Natural variation ingoverns drought tolerance by orchestrating xylem remodeling and lignin metabolism in

Source: PubMed Central Open Access, NCBI / U.S. National Library of Medicine

Drought stress severely limits the growth of perennial trees. Xylem structure is central to water conduction; however, lignin monomer composition driving xylem remodeling for drought adaptation remains enigmatic. By integrating multi-omics analyses, genotype-environment association analysis, and metabolite-based genome-wide association studies, we identifiedas a key gene associated with precipitation-related traits and the aridity index in. This variation in association was linked to coniferyl alcohol and ferulic acid, two metabolites related to guaiacyl (G)-lignin monomer biosynthesis. Overexpressingenhanced drought tolerance in transgenic poplar by promoting xylem remodeling associated with a decreased lignin S/G ratio. Mechanistically, drought-induced Casignaling activates PtoCPK3 to phosphorylate PtoERF72 at Ser, enhancing its activation ofand direct repression of. Synergistic repression ofby PtoWOX13b reduces glycosylation of G-monomer precursors, favoring ferulic acid and coniferyl alcohol accumulation. Furthermore, natural variants inanddrive geographic divergence, with the_genotype conferring superior drought resilience via elevated phosphorylation efficiency. This module links drought signaling to xylem remodeling, providing genetic targets for breeding drought-resilient trees. The protein kinaseregulates drought adaptation by lignin metabolism in. teaser