Coupling neuropeptide levels to structural plasticity in Drosophila clock neurons

ANASTASIA HERRERO; TAISHI YOSHII; CARINA C. COLQUE; JAN A. VEENSTRA; NARA I MURARO; M FERNANDA CERIANI

CURRENT BIOLOGY

CELL PRESS

Lugar: United States; Año: 2020 p. 1 - 13

0960-9822

We have previously reported that Pigment dispersing factor (PDF) neurons, which areessential in the control of rest-activity cycles in Drosophila, undergo circadianremodeling of their axonal projections, a phenomenon called circadian structuralplasticity. Axonal arborizations display higher complexity during the day and becomesimpler at night, and this remodeling involves changes in the degree of connectivity.This phenomenon depends on the clock present within the ventrolateral neurons(LNvs) as well as in glia.In this work we characterize in detail the contribution of the PDF neuropeptide tostructural plasticity at different times across the day. Using diverse genetic strategies totemporally restrict its downregulation, we demonstrate that even subtle alterations toPDF cycling at the dorsal protocerebrum correlate with impaired remodeling,underscoring its relevance for the characteristic morning spread; PDF released fromthe small LNvs (sLNvs) and the large LNvs (lLNvs) contribute to the process.Moreover, forced depolarization recruits activity-dependent mechanisms to mediategrowth only at night, overcoming the restriction imposed by the clock on membraneexcitability. Interestingly, the active process of terminal remodeling requires PDFRsignaling acting locally through the cyclic nucleotide-gated channel CNGA. Thus,clock-dependent PDF signaling shapes the connectivity of these essential clockneurons on daily basis.