Enhancer competition between H19 and Igf 2 does not mediate their imprinting

作者：Jennifer V. Schmidt, John M. Levorse, Shirley M. Tilghman · 发表于：Proceedings of the National Academy of Sciences · 年份：1999 · DOI：10.1073/pnas.96.17.9733 · 被引用次数：93 · 研究领域：Genetic Syndromes and Imprinting、Epigenetics and DNA Methylation、Genomic variations and chromosomal abnormalities

The linked H19 and Igf2 genes on mouse distal chromosome 7 are subject to genomic imprinting. Competition between the promoters of the genes for transcription from shared enhancers has been proposed as an explanation for the coordinate expression and reciprocal imprinting of these two genes. To test this model, we have used Cre-loxP technology to generate in mice a conditional deletion of the H19 promoter and structural gene that leaves no transcription unit in the locus. Contrary to the prediction of enhancer competition we find that transcriptional activity from the H19 promoter is not required for the imprinted silencing of the Igf2 gene.