Transcription factor required in several developmental processes (PubMed:19216761, PubMed:22216300, PubMed:25371059). Involved in axis formation during embryonic development by inhibiting tle3a/gro2 from binding to tcf7l1a, thereby facilitating ctnnb1-mediated transcription of canonical Wnt/CTNNB1 signaling target genes (PubMed:25371059). Regulates convergent extension movements and hypaxial myogenesis during gastrulation by activating non-canonical Wnt signaling via wnt5b (PubMed:19216761, PubMed:22406073). Required for the formation of myofibrils and fusion of fast muscle precursor cells, potentially via transcriptional regulation of genes specific to thick and thin myofilaments (PubMed:19216761). Regulates the migration of the posterior lateral line primordium during embryonic development, possibly via regulation of cxcl12a/sdf1a expression in the posterior lateral mesoderm, thereby modulating the deposition of neuromasts at correct intervals (PubMed:22216300). Interacts (via N-terminus) with tle3a/gro2 (via C-terminus). Expressed in the germ ring at the blastoderm margin during the shield stage and when embryo reaches 80% epiboly stage of gastrulation, expression is higher dorsally than ventrally (PubMed:19216761, PubMed:22406073). Expressed in the paraxial mesoderm, posterior lateral mesoderm and adaxial cells at the end of the bud stage (PubMed:19216761, PubMed:22216300). Expressed in the segmental plate and ventral mesoderm during early gastrulation and early somitogenesis (PubMed:25371059). Expressed at the posterior dorsal midline at the three-somite stage and extends to the anterior region along the notochord, and to the trunk somites and cells lateral to them in the 24 hours post-fertilization (hpf) (PubMed:22406073). Expressed in both dorsal and ventral fast muscle cells in the late stages of segmentation (PubMed:19216761). Expressed in the hindbrain, a subpopulation of spinal cord interneurons, hypaxial muscles and in migrating muscle cells giving rise to the hyoid muscles and pectoral fin muscles at 24 hpf (PubMed:25371059). Expressed in the neural tube and hindbrain at 36 and 48 hpf with additional expression in the pectoral fin bud and fin muscles at 48 hpf (PubMed:19216761, PubMed:22406073). Expression is lost from the trunk at 48 hpf (PubMed:19216761). Morpholino knockdown results in circling swimming behavior at the larval stage (PubMed:22216300). Reduced fin bud formation and loss of myod1 expression in embryo hyoid muscles (PubMed:19216761, PubMed:22216300, PubMed:22406073). Disruption of cuboidal morphology of adaxial cell pseudo-epithelium, and failure of myod1-expressing cells to incorporate into the adaxial cell layer (PubMed:19216761). Slow muscle fibers are abnormally shaped at 24 hpf and 48 hpf and fast muscle cells form shorter myofibrils at 24 hpf and 48 hpf, in addition unfused fast muscles cells are present at 48 hpf (PubMed:19216761). Reduced expression of thin filament genes in skeletal muscles and thick filament genes in embryos (PubMed:19216761). Weak and discontinuous pattern of cxcl12a/sdf1a expression just before the posterior lateral line (PLL) begins to migrate in the posterior lateral mesoderm at the tail bud stage, and in adaxial cells at the 10-somite stage (PubMed:22216300). Disruption of myoseptum distribution as a result of abnormal differentiation of cxcl12a/sdf1a-expressing cells in the horizontal myoseptum at 24 hpf (PubMed:22216300). Increase in cell death rate in the PLL primordium and deposited neuromasts at 36 hpf (PubMed:22216300). Decrease in the number of PLL neuromasts with 15% of morphants showing complete loss of neuromasts at 48 hpf (PubMed:22216300). The speed of PLL primordium migration is reduced and neuromasts are deposited at inappropriate locations along the length of the posteriorly extending primordium (PubMed:22216300). Disruption of the discrete dorsoventral domains resulting in narrowing of the mediolateral region and slower extension of the expression domains towards the dorsal region at the shield stage (PubMed:22406073). Abnormal anterior-posterior axis, reduced dorsalward movement speed of lateral marginal cells and reduced wnt5b expression at the end of gastrulation. Embryos have a broader neural plate in the neuroectoderm with shorter and broader notochords, and reduced cell elongation (PubMed:22406073).