Role of human ribosomal RNA (rRNA) promoter methylation and of methyl-CpG-binding protein MBD2 in the suppression of rRNA gene expression.

ABSTRACT: The methylation status of the CpG island located within the ribosomal RNA (rRNA) promoter in human hepatocellular carcinomas and pair-matched liver tissues was analyzed by bisulfite genomic sequencing. Significant hypomethylation of methyl-CpGs in the rRNA promoter was observed in the tumor samples compared with matching normal tissues, which was consistent with the relatively high level of rRNA synthesis in rapidly proliferating tumors. To study the effect of CpG methylation on RNA polymerase I (pol I)-transcribed rRNA genes, we constructed pHrD-IRES-Luc (human rRNA promoter-luciferase reporter). In this plasmid, Kozak sequence of the pGL3-basic vector was replaced by the internal ribosome entry site (IRES) of encephalomyocarditis viral genome to optimize pol I-driven reporter gene expres

SUBMITTER: Ghoshal K 

PROVIDER: S-EPMC2242730 | biostudies-literature | 2004 Feb

REPOSITORIES: biostudies-literature