Orientation-dependent interaction between Drosophila insulators is a property of this class of regulatory elements.
Insulators are defined as a class of regulatory elements that delimit independent transcriptional domains within eukaryotic genomes. According to previous data, an interaction (pairing) between some Drosophila insulators can support distant activation of a promoter by an enhancer. Here, we have demonstrated that pairs of well-studied insulators such as scs-scs, scs'-scs', 1A2-1A2 and Wari-Wari support distant activation of the white promoter by the yeast GAL4 activator in an orientation-dependent manner. The same is true for the efficiency of the enhancer that stimulates white expression in the eyes. In all insulator pairs tested, stimulation of the white gene was stronger when insulators were inserted between the eye enhancer or GAL4 and the white promoter in opposite orientations relative to each other. As shown previously, Zw5, Su(Hw) and dCTCF proteins are required for the functioning of different insulators that do not interact with each other. Here, strong functional interactions have been revealed between DNA fragments containing binding sites for either Zw5 or Su(Hw) or dCTCF protein but not between heterologous binding sites [Zw5-Su(Hw), dCTCF-Su(Hw), or dCTCF-Zw5]. These results suggest that insulator proteins can support selective interactions between distant regulatory elements.
Kyrchanova
Olga
O
Department of the Control of Genetic Processes, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia.
Chetverina
Darya
D
Maksimenko
Oksana
O
Kullyev
Andrey
A
Georgiev
Pavel
P
D018528:ATP-Binding Cassette Transporters / Q000235:genetics; D000818:Animals; D001665:Binding Sites; D000076246:CCCTC-Binding Factor; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D005136:Eye Proteins / Q000235:genetics; D038101:Insulator Elements; D012097:Repressor Proteins / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation
D018528:ATP-Binding Cassette Transporters; D000076246:CCCTC-Binding Factor; C524946:CTCF protein, Drosophila; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005136:Eye Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C121540:dwg protein, Drosophila; C083738:su(Hw) protein, Drosophila; C059254:w protein, Drosophila