RT Journal Article SR Electronic T1 DNA Methylation and Histone Modification Profiles of Mouse Organic Anion Transporting Polypeptides JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 72 OP 78 DO 10.1124/dmd.112.047969 VO 41 IS 1 A1 Satoki Imai A1 Ryota Kikuchi A1 Hiroyuki Kusuhara A1 Yuichi Sugiyama YR 2013 UL http://dmd.aspetjournals.org/content/41/1/72.abstract AB Organic anion transporting polypeptides (rodents, Oatps; human, OATPs) are primarily involved in the transmembrane transportation of a wide range of endogenous and exogenous compounds. Multiple mouse Oatp1 isoforms are closely located on chromosome 6, where each isoform shows distinct tissue distribution; Oatp1b2, Oatp1a6, and Oatp1c1 are expressed exclusively in the liver, kidney, and cerebrum, respectively; Oatp1a1 in the liver and kidney; and Oatp1a4 in the liver and cerebrum. We have identified tissue-dependent differentially methylated region (T-DMR) around the transcriptional start site (TSS) of Oatp1b2, which correlates with its liver-specific expression. Bisulfite sequencing also demonstrated the presence of T-DMRs around the TSS in other Oatp1 genes: CpG dinucleotides at +149 relative to the TSS for Oatp1c1; −48, +101, and +356 for Oatp1a4; −572 and −550 for Oatp1a1; and −122 and +216 for Oatp1a6 were differentially methylated among the liver, kidney, and cerebrum. These methylation profiles were largely consistent with the tissue distribution of Oatp1 mRNAs. Chromatin immunoprecipitation assay revealed that the mRNA expression of Oatp1 genes was accompanied by acetylated histone H3. Human OATP1B1 and OATP1B3 are located on chromosome 12p12 in the OATP1 cluster; both show predominant expression in the liver. These genes also contained T-DMRs that were hypomethylated in the liver, compared with kidney cortex: −511, −411, and +92 relative to the TSS for OATP1B1 and −331, +70, and +73 for OATP1B3. These results suggest that the difference in epigenetic profiles comprising DNA methylation and histone acetylation determines the distinct tissue distribution of Oatp/OATP mRNAs.