Interaction between the GAGA factor and Mod(mdg4) proteins promotes insulator bypass in Drosophila.

ABSTRACT: Chromatin insulators or boundaries are proposed to structure the chromatin fiber into functionally independent domains by promoting the formation of chromatin loops. These elements can block the communication between an enhancer and a gene when placed between them. Interestingly, it has been previously observed that two tandem copies of the Drosophila Su(Hw) insulator abolish this enhancer-blocking activity, presumably through pairing. This bypass effect has not been described with other insulators, however. In this report, we show that the insertion of binding sites for the GAGA factor (GAF) between an enhancer and the Su(Hw) insulator allows bypassing of the insulator. This bypass relies on the activity of both the GAF protein and the Mod(mdg4)-67.2 protein, a factor required for Su(Hw)

SUBMITTER: Melnikova L 

PROVIDER: S-EPMC522021 | biostudies-literature | 2004 Oct

REPOSITORIES: biostudies-literature