Figure 7. Acj6 instructs PN wiring through a cell-surface combinatorial code.

(A and B) Heatmap summarizing changes in the dendrite innervation pattern of adPN neuroblast clones to eleven glomeruli (columns). Dark red (ectopic innervation) and dark blue (loss of innervation) indicate either acj6 mutant phenotype itself or no rescue of acj6 mutant phenotype (p ≥ 0.05 comparing to acj6 mutant innervation extent, by Chi-squared test here and after). White indicates either the wild-type innervation pattern or complete rescue of acj6 mutant phenotype (p ≥ 0.05 comparing to wild-type innervation extent). Light red (partial ectopic innervation) and light blue (partial loss of innervation) indicate that the phenotypic rescue was significant (p < 0.05 comparing to acj6 mutant innervation extent) but still different from wild-type (p < 0.05 comparing to wild-type innervation extent). Letters within the grids indicate panels where detailed quantifications are shown. Dots highlight an example of between-glomeruli additive interaction.

(C–G) Examples of additive (C and D), subtractive (E), and synergistic (F and G) interactions between Acj6-regulated cell-surface proteins.

(H) Summary of the cell-surface wiring executors of Acj6 for instructing correct targeting or preventing ectopic targeting of adPN dendrites to distinct glomeruli.

(I) Wiring specificity of different neuron types is dictated by a cell-surface protein combinatorial code, which is controlled by combinatorial expression of transcription factors—each transcription factor regulates the expression of multiple cell-surface proteins (divergence), and each cell-surface protein is regulated by multiple transcription factors (convergence).

See also Figures S7.