Fig. 6

Notch3 is sufficient to promote brain pericyte proliferation. (A,B) N3ICD-EGFP overexpression increased the number of pdgfrb⁺ brain pericytes at 72 hpf. (A) Non-transgenic control larvae. (B) Tg(hsp70I:N3ICD-EGFP) larva heat-shocked (HS) at 48 hpf. (C,D) N3ICD overexpression rescued the brain pericyte deficit phenotype in notch3^fh332 mutant larvae at 72 hpf. (C) notch3^fh332 homozygous larvae heat-shocked at 48 hpf. (D) notch3^fh332 homozygous larvae carrying the Tg(hsp70I:N3ICD-EGFP) transgene and heat shocked at 48 hpf. Arrowheads, pdgfrb⁺ brain pericytes. (E) Quantification of pdgfrb⁺ brain pericytes in control and N3ICD fish at 72 hpf (n=30 each). (F) Quantification of brain pericytes and percentage of EdU⁺ pericytes in control and N3ICD fish heat-shocked at 72 hpf and EdU pulsed at 78 hpf (n=25 each). (G) Quantification of brain pericytes at 72 hpf in control larvae, N3ICD larvae heat-shocked at 48 hpf, control larvae treated with 25 µM AG1295, and N3ICD larvae heat-shocked at 48 hpf immediately followed by AG1295 treatment (ne20 each). (H) Quantification of brain pericytes at 72 hpf in notch3^fh332 larvae heat shocked at 48 hpf (control group) and notch3^fh332;Tg(hsp70I: N3ICD-EGFP) larvae heat shocked at 48 hpf. Error bars represent s.d. ^*P<0.001 by Student’s two-tailed t-test. Scale bar: 200 μm.