NUDC-LIKE GENES CONTRIBUTE TO ROOT GROWTH AND BRANCHING IN ARABIDOPSIS THALIANA

The Nuclear distribution C (NudC) domain-containing proteins play important roles in diverse cellular processes, including nuclear migration prior to asymmetric cell divisions, mitosis and cytokinesis. The function of plant NudC homologues remains largely unexplored. We investigated the effect of downregulation of two NudC genes, NMig1 and BOB1, focusing on their role in postembryonic development of the root system in Arabidopsis thaliana. Primary root growth and lateral root development were significantly inhibited in the nmig1 and bob1-3 mutants, when compared to the wild-type Col-0. Generation of transgenic plants with a beta-glucuronidase (GUS) reporter driven by the endogenous NMig1 promoter revealed expression of the gene in the primary root meristem. Strong GUS signal was also detected at all developmental stages of lateral root primordia. During the early stages, the NMig1 expression encompassed the entire root primordia, whereas at later developmental stages, the highest expression was detected in the central actively dividing cells forming the core of the primordia. These observations indicate that the NudC genes are involved in the initiation and development of the root system in Arabidopsis, and could be exploited as potential targets for breeding crops with an optimised root architecture.