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bioRxiv · 10.1101/2020.04.29.065037

Gap junction protein INNEXIN2 modulates the period of free-running rhythms in Drosophila melanogaster

Ramakrishnan, A.·Sheeba, V.
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Abstract

The circadian neuronal circuit of Drosophila melanogaster is made up of about 150 neurons, distributed bilaterally and distinguished into 7 clusters. Multiple lines of evidence suggest that coherent rhythms in behaviour are brought about when these clusters function as a network. Although chemical modes of communication amongst circadian neurons have been well-studied, there has been no report of communication via electrical synapses made up of gap junctions. Here, we report for the first time that gap junction proteins - Innexins play crucial roles in determining the period of free-running activity rhythms in flies. Our experiments reveal the presence of gap junction protein INNEXIN2 in the ventral lateral neurons. RNA-interference based knockdown of its expression in circadian pacemakers slows down the speed of locomotor activity rhythm. Concomitantly, we find alterations in the oscillation of a core-clock protein PERIOD and in the output molecule Pigment Dispersing Factor in the circadian pacemaker neuron network.

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Ramakrishnan, A., Sheeba, V.. 2020-04-30. Gap junction protein INNEXIN2 modulates the period of free-running rhythms in Drosophila melanogaster. https://doi.org/10.1101/2020.04.29.065037

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