Peroxisomal import is circadian in glia and regulates sleep and lipid metabolism.

Peroxisomes are critical organelles that detoxify wastes while also catabolizing and anabolizing lipids. How peroxisomes coordinate protein import and support metabolic functions across complex tissues and timescales remains poorly understood in vivo. Using the Drosophila brain, we discover a striking enrichment of peroxisomes in the neuronal soma and the cortex glia that enwrap them. Unexpectedly, import of peroxisomal proteins into cortex glia, but not neurons, dramatically oscillated across time and peaked in the early morning. Rhythmic peroxisomal import in cortex glia autonomously required the circadian clock and Peroxin 5 (Pex5; peroxisomal biogenesis factor 5 homolog), with endogenous Pex5 protein peaking in the morning. Notably, removing Pex5 in cortex glia severely reduced sleep while concomitantly causing aberrant lipid metabolism characterized by ectopic lipid droplets and increases across multiple lipid families. Thus, the circadian import of peroxisomal proteins via Pex5 in cortex glia is essential for lipid homeostasis and organismal behavior.