Chromatin domain boundaries: defining the functional domains in genome

Abstract

Eukaryotic genome is packaged in the nucleus with the help of several proteins. While this packaging is needed to accom­modate the large genome within the nuclear volume it also has functional consequences. It is well known that enhancers can act over a long distance to regulate expression of genes, however, they do not act on inappropriate promoters in the genome. The elements that prevent such unwanted interactions are called the boundary elements. Boundaries are impor­tant for the proper packaging and define functionally independent regulatory domains in the genome. Such elements have now been identified from yeast to human. Although sequence comparison of such elements does not reveal any similarity, boundaries from one species can work in other species indicating a functional conservation. This also suggests a common underlying mechanism of the function of boundary elements. Recent genome sequence information and high throughput techniques have opened new avenues to understand the nature of boundary elements and the mechanism of their function.