.forename: Aiko
authors.initials: A
authors.lastname: Morohashi
authors.forename: Naoko
authors.initials: N
authors.lastname: Hida
authors.forename: Toshinori
authors.initials: T
authors.lastname: Oinuma
authors.forename: Norimichi
authors.initials: N
authors.lastname: Nemoto
authors.forename: Fei
authors.initials: F
authors.lastname: Song
authors.forename: Srimoyee
authors.initials: S
authors.lastname: Ghosh
authors.forename: William A
authors.initials: WA
authors.lastname: Held
authors.forename: Chikako
authors.initials: C
authors.lastname: Yoshida-Noro
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nagase
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001483:Base Sequence; D018899:CpG Islands / Q000235:genetics; D053487:DEAD-box RNA Helicases / Q000235:genetics; D019175:DNA Methylation; D005786:Gene Expression Regulation; D015894:Genome, Human; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D009928:Organ Specificity; D013091:Spermatogenesis; D013737:Testis / Q000378:metabolism
chemical_list: C498288:DDX4 protein, human; C090864:Ddx4 protein, mouse; D053487:DEAD-box RNA Helicases