Related Experiment Video
Updated: Aug 13, 2026

In Vitro Bioluminescence Assay to Characterize Circadian Rhythm in Mammary Epithelial Cells
Published on: September 28, 2017
Wild-type circadian rhythmicity is dependent on closely spaced E boxes in the Drosophila timeless promoter
M J McDonald1, M Rosbash, P Emery
1Department of Biology, National Science Foundation Center for Biological Timing, Waltham, Massachusetts 02454, USA.
Abstract:
Transcriptional regulation plays an important role in Drosophila melanogaster circadian rhythms. The period promoter has been well studied, but the timeless promoter has not been analyzed in detail. Mutagenesis of the canonical E box in the timeless promoter reduces but does not eliminate timeless mRNA cycling or locomotor activity rhythms. This is because there are at least two other cis-acting elements close to the canonical E box, which can also be transactivated by the circadian transcription factor dCLOCK. These E-box-like sequences cooperate with the canonical E-box element to promote high-amplitude transcription, which is necessary for wild-type rhythmicity.
Related Concept Videos
Position-effect Variegation
The Eukaryotic Promoter Region
Circadian Rhythms and Gene Regulation
The Eukaryotic Promoter Region
Circadian Rhythms and Gene Regulation

