Abstract
Aurora kinases are serine/threonine protein kinases with essential roles in cell division through eukaryotes. Although functions of animal and yeast Aurora kinases have been analyzed in detail, those of plant Aurora kinases are unknown. Our live cell imaging analyses using cultured cells indicated that the plant Aurora kinase has dual roles; correction of aberrant kinetochore-microtubule attachment and dissociation of cohesin during chromosome alignment and segregation. We found three homologs and named AtAUR1, 2 and 3 in Arabidopsis thaliana.We also analyzed transgenic plants of Arabidopsis thaliana to express AtAUR3 with tdTomato. AtAUR3 localized around kinetochores of mitotic chromosomes in A. thaliana. We constructed the knockdown plant of AtAUR3. AtAUR3 knockdown induced the abnormality of root growth and leaf extension. An Aurora kinase inhibitor, Hesperadin, can inhibit the kinase activity of AtAUR3 and suppressed cell division in organs. These data suggest that the plant Aurora kinase plays a role in chromosome alignment and segregation in A. thaliana.
