The E3 ubiquitin ligase adaptor Tango10 links the core circadian clock to neuropeptide and behavioral rhythms

Abstract

Circadian transcriptional timekeepers in pacemaker neurons drive profound daily rhythms in sleep and wake. Here we reveal a molecular pathway that links core transcriptional oscillators to neuronal and behavioral rhythms. Using two independent genetic screens, we identified mutants of Transport and Golgi organization 10 (Tango10) with poor behavioral rhythmicity. Tango10 expression in pacemaker neurons expressing the neuropeptide PIGMENT-DISPERSING FACTOR (PDF) is required for robust rhythms. Loss of Tango10 results in elevated PDF accumulation in nerve terminals even in mutants lacking a functional core clock. TANGO10 protein itself is rhythmically expressed in PDF terminals. Mass spectrometry of TANGO10 complexes reveals interactions with the E3 ubiquitin ligase CULLIN 3 (CUL3). CUL3 depletion phenocopies Tango10 mutant effects on PDF even in the absence of the core clock gene timeless. Patch clamp electrophysiology in Tango10 mutant neurons demonstrates elevated spontaneous firing potentially due to reduced voltage-gated Shaker-like potassium currents. We propose that Tango10/Cul3 transduces molecular oscillations from the core clock to neuropeptide release important for behavioral rhythms.

Nonlinear expression patterns and multiple shifts in gene network interactions underlie robust phenotypic change in Drosophila melanogaster selected for night sleep duration

“…The genes we identify herein overlap and extend previous work. Of the 1,140 genes implicated in the generalized linear model, 151 (13.2%) overlapped with previous candidate gene, random mutagenesis, gene expression, and genome-wide association studies of sleep and circadian behavior in flies ( Harbison et al, 2009, 2013, 2017, 2019; Thimgan et al, 2010, 2018; He et al, 2013; Mallon et al, 2014; Dissel et al, 2015; Seugnet et al, 2017; Feng et al, 2018; Shalaby et al, 2018; Wu et al, 2018; Roessingh et al, 2019; Khoury et al, 2020; Lee et al, 2021; Pegoraro et al, 2022 ). Notably, previous studies identified the genes CG17574, cry, dro, mip120, Mtk, NPFR1, pdgy, PGRP-LC, Shal , and vari as affecting sleep duration ( Harbison et al, 2013; He et al, 2013; Mallon et al, 2014; Dissel et al, 2015; Feng et al, 2018; Thimgan et al, 2018; Khoury et al, 2020; Pegoraro et al, 2022 ).…”

“…The distribution of gene ratios for 1, 000 unrelated genes is plotted in the background. Genes having the most extreme ratios are indicated; see Table S14 , 2014;Dissel et al, 2015;Seugnet et al, 2017;Feng et al, 2018;Shalaby et al, 2018;Wu et al, 2018;Roessingh et al, 2019;Khoury et al, 2020;Lee et al, 2021;Pegoraro et al, 2022). Notably, previous studies identified the genes CG17574, cry, dro, mip120, Mtk, NPFR1, pdgy, PGRP-LC, Shal, and vari as affecting sleep duration (Harbison et al, 2013;He et al, 2013;Mallon et al, 2014;Dissel et al, 2015;Feng et al, 2018;Thimgan et al, 2018;Khoury et al, 2020;Pegoraro et al, 2022).…”

The circadian clock regulates PIF3 protein stability in parallel to red light

“…In plants, the core circadian clock is composed of transcriptional feedback loops, but 24-hour rhythmicity requires post-translational modification of transcription factors and eventually regulated degradation by the ubiquitin proteasome ( 1–3 ). The transcription factors that make up the core of the plant circadian clock also control the timing of output processes through direct regulation of gene transcription, but evidence suggests that there are rich hierarchical post-transcriptional and post-translational networks that tether the clock to outputs to ensure their 24-hour rhythmicity ( 4, 5 ). Efforts have led to increased understanding of the transcriptional connections between the circadian clock and its outputs, but we know far less about the post-translational connections, including degradation mechanisms that impart 24-hour rhythms on proteins that participate in these output processes.…”

Mutation of the Drosophila melanogaster serotonin transporter dSERT impacts sleep, courtship, and feeding behaviors

“…Furthermore, of the five serotonin receptors expressed in D. melanogaster, mutations in three (d5-HT1A, d5-HT2B and d5-HT7) disrupt sleep behaviors, including total sleep amount, sleep rebound, and/or sleep architecture [18,20,22]. The powerful molecular genetic tools available in the fly have allowed some of the structures and cells required for sleep to be identified [18,22,[25][26][27][28][29][30][31][32]. These tools have the potential to further dissect the mechanisms by which specific serotonergic circuits regulate sleep.…”