Fig 10

(A) Head expression of jag1b was quantified by RT-qPCR in full-sibling mef2ca mutant and wild-type embryos from low- and high-penetrance strains at 28 and 48 hpf. Expression of jag1b in mef2ca mutants was normalized to wild-type sibling expression levels (black line). Asterisks mark expression levels significantly different in mef2ca mutants compared with mef2ca wild types (T-test at alpha = 0.05), error bars are standard deviation. (B) Head expression of the Jag/N transcriptional targets hey1 and her6 was quantified by RT-qPCR in full-sibling jag1b mutant and wild-type embryos at 28 and 48 hpf. Expression of each target in jag1b mutants was normalized to wild-type sibling expression levels (black line). Asterisks mark genes with expression levels significantly different in jag1b mutants compared with jag1b wild types (T-test at alpha = 0.05). Error bars are standard deviation. (C) Head expression of the Jag/N transcriptional targets hey1 and her6 was quantified by RT-qPCR in full-sibling mef2ca mutant and wild-type embryos from low- and high-penetrance strains at 28 and 48 hpf. Expression of each gene in mef2ca mutants was normalized to wild-type sibling expression levels (black line). Asterisks mark genes with expression levels significantly different in mef2ca mutants compared with mef2ca wild types (T-test at alpha = 0.05). Error bars are standard deviation. (D) Spatial expression of her6 was determined by in situ hybridization. her6 is expressed in three discrete patches in pharyngeal arch 2 (arrows) in low-penetrance wild types, low-penetrance mutants and high-penetrance wild types. In only high-penetrance mef2ca mutants her6 expands ventrally (arrowhead). dlx2a expression was used to delineate pharyngeal arches one (a1) and two (a2) (dashed outlines). In the high penetrance strain, her6 was expanded in 0/7 homozygous wild types and 7/8 homozygous mutants. In the low-penetrance strain, her6 was expanded in 0/3 homozygous wild types and 0/5 homozygous mutants. Scale bar: 30 μm.