Ca2+ signature gates responsiveness to exogenous auxin in Arabidopsis roots
Plants must continually balance growth with arrest, especially under stress. Auxin signaling acts as a central regulatory hub in this process, yet the mechanisms that dynamically tune auxin signaling in real time remain unknown. Here, we use the light-gated, Ca2+-permeable Channelrhodopsin 2 variant XXM2.0 to optogenet...