Dopamine Receptor Interacting Protein 1 (DRIP1)

The isolation of Arabidopsis thaliana DRIP1 and DRIP2, C3HC4 RING domain-containing proteins that interact with the DREB2A protein in the nucleus. Overexpression of DRIP1 in Arabidopsis delayed the expression of DREB2A-regulated drought-responsive genes. Drought-inducible gene expression was slightly enhanced in the single T-DNA mutants of drip1-1 and drip2-1. By contrast, significantly enhanced gene expression was revealed in the drip1 drip2 double mutant under dehydration stress. Moreover, overexpression of full-length DREB2A protein was more stable in drip1-1 than in the wild-type background. DRIP1 and DRIP2 act as novel negative regulators in drought-responsive gene expression by targeting DREB2A to 26S proteasome proteolysis.