CeBiTec Colloquium: 2009/03/02 Prof. Dr. Sabine Zachgo, Department of Botany, Biology, University of Osnabrück

2009/03/02, 17:15

CeBiTec Laboratory Building, Room G2-104

 

ROXYs: a novel function for plant glutaredoxins in flower development

Abstract:

Glutaredoxins (GRXs) have thus far been associated mainly with redox-regulated processes participating in stress responses. However, ROXY1, encoding a glutaredoxin, has recently been shown to regulate petal primorida initiation and further petal morphogenesis in Arabidopsis thaliana. ROXY1 belongs to a land plant-specific class of GRXs that has a CC-type active site motif, which deviates from ubiquitously occurring CPYC and CGFS GRXs. ROXY1 affects petal formation probably by catalysing the reduction of protein-protein disulphide bonds of its target proteins. To isolate these target proteins, Y2H screens were conducted, resulting in the identification of several TGA transcription factors. BiFC studies were conducted to address the question where these interactions occur intracellularly. Double mutant analysis confirms an interaction of ROXY1 with the floral TGA gene PERIANTHIA and point towards a dual function of ROXYs and TGAs during flower development.
Co-option of redox-sensitive networks during the evolution of more complex land plants into flower development as well as to stress responses will be discussed.