Abstract
Mutations in eya1 cause branchio-oto-renal syndrome (BOR) in humans and the equivalent condition in animal models. BOR is characterized by multi-organ malformations. To better understand the role of Eya1 in organogenesis we used the zebrafish posterior lateral-line primordium. This multicellular tissue moves from head-to-tail at a constant velocity via the simultaneous action of two chemokine receptors, Cxcr4b and Ackr3b (formerly cxcr7b). We found that loss of eya1 strongly reduces the expression of ackr3b , disrupting the coherent motion of the primordium and leading to lateral-line truncations. These findings point to abnormal collective cell chemotaxis as the origin of organ dysmorphia in BOR.