In contrast, DMAP1 protein is known to be a corepressor of transcription that stimulates universal and local DNA methylation.38 Knocking down DAMP1 in human cell lines caused hypomethylation of the tumor suppressor gene p16 that leads to cell growth arrest. In a similar manner, the knocked down DMAP1 triggered hypomethylation of DNA repair products with resulting elevated genomic instability.39 The lower expression level of DMAP1 that we observed in the colon tissue from HIV-infected patients may indicate a low level of DMAP1 activity.
The authors thank the entire participants in this study particularly the patients. The authors thank the Pyrosequencing Lab for Genomic and Epigenomic Research, Digestive Health Center, The Gene Expression Microarray Core, and Bioinformatics Core in Cincinnati Children's Hospital Medical Center.
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