Abstract
The NAC domain transcription factor is plant specific and forms a large family in Arabidopsis. To analyze the function of this family, we applied the chimeric repressor gene silencing technology (CRES-T system) and suppressed the expression of the NAC target genes. We show here that the two novel NAC genes, NAS1 and NAS2, are the regulator for anther dehiscence. Expression of the chimeric repressor of the NAC transcription factor driven by its own promoter resulted in undehiscent anther and male sterile. This defect was due to loss of secondary wall thickenings in anther endothecium. Analysis using the promoter-reporter genes showed that promoter activities of NAS1 and NAS2 were detected in anther wall. Ectopic expression of NAS1 and NAS2 induced ectopic secondary wall thickenings in various aboveground tissues. These suggest that NAS1 and NAS2 are involved to anther dehiscence by promoting secondary wall thickenings in anther wall.
