Fig. 3 Zebrafish mutants of ASD genes display brain size phenotypes
(A) Whole-brain volume mapping pipeline (STAR Methods).
(B) Eight-region zebrafish brain atlas derived from Thyme et al. (2019) and Randlett et al. (2015).22,42
(C) Hierarchical clustering of regional brain volume measurements comparing mutant and background-matched wild-type fish. Each rectangle in the clustergram represents the signed -log10-transformed p values from linear mixed models (LMM) (red, increased in mutant; blue, decreased in mutant). Regions with significant volume differences by LMM (p < 0.05) are outlined in yellow. p-values for homozygous and heterozygous mutants are shown in Figure S3A. For raw volume quantifications by region for all fish, see Table S3.
(D) tERK-immunostained brains of dyrk1aa?77/?77dyrk1ab?8/?8 and wild-type larvae at 6 dpf. Note the decrease in forebrain volume in mutants (arrowheads). Dorsal views. FB, forebrain; OT, optic tectum; CB, cerebellum. Scale bar, 50 ?m.
(E) Regional brain volume differences in dyrk1aa?77/?77dyrk1ab?8/?8 (n = 18) and wild-type (n = 18) relative to the standard zebrafish reference brain 42 (dotted line). ????p < 0.0001, ???p < 0.001, ?p < 0.05 (one-way ANOVA).
(F) Voxel-wise Z score values representing brain volume differences in dyrk1aa?77/?77dyrk1ab?8/?8 versus background-matched wild-type larvae. Images shown from left to right represent sequential slices: axial views, top row, dorsal to ventral; sagittal views, bottom row, lateral to medial. Scale bar, Z score (red/yellow, increased in mutant; cyan/purple, decreased in mutant).
(G) Voxel-wise Z score values representing brain volume differences for the following lines: scn1lab?44/?44, chd8?5/?5, tbr1a?64/?64tbr1b?10/?10, kdm5ba?17/?17kdm5bb?14/?14, and cul3a?7/?7cul3b?20/+. Axial views, top row; sagittal views, bottom row. The horizontal green line in the sagittal view indicates the slice shown in the axial view. FB, forebrain; MHB, midbrain-hindbrain boundary. Scale bar, Z score (red/yellow, increased in mutant; cyan/purple, decreased in mutant). For the number of animals used in imaging experiments, see STAR Methods (average n = 23?26 per genotype in two to four independent clutches).
(H) Genotype-level p values for each brain region combined for all homozygous mutants and cul3a?7/?7cul3b?20/+, excluding dyrk1a, using Fisher?s method. Scale represents the -log10-transformed combined p value. The forebrain (telencephalon) shows the most significant difference in volume (p = 8.32 × 10?6, Fisher?s combined probability test).