rdgB knockdown in neurons reduced nocturnal sleep in Drosophila melanogaster

• Published in: Biochemical and biophysical research communications Vol. 643; pp. 24 - 29
• Main Authors: Kobayashi, Riho, Yamashita, Yuko, Suzuki, Hiroko, Hatori, Sena, Tomita, Jun, Kume, Kazuhiko
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05.02.2023
• Subjects: Animals; Drosophila - genetics; Drosophila melanogaster; Drosophila melanogaster - genetics; Drosophila Proteins - genetics; Mammals; Mushroom body; Phospholipid Transfer Proteins; Photoreceptor Cells; Protein Serine-Threonine Kinases; rdgB; Sleep; Sleep - genetics; rdgB; Sleep; Drosophila melanogaster; Mushroom body
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2022.12.043

Recent studies revealed behaviorally defined sleep is conserved across broad species from insect to human. For evolutional analysis, it is critical to determine how homologous genes regulate the homologous function among species. Drosophila melanogaster shares numerous sleep related genes with mammals including Sik3, salt-inducible kinase 3, whose mutation caused long sleep both in mouse and fruit fly. The Drosophila rdgB (retinal degeneration B) encodes a membrane-associated phosphatidylinositol transfer protein and its mutation caused light-induced degeneration of photoreceptor cells. rdgB mutation also impaired phototransduction and olfactory behavior, indicating rdgB is involved in the normal neural transmission. Mammalian rdgB homologue, Pitpnm2 (phosphatidylinositol transfer protein membrane-associated 2) was discovered as one of SNIPPs (sleep-need index phosphoproteins), suggesting its role in sleep. Here, we show that rdgB is involved in sleep regulation in Drosophila. Pan-neuronal and mushroom body (MB) specific rdgB knockdown decreased nocturnal sleep. MB neurons play a dominant role, since the rescue of rdgB expression only in MB neurons in pan-neuronal knockdown reversed the sleep reducing effect of rdgB knockdown. These results revealed the sleep-related function of rdgB in Drosophila which may be conserved across species. •rdgB RNAi in all neurons decreased sleep in Drosophila melanogaster.•Exclusion of mushroom body rescued sleep decrease by pan-neuronal rgdB RNAi.•rdgB RNAi specifically in mushroom body neurons decreased sleep during night.