ABA mediated drought-accelerated flowering ($) (Mol Plant)

One of the most plastic developmental process in plants is the timing of flower initiation. Plants select favourable conditions to achieve reproductive success. Light and temperature are continuously monitored through molecular mechanisms that are still poorly understood. Drought escape (DE) is an adaptive mechanism which involves rapid flowering to enable the completion of the full life-cycle and seed set in spite of a drought event. In a new paper, Hwang et al. describe a class of abscisic acid (ABA)-related bZIP transcription factors, ABRE-BINDING FACTORS (ABFs), as key drivers for DE. In particular ABA signals are integrated by ABF3/4 into the floral network with the consequent transcriptional activation of SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1). At the same time, the photoperiodic pathway is also important for DE: ABA modulates GIGANTEA (GI) signaling and consequently its ability to activate the florigen genes. Take home message: ABA signaling provides different developmental information that allows plants to coordinate the balance between the vegetative and the reproduction phases, according to the available water resources. (Summarized by Francesca Resentini) Molecular Plant 10.1016/j.molp.2019.01.002 See also the Spotlight by Conti 10.1016/j.molp.2019.02.002