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Updated: Jul 7, 2026

Quantitative Comparison of cis-Regulatory Element (CRE) Activities in Transgenic Drosophila melanogaster
Published on: December 19, 2011
Independent effects of cis- and trans-regulatory variation on gene expression in Drosophila melanogaster
Patricia J Wittkopp1, Belinda K Haerum, Andrew G Clark
1Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA. wittkopp@umich.edu
Abstract:
Biochemical interactions between cis-regulatory DNA sequences and trans-regulatory gene products suggest that cis- and trans-acting polymorphisms may interact genetically. Here we present a strategy to test this hypothesis by comparing the relative cis-regulatory activity of two alleles in different genetic backgrounds. Of the eight genes surveyed in this study, five were affected by trans-acting variation that altered total transcript levels, two of which were also affected by differences in cis-regulation. The presence of trans-acting variation had no effect on relative cis-regulatory activity, showing that cis-regulatory polymorphisms can function independently of trans-regulatory variation. The frequency of such independent interactions on a genomic scale is yet to be determined.
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