Sequential changes in genome-wide DNA methylation status during adipocyte differentiation.
DNA methylation is an epigenetic mark on the mammalian genome. There are numerous tissue-dependent and differentially methylated regions (T-DMRs) in the unique sequences distributed throughout the genome. To determine the epigenetic changes during adipocyte differentiation, we investigated the sequential changes in DNA methylation status of 3T3-L1 cells at the growing, confluent, postconfluent and mature adipocyte cell stages. Treatment of 3T3-L1 cells with 5-aza-2'-deoxycytidine inhibited differentiation in a stage-dependent manner, supporting the idea that formation of accurate DNA methylation profile, consisting of methylated and unmethylated T-DMRs, may be involved in differentiation. Analysis by methylation-sensitive quantitative real-time PCR of the 65 known T-DMRs which contain NotI sites detected 8 methylations that changed during differentiation, and the changes in the patterns of these methylations were diverse, confirming that the differentiation process involves epigenetic alteration at the T-DMRs. Intriguingly, the dynamics of the methylation change vary depending on the T-DMRs and differentiation stages. Restriction landmark genomic scanning detected 32 novel T-DMRs, demonstrating that differentiation of 3T3-L1 cells involves genome-wide epigenetic changes by temporal methylation/demethylation, in addition to maintenance of a static methylated/demethylated state, and both depend on differentiation stage.
Laboratory of Cellular Biochemistry, Department of Animal Resource Sciences/Veterinary Medical Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Hideki
H
Sakamoto
Yasushi
Y
Kogo
Jun
J
Ohgane
Naka
N
Hattori
Shintaro
S
Yagi
Satoshi
S
Tanaka
Kunio
K
Shiota
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology* / Q000502:physiology*; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics*; D002874:Chromosome Mapping / Q000379:methods*; D004247:DNA / Q000235:genetics*; D019175:DNA Methylation; D019143:Evolution, Molecular; D005786:Gene Expression Regulation / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D051379:Mice; D017422:Sequence Analysis, DNA
D004247:DNA