Fig. 5

Chromosomal deficiencies of CASK reveal dosage sensitivity of the bushy phenotype. For two deficiencies, 3 div larval CNS cultured neurons were compared among three genotypes: CASK homozygous mutant (Δ18/Δ18), CASK hemizygous mutant (∆18/Df), and control allele over deficiency (Ex33/Df). a-c Photomicrographs of representative neurons, immunostained for neuronal membrane marker, from near the median for each of three parameters: total neurite length, territory area and branch density. 60X magnification; scale bar = 20 μm. a Ex33/Df(3R)X313. b-c Both Δ18/Δ18 and Δ18/ Df(3R)X313 neurons show bushy neurite arbors. d-k CASK hemizygous mutant neurons are more severely affected on most parameters. Quantification of neurite-arbor morphology; box-plot distributions depicted as in Fig. 3. Significance levels: *, p < 0.05; ***, p < 0.0005; ****, p < 0.00005. d-g Ex33/Df(3R)X307 (n = 104; orange) compared with Δ18/∆18 (n = 106; magenta) and Δ18/ Df(3R)X307 (n = 106; green). h–k Ex33/Df(3R)X313 (n = 106; orange), compared with Δ18/∆18 (n = 105; magenta) and Δ18/ Df(3R)X313 (n = 106; green)