Fig. 3

prdm1a, prdm3, and prdm16 genetically compensate for each other in zebrafish craniofacial development. (A–C) RNA was isolated from the heads of prdm3−/−, prdm16−/− or wildtype embryos at 48 hpf. RT-qPCR was performed for prdm3 (A), prdm16 (B) or prdm1a (C). 5–10 genotyped heads were pooled for RNA. (n ​= ​3 replicate experiments). (D) Dorsal and lateral views of in situ hybridization for prdm1a in prdm3 and prdm16 mutants at 24 hpf. (E–M) prdm1a+/-;prdm3+/−;prdm16+/- ​triple heterozygous fish were generated and intercrossed. Embryos were collected and stained at 4 dpf with Alcian blue. Shown are dissected and mounted viscerocranium and neurocranium tissues from different allelic combinatorial mutants indicated. Selected inserts (E’, I’-K’, M’) show high magnification images of the jaw joints. Double arrowhead indicates ectopic cartilage, black star indicates loss of posterior ceratobranchial arches, single short black arrowhead indicates abnormal jaw joint, single long black arrowhead indicates clefting in the ethmoid plate. Abbreviations: ceratobranchial arches (cbs), ceratohyal (ch), ethmoid plate (ep), eye (e), fin bud (fb), hatching gland (hg), Meckel’s cartilage (m), palatoquadrate (pq), posterior pharyngeal arches (ppa), trabeculae (tr). Scale bar, 100 ​μm *p ​≤ ​0.05, **p ​≤ ​0.005, Student’s t-test.