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Fig. 1
Alterations to movement influence craniofacial skeleton development. A) Flaccid paralysis leads to subluxation of the jaw joint. Brightfield (left hand panels) and Fluorescent images (right hand panels) of lateral views of the head (positioned anterior to left) of 5 day old zebrafish treated with DMSO (top) or MS222 to induce flaccid paralysis (lower panels). Note jaw ‘hanging open’ in MS222 treated larvae due to ‘subluxation’ of the jaw joint. B) Graph showing number of movements per minute in 72, 96 and 120 hours post fertilisation (hpf) sibling and vhl mutant larvae (n = 4,4,8,9,6,8). Statistical test is a 2 tailed Student t test. C) 5dpf craniofacial muscle. A41025 pan-skeletal muscle antibody stain of craniofacial muscle in 5dpf control, myod mutant, 3-5dpf MS222 anaesthetic treated DMB treated and vhl mutant zebrafish. White arrows mark the muscle fibres of the PH. IA, intermandibularis anterior; PH, protractor hyoideus; AM, adductor mandibularis; HI, hyoideus inferior; HS, hyoideus superior; SH, sternohyoideus. D) Muscle paralysis and hyperactivity affect cartilage jaw morphology. Confocal images, oriented anterior to top, of 5dpf cartilage elements of the lower jaw. 5dpf control, myod mutant, 3-5dpf MS222 anaesthetised treated and vhl mutant zebrafish cartilage elements were labelled with Collagen II antibody and DMB treated zebrafish cartilage were visualised using the Tg(Col2a1aBAC:mcherry) transgenic line. MC = Meckel's cartilage, PQ = palatoquadrate, CH = ceratohyal A, anterior; P, posterior; M, medial; L, lateral. (white boxes show regions for which further images are shown in Fig. 2 and Fig. 4).