Fig. 1

plcβ3 mutants have defects in facial skeletal patterning. (A--C) Lateral views of live wild-type, plcβ3 homozygous, and plcβ3 heterozygous larvae at 6 dpf. plcβ3 homozygotes have an open-mouth phenotype and fail to form a swimbladder (white asterisk in panel A). (D--F) Flat mounts of wild-type, plcβ3 homozygous, and plcβ3 heterozygous larvae Alcian-green-stained mandibular and hyoid cartilages at 6 dpf. Homozygotes have fusions at the joint region between the palatoquadrate and Meckel's cartilage of the mandibular arch and strong reductions in the symplectic and ceratohyal cartilages of the hyoid arch. Meckel's cartilage is less severely reduced in length and the palatoquadrate is reduced and/or misshaped. Wild-type D/V joint regions are indicated with arrows in panel D. Fusions at joint regions in plcβ3 homozygotes are indicated with asterisk in panel E. Reductions in symplectic cartilage in plcβ3 heterozygotes are indicated with asterisk in panel F. Cartilages are labeled as followed: pq (palatoquadrate), mc (Meckel's cartilage), hm (hyomandibula), ch (ceratohyal), sy (symplectic), and ih (interhyal). Two bones of hyoid arch are also lightly stained with Alcian green: op (opercle), bsr_p (branchiostegal ray posterior). The opercle is frequently reduced or expanded in plcβ3 heterozygotes, while branchiostegal ray posterior is frequently absent. (G--I) Flatmounts of wild-type, plcβ3 homozygous, and plcβ3 heterozygous larvae doubly stained with Alcian blue and Alizarin red for cartilage and bone, respectively. In homozygotes ectopic cartilage nodules are frequently located near basihyal (bh) cartilage (asterisks in panel H). Ceratohyal cartilages are also +-frequently reduced to nubbins (arrowheads in panel H). Anterior ceratobranchials (cb) are typically reduced in length. Ceratobranchials are indicated with dots in panel G. In heterozygotes ectopic cartilage nodules frequently extend from the palatoquadrate cartilage (asterisk in panel I). Scale bars: 50 μm.