Hydra vulgaris exhibits day-night variation in behavior and gene expression levels.

ABSTRACT:

Background

Day-night behavioral variation is observed in most organisms, and is generally controlled by circadian clocks and/or synchronization to environmental cues. Hydra species, which are freshwater cnidarians, are thought to lack the core clock genes that form transcription-translation feedback loops in clock systems. In this study, we examined whether hydras exhibit diel rhythms in terms of behavior and gene expression levels without typical clock genes.

Results

We found that the total behavior of hydras was elevated during the day and decreased at night under a 12-h light-dark cycle. Polyp contraction frequency, one component of behavior, exhibited a clear diel rhythm. However, neither total behavior nor polyp contraction frequency showed rhythmic changes under

SUBMITTER: Kanaya HJ 

PROVIDER: S-EPMC6407280 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature