Unravelling the role of DRIF transcription factors in Arabidopsis thaliana

Transcriptions factors play a pivotal role in the regulation of gene expression and in the control of several developmental processes. A new sub-family of transcriptional regulators, called DIV-and-RAD-interacting-factors (DRIFs) participate in an antagonistic module of interactions regulated by a small interfering peptide, and have been co-opted to regulate different developmental processes in plants. It is still unknown what molecular and cellular processes this module controls in Arabidopsis thaliana. Single knockout lines for five DRIF homologs do not show any obvious phenotypes, suggesting genetic redundancy. Double and triple mutants were obtained and are currently being analysed. One phenotype displayed by a triple mutant is late flowering under long days with no observable difference from wild-type plants under short days, suggesting that the DRIFs may be involved in the long-day flowering time pathway. The expression of genes controlling this pathway will be analysed in the triple mutant. Other phenotypes displayed by double and triple mutants are currently being explored and will be presented.