Fig. 1
Flamingo is required for the formation of the C4da topographic map. a The three C4da neurons (D, M and V) in one hemi-segment of Drosophila larvae project into VNC to form an activity-dependent topographic map. This topography depends on the relative levels of dTim9 in these three neurons. The activity inhibition of M neurons shifts their axon terminals ventrally by increasing dTrim9 expression. b Representative images of the dorsal-ventral view of single C4da terminals (green) and the C4da neuropil marked by ppk-tdTomato (red). WT, wild type; fmiE59,fmi null allele of mutation; OE Fmi, overexpress flamingo. c The statistic analysis of the TI of C4da axon terminals. Fmi null mutation causes the axon terminals of V neurons to project toward the dorsal side of VNC, resulting in the mixing of M terminals with V terminals. There is a significant difference in the projection of the V-terminals of the fmi mutation and the wild type V-terminals in VNC. Overexpress Fmi has no effects on the formation of topography. d Overexpress Fmi rescues the topographic defect in fmi mutant C4da neurons. The axon terminals of fmi mutatnt V neurons relocated to the ventral side of C4da neuropil by overexpressing Fmi on it. There is a significant difference in the projection of V-terminals of the fmi mutation and the fmi mutation + OE Fmi. D, ddaC; M, v’ada; V, vdaB. *P < 0.05; **P < 0.01; ***P < 0.001; Scale bar, 2 μm. Error bars indicate mean ± SEM. WT: D, n = 22; M, n = 18; V, n = 23; fmiE59: D, n = 27; M, n = 25; V, n = 23; OE Fmi: D, n = 23; M, n = 25; V, n = 20; fmiE59 + OE Fmi: D, n = 21; M,n = 29; V, n = 23