Analysis of the H19ICR Insulator

• DOI: 10.1128/mcb.02170-06
• Publication Date: 2007-03-06T01:28:43Z
• Authors: Young Soo Yoon; Sangkyun Jeong; Qi Rong; Kye-Yoon Park; Jae Hoon Chung; Karl Pfeifer
• Keywords: CTCF; Chromatin immunoprecipitation; Chromosome conformation capture; Imprinting (psychology)

Transcriptional insulators are specialized cis-acting elements that protect promoters from inappropriate activation by distal enhancers.The H19 imprinting control region (ICR) functions as a CTCF-dependent, methylation-sensitive transcriptional insulator.We analyzed several insertional mutations and demonstrate the ICR can function methylation-regulated maternal chromosome-specific insulator in novel chromosomal contexts.We used chromosome conformation capture chromatin immunoprecipitation assays to investigate configuration of at these insertion sites.By comparing paternal organizations on wild-type mutant chromosomes, we hoped identify mechanisms for function.We found promoter enhancer invariably associate form DNA loop domains transcriptionally active loci.Conversely, always prevent promoter-enhancer interactions.Instead, forms associating with blocked enhancers.We propose associations fundamental function.