Anillin functions in distinct glial subtypes to support larval locomotion in Drosophila

Anillin (Ani)/Scraps has a well-characterized function in cytokinesis and has recently been shown to play a role in the nervous system. Ani is expressed in neuroblasts, axons, and neuromuscular junctions in the Drosophila larval nervous system, and pan-neuronal ani knockdown impairs both larval and adult behaviors. However, despite the expression of ani in glial cells, its function in these cells remains unclear. In the present study, we therefore investigated the role of ani in Drosophila glial cells by performing pan-glial ani knockdown and assessing the subsequent effects on larval and adult behaviors. Ani was expressed in a subset of glial cells, including in the central and peripheral nervous systems, and expression levels varied across individual cells. Pan-glial knockdown of ani significantly impaired larval and adult locomotion, larval learning ability, and adult activity; however, it did not affect lifespan. Although ani depletion decreased the number of glial cells in the central nervous system, it did not disrupt neuropil formation. In the peripheral nervous system, ani knockdown increased the total length of neuromuscular junctions. Subtype-specific knockdown analyses suggested that Ani functions in endoreplicating subperineurial and wrapping glia to support larval locomotion. The results also suggested a possible role for Ani in astrocyte-like and ensheathing glia, although the evidence is inconclusive. In contrast, Ani did not appear to have an obvious role in cortex glia or actively proliferating perineurial glia for larval locomotion. Together, these findings indicate that ani exerts both canonical and non-canonical roles in Drosophila glial cells.