Abstract
The Arabidopsis transcriptional factor DREB2A plays important roles in response to water and heat stresses. The DREB2A protein is degraded under non-stressed condition by the ubiquitin-proteasome system, but under the water- and heat-stress conditions, the DREB2A protein accumulates in plant cells and induces the expression of downstream genes. The stability of DREB2A is regulated by the "negative regulatory domain (NRD)" composed of 30 amino acids, and the DREB2A protein lacking of NRD shows the constitutive stability and activity. However, details about the post-translational regulation of DREB2A have mostly yet to be revealed.
In this study, we identified a member of the NF-YC family as a novel interacting protein with DREB2A using yeast two-hybrid screening. Domain analysis revealed that the N-terminal region of DREB2A is sufficient for the protein-protein interaction. The interaction was confirmed in protoplasts prepared from Arabidopsis mesophyll cells by a bimolecular fluorescence complementation (BiFC) system. Now, we are analyzing the expression patterns of DREB2A downstream genes using over-expressing and knockout lines of the NF-YC gene.
