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In plants, sugars are the key source of energy and metabolic building blocks. The systemic transport of sugars is essential for plant growth and morphogenesis. Plants evolved intricate molecular networks to effectively distribute sugars. The dynamic distribution of these osmotically active compounds is a handy tool for regulating cell turgor pressure, an instructive force in developmental biology. In this study, we have investigated the molecular mechanism behind the dual role of the receptor-like kinase CANAR. We functionally characterized a long non-coding RNA, CARMA, as a negative regulator of CANAR. Sugar-responsive CARMA specifically fine-tunes CANAR expression in the phloem, the route of sugar transport. Our genetic, molecular, microscopy, and biophysical data suggest that the CARMA–CANAR module controls the shoot-to-root phloem transport of sugars, allows cells to flexibly adapt to the external osmolality by appropriate water uptake, and thus adjust the size of vascular cell types during organ growth and development. Our study identifies a nexus of plant vascular tissue formation with cell internal pressure monitoring, revealing a novel functional aspect of long non-coding RNAs in developmental biology. 

Abstract We present experimental and numerical investigations of high-energy mid-infrared filamentation with multi-octave-spanning supercontinuum generation (SCG), pumped by a 2.4 μm, 250 fs Cr:ZnSe chirped-pulse laser amplifier. The SCG is demonstrated in both anomalous and normal dispersion regimes with YAG and polycrystalline ZnSe, respectively. The formation of stable and robust single filaments along with the visible-to-mid-infrared SCG is obtained with a pump energy of up to 100 μJ in a 6-mm-long YAG medium. To the best of the authors’ knowledge, this is the highest-energy multi-octave-spanning SCG from a laser filament in a solid. On the other hand, the SCG and even-harmonic generation based on random quasi-phase matching (RQPM) are simultaneously observed from the single filaments in a 6-mm-long polycrystalline ZnSe medium with a pump energy of up to 15 μJ. The numerical simulations based on unidirectional pulse propagation equation and RQPM show excellent agreement with the measured multi-octave-spanning SCG and even-harmonic generation. They also reveal the temporal structure of mid-infrared filaments, such as soliton-like self-compression in YAG and pulse broadening in ZnSe.