cfap298/Kurly Functions to Orient Centrosomes in the Early Zebrafish Embryo

Abstract

Polarized cell processes, such as those that allow for the coordinated movements of the cells in the embryo, are important for proper development. cfap298/c21orf59/Kurly is a protein previously identified for its role in maintaining polarization and proper function of motile cilia. However, kurly is expressed in cells that do not have motile cilia; we hypothesize that Kurly may affect other polarity events in these cells. In this study, we sought to determine how Kurly functions in polarized developmental events in contexts that are devoid of motile cilia. In cleavage stage kurly mutant embryos, we observe irregular cellular divisions and improper centrosome positioning and organization in kurly mutants, indicating that kurly affects polarization of centrosomes at these stages. These early defects did not affect embryo survivability: convergence and extension, a polarized gastrulation movement, was unaffected, and mutant embryos were able to sustain development to adulthood. To explore where Kurly protein functions at a subcellular level, various tools were designed and assessed in attempts to visualize kurly. Our results suggest that Kurly may function as a scaffold that recruits centrosomal organizing proteins to the centrosome and maintains other polarized developmental events.