CDF3 orchestrates both flowering time and abiotic stress responses in Arabidopsis:

Abiotic stresses such as drought and extreme temperatures are among the major environmental factors that limit plant growth, development and productivity. Plants have developed sophisticated molecular, biochemical and physiological mechanisms to reduce consumption of resources and adjust their growth to environmental conditions. However, the molecular mechanisms that precisely modulate these responses remain poorly understood.

In this work, we identify Arabidopsis Cycling Dof Factor 3 (CDF3) as a key factor participating in abiotic stress responses and developmental processes like flowering time. We show that CDF3 overexpression enhances plant tolerance to drought, cold and osmotic stress, whereas down-regulation of CDF3 (cdf3-KO) leads to attenuated resistance. Moreover, CDF3 regulates a set of genes, both in GIGANTEA-dependent and -independent pathways, involved in cellular osmoprotection, ROS homeostasis, and nitrogen/carbon metabolism, which are associated with changes in sugar and amino acid levels in stressed plants. Our results provide new insights into the molecular mechanisms involved in partitioning of C/N rich compounds depending on age, stage of plant development and environmental cues; and their influence on plant growth and the control of flowering time. These findings are relevant for improving crop productivity and resource use efficiency under unfavorable environmental conditions.