PAD4, LSD1 and EDS1 regulate drought tolerance, plant biomass production, and cell wall properties

Abstract

Arabidopsis and poplar with modified PAD4, LSD1 and EDS1 genes exhibit successful growth under drought stress. The acclimatory strategies depend on cell division/cell death control and altered cell wall composition. The increase of plant tolerance towards environmental stresses would open much opportunity for successful plant cultivation in these areas that were previously considered as ineligible, e.g. in areas with poor irrigation. In this study, we performed functional analysis of proteins encoded by PHYTOALEXIN DEFICIENT 4 (PAD4), LESION SIMULATING DISEASE 1 (LSD1) and ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) genes to explain their role in drought tolerance and biomass production in two different species: Arabidopsis thaliana and Populus tremula × tremuloides. Arabidopsis mutants pad4-5, lsd1-1, eds1-1 and transgenic poplar lines PAD4-RNAi, LSD1-RNAi and ESD1-RNAi were examined in terms of different morphological and physiological parameters. Our experiments proved that Arabidopsis PAD4, LSD1 and EDS1 play an important role in survival under drought stress and regulate plant vegetative and generative growth. Biomass production and acclimatory strategies in poplar were also orchestrated via a genetic system of PAD4 and LSD1 which balanced the cell division and cell death processes. Furthermore, improved rate of cell division/cell differentiation and altered physical properties of poplar wood were the outcome of PAD4- and LSD1-dependent changes in cell wall structure and composition. Our results demonstrate that PAD4, LSD1 and EDS1 constitute a molecular hub, which integrates plant responses to water stress, vegetative biomass production and generative development. The applicable goal of our research was to generate transgenic plants with regulatory mechanism that perceives stress signals to optimize plant growth and biomass production in semi-stress field conditions.

The dual role of LESION SIMULATING DISEASE 1 as a condition‐dependent scaffold protein and transcription regulator

“…An exactly opposite pattern was demonstrated in LSD1-OE plants. These results are consistent with our recent study which was performed on two species, Arabidopsis and Populus tremula x tremuloides, demonstrating LSD1-dependent changes in cell wall composition and cell division/cell differentiation processes (Szechyńska-Hebda et al 2016).…”

LSD1‐, EDS1‐ and PAD4‐dependent conditional correlation among salicylic acid, hydrogen peroxide, water use efficiency and seed yield in Arabidopsis thaliana

“…Furthermore, LSD1 is a condition‐dependent scaffold protein and transcription regulator, and forms dimers with EDS1 (Czarnocka et al ). Recently, we reported that PAD4 and EDS1 can function in woody plants in a similar manner as in Arabidopsis (Ślesak et al , Szechyńska‐Hebda et al , Bernacki et al ).…”

“…Salicylic acid (SA) and reactive oxygen species (ROS), such as H 2 O 2 , are important signaling molecules that regulate CD, photosynthesis, WUE, stomatal conductance and cross‐tolerance processes (Desikan et al , Gechev and Hille , Ślesak et al , Wituszyńska et al , Wituszyńska et al , Szechyńska‐Hebda et al , Bernacki et al , Czarnocka and Karpiński ). They also play a vital role in plant development (Mittler et al , Gawroński et al ) and seed yield control (Abreu and Munné‐Bosch ).…”

Cold-induced changes in cell wall stability determine the resistance of winter triticale to fungal pathogen Microdochium nivale

“…However, based on the general agreement that the cell wall is formed via the successive deposition of cellulose, followed by lignification process, in this way, cellulose provides a key structural pattern for assembly of lignin. Lignification is a tightly regulated and dynamic process subject to post-modulation in response to abiotic and biotic stresses [30,37]. Therefore, the decrease in the porosity of the cellulose network together with the greater stability of lignin formed in cold conditions can reduce the cell wall permeability for fungus-originated enzymes and increase its mechanical strength that prevents hyphae invasion.…”