Fig. 3.

The cerebral hemorrhage and CtA angiogenic defects in dyrk1aa^krb1 mutants can be rescued by dyrk1aa expression, with the kinase activity of Dyrk1aa required for its phenotypic rescues. (A) The o-dianisidine staining images at 52 hpf showed that the cerebral hemorrhage (arrows) of dyrk1aa^krb1 embryos was rescued by WT dyrk1aa mRNA expression, but not in no-injection control, K193R-dyrk1aa or mCherryRed mRNA. (B) The frequency of cerebral hemorrhage of dyrk1aa^krb1 was reduced from 41.7% to 25.4% by injecting WT dyrk1aa mRNA of 0.1 ng, but not significantly changed by injecting K193R-dyrk1aa or mCherryRed mRNA at 52 hpf. (C) Injection of mRNAs of WT dyrk1aa, K193R-dyrk1aa or mCherryRed control did not affect the cerebral hemorrhage in WT embryos at 52 hpf. The mean percentages for each genotype were presented from three independent experiments with approximately 20 embryos in each repeat. (D) The compiled images of CtAs of Tg(kdrl:EGFP) at 52 hpf by confocal microscopy showed that the angiogenic defects of the CtAs of dyrk1aa^krb1 embryos were rescued by WT dyrk1aa mRNA injection. (E) The mean percentages of length and branching points of CtAs in dyrk1aa^krb1 mutants were rescued from 66.5% to 83.4% and from 61.2% to 108.3%, respectively, with 0.05 ng of dyrk1aa mRNA injection, relative to WT as 100%, and rescued to 89.9% and 122.0%, respectively, with 0.1 ng of dyrk1aa mRNA injection. Expression with 0.2 ng of dyrk1aa mRNA did not exhibit the rescue effect. Expression of dyrk1aa mRNA with the same doses in WT embryos also increased the length and branching points of CtAs in a dose-dependent manner (113.8% and 139.6% with 0.2 ng of dyrk1aa mRNA, respectively). *P<0.05, **P<0.01, ***P<0.005 (one-way ANOVA). n.s., not significant. Data are mean±s.e.m. Scale bar: 100 µm in A; 50 µm in D.