Bap55 acts postmitotically in PNs and dendrite mistargeting can be suppressed by human BAF53a and b. (A, B) Postmitotic expression of UAS-Bap55 can rescue the Bap55-/-dendrite mistargeting phenotype. The PN no longer targets to the anterior glomerulus DA4l (A1), but to the posterior glomerulus DL1 (A2). The L-shaped axon pattern is not altered (B). (C, D) In a small number of cases, postmitotic expression of UAS-Bap55 in a Bap55-/-single cell causes a de novo phenotype. The dendrites target to the anterior and medial glomerulus DM6 (C1), abandoning both DA4l (C1) and DL1 (C2). In these cases, it also causes a de novo axon phenotype of mistargeting ventrally to the lateral horn (white arrow in (D)). (E, F) Postmitotic expression of human UAS-Baf53a also rescues the Bap55-/-phenotype (E) and does not alter the L-shaped axon pattern (F). (G, H) Postmitotic expression of human UAS-Baf53b also rescues the Bap55-/-phenotype (G) and does not alter the L-shaped axon pattern (H). (I) Quantification of mistargeting phenotypes for (A, C, E, G). Green marks mCD8-GFP-labeled PNs generated by MARCM and labeled using GH146-GAL4. (A, C, E, G) show partial confocal stacks; (B, D, F, H) show full confocal stacks; magenta is the presynaptic marker nc82; symbols are as in Figure 2. Scale bars: 20 μm in (A) (for A, C, E, G) and (B) (for B, D, F, H).