CsREV-CsTCP4-CsVND7 module shapes xylem patterns differentially between stem and leaf to enhance tea plant tolerance to drought

• Published in: Cell reports (Cambridge) Vol. 43; no. 4; p. 113987
• Main Authors: Li, Jiayang, Ren, Jiejie, Lei, Xingyu, Fan, Wenmin, Tang, Lei, Zhang, Qiqi, Bao, Zhulatai, Zhou, Wenfei, Bai, Juan, Zhang, Yuzhou, Gong, Chunmei
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 23.04.2024; Elsevier
• Subjects: Adaptation, Physiological; Camellia sinensis - genetics; Camellia sinensis - metabolism; Camellia sinensis - physiology; CP: Molecular biology; CP: Plants; development; drought; Droughts; Gene Expression Regulation, Plant; HD-ZIP III; leaf curling; Plant Leaves - metabolism; Plant Leaves - physiology; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Stems - metabolism; Plant Stems - physiology; tea plant; xylem; Xylem - metabolism; xylem; CP: Plants; development; drought; tea plant; leaf curling; CP: Molecular biology; HD-ZIP III
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2024.113987

Cultivating drought-tolerant tea varieties enhances both yield and quality of tea plants in northern China. However, the mechanisms underlying their drought tolerance remain largely unknown. Here we identified a key regulator called CsREV, which differentially regulates xylem patterns between leaves and stems, thereby conferring drought tolerance in tea plants. When drought occurs, upregulation of CsREV activates the CsVND7a-dependent xylem vessel differentiation. However, when drought persists, the vessel differentiation is hindered as CsVND7a is downregulated by CsTCP4a. This, combined with the CsREV-promoted secondary-cell-wall thickness of xylem vessel, leads to the enhanced curling of leaves, a characteristic closely associated with plant drought tolerance. Notably, this inhibitory effect of CsTCP4a on CsVND7a expression is absent in stems, allowing stem xylem vessels to continuously differentiate. Overall, the CsREV-CsTCP4-CsVND7 module is differentially utilized to shape the xylem patterns in leaves and stems, potentially balancing water transportation and utilization to improve tea plant drought tolerance. [Display omitted] •CsREV is swiftly upregulated under drought, affecting tea leaf and stem•CsREV influences CsVND7a expression independently and in conjunction with CsTCP4a•CsREV-CsTCP4a-CsVND7a module orchestrates distinct xylem patterns in leaf and stem•Module-directed xylem patterns of leaf and stem together improve drought tolerance Li et al. present a mechanistic framework elucidating the regulatory role of CsREV in vein xylem patterns and its impact on the upward leaf curling and stem structure. Enhancing our understanding of the molecular underpinnings of plant drought resistance, this study provides strategic guidance for breeding drought-resilient tea cultivars.