Comparative expression of zebrafish lats1 and lats2 and their implication in gastrulation movements.

Large tumor suppressor (Lats) is a Ser/Thr kinase, and it presents an important function in tumor suppression. lats was originally identified in Drosophila and recently in mammals. In mammals, it contains two homologues, lats1 and lats2. In the present study, lats1 and lats2 were characterized from zebrafish (Danio rerio), which is the first report of lats in a nonmammalian vertebrate. The primary structure, genomic organization, and phylogenesis of lats from different species were studied, and the results suggest that lats1 is the direct descendant of invertebrate lats, whereas lats2 is formed by genome duplication. In zebrafish, both lats genes are maternally expressed, while they show distinctly different expression profiles during gastrulation. lats1 is almost ubiquitously expressed through development, and lats2 is more prominently expressed in the non-neural ectoderm region of zebrafish gastrula. Most intriguingly, as revealed by cell tracing and gene expression analysis, morpholino-mediated knockdown of either lats1 or lats2 led to obvious defects of cell migration in gastrulation, indicating the functional significance of lats in gastrulation movements.