Characterization of DUF724 gene family in Arabidopsis thaliana.

Eighteen genes that encode the proteins with highly conserved Domain of Unknown Function 724 (DUF724) and Agenet domains were identified in plant taxa but not in animals and fungi. They are actively expressed in many different plant tissues, implying that they may play important roles in plants. Here we report the characterization of their structural organizations, expression patterns and protein-protein interactions. In Arabidopsis, the DUF724 genes were expressed in roots, leaves, shoot apical meristems, anthers and pollen grains. At least seven of the ten Arabidopsis DUF724 proteins (AtDuf1 to AtDuf10) were localized in nucleus. Three of them (AtDuf3, AtDuf5 and AtDuf7) may form homodimers or homopolymers, but did not interact with other members of the same family. Together with the significant similarity between DUF724 proteins and FMRP in the fundamental and characteristic molecular architecture, the results implies the DUF724 gene family may be involved in the polar growth of plant cells via transportation of RNAs.