HGF and hypothyroidism: In the present study, we found that deficiency of the HGF/Met signaling pathway increased the expression of E-cadherin in thyrocytes and hindered the detachment of thyrocytes from the first anterior follicle to elongate along the pharyngeal midline, further leading to highly adhesive thyroid morphology and hypothyroidism in hgfa/met-deficient zebrafish embryos.