Figure 1

Larval da neurons and timeline of dendritic remodeling during metamorphosis. (A) A lateral view of a third instar larva that highlights a large subset of dendritic arborization (da) neurons. Bipolar dendrites of dorsal bd (dbd) neurons are marked with blue arrows in this and subsequent figures. Genotype: UAS-mCD8::GFP/UAS-mCD8::GFP; C161 UAS-mCD8::GFP/TM3 Ser Sb. Anterior is to the left, and dorsal is at the top throughout this study. (B) A diagram of positions of multidendritic (md) neurons in an abdominal hemisegment (A2 to A7) of the Drosophila larval peripheral nervous system. Diamonds represent individual da neurons, and triangles represent other types of md neurons. Of the other md types, names of two bipolar dendrite neurons (dbd and vbd) and dmd1 are indicated for simplicity. d, l, v', and v represent dorsal, lateral, ventral prime, and ventral clusters, respectively. Each class of the da neurons is differently colored. Black lines represent fascicles of axons that extend from the neuronal cell bodies. Adapted from [17] with permission from Wiley-Blackwell. (C-F) Timeline (C) and representative images (D-F) of dendritic remodeling during metamorphosis. (C) 0 hr after puparium formation (APF) indicates time of pupariation. (D-F) Images of class IV ddaC. The cell bodies are indicated by yellow arrows. (E) We visualized both ddaC and hemocytes and performed time-lapse recordings. Dendritic branches became detached from the cell body (arrow) and disappeared. During the pruning, the hemocytes migrated by generating prominent lamellipodia (see also Additional file 1). (F) ddaC that regenerated its dendritic arbor in the adult tergite. Genotype: (D) ppk-EGFP/ppk-EGFP, (E) UAS-EGFP; ppk-EGFP/pxn-Gal4, and (F) FRT19A/FRT19A; Gal4^109(2)80UAS-mCD8::GFP/+. Scale bars: 100 μm (A, D-F).