Title:	Guard cell and whole plant expression of AtTOR improves performance under drought and enhances water use efficiency.
Authors:	LIU, L. GAO, P. SHENG, H. BAKSHI, A. SCHNEIDER, D. XIANG, D. BABIC, V. REN, M. BURBRIDGE, C. NGUYEN, H. WANG, S. ARMENTA-MEDINA, A. MORA-MACIAS, J. SHARPE, A. POZNIAK, C. MAGALHAES, J. V. de DATLA, R. KOCHIAN, L.
Affiliation:	LI LIU, UNIVERSITY OF SASKATCHEWAN; PENG GAO, UNIVERSITY OF SASKATCHEWAN; HUAJIN SHENG, UNIVERSITY OF SASKATCHEWAN; ACHALA BAKSHI, UNIVERSITY OF SASKATCHEWAN; DAVID SCHNEIDER, UNIVERSITY OF SASKATCHEWAN; DAOQUAN XIANG, NATIONAL RESEARCH COUNCIL CANADA; VIVIJAN BABIC, NATIONAL RESEARCH COUNCIL CANADA; MAOZHI REN, CHINESE ACADEMY OF AGRICULTURAL SCIENCES; CONNOR BURBRIDGE, UNIVERSITY OF SASKATCHEWAN; HANH NGUYEN, UNIVERSITY OF SASKATCHEWAN; SHENG WANG, UNIVERSITY OF SASKATCHEWAN; ALMA ARMENTA-MEDINA, INSTITUTO NACIONAL DE INVESTIGACIONES FORESTALES, AGRICOLAS Y PECUARIAS; JAVIER MORA-MACIAS, UNIVERSITY OF SASKATCHEWAN; ANDREW SHARPE, UNIVERSITY OF SASKATCHEWAN; CURTIS POZNIAK, UNIVERSITY OF SASKATCHEWAN; JURANDIR VIEIRA DE MAGALHAES, CNPMS; RAJU DATLA, UNIVERSITY OF SASKATCHEWAN; LEON KOCHIAN, UNIVERSITY OF SASKATCHEWAN.
Date Issued:	2025
Citation:	Journal of Biological Chemistry, v.. 301, n. 6, 110220, 2025.
Description:	Water use efficiency is an important target for breeding of improved drought resistance. Minimizing leaf transpirational water loss plays a key role in drought resistance. But this reduces CO2 levels in leaves, which often reduces photosynthetic efficiency and yield. Signaling pathways play important roles in stress responses, and identifying the molecular, biochemical, and physiological determinants underlying drought signaling may offer new drought mitigating strategies. To explore these possibilities, and because of the importance of stomata in drought response and photosynthesis, we employed guard cell (GC)-targeted and constitutive overexpression of the Target of Rapamycin (TOR) kinase, a master regulator of signaling networks, in transgenic Arabidopsis. To investigate the impact of these AtTOR transgenes in drought, we conducted physiological and molecular investigations into drought responses, including leaf water loss, photosynthetic CO2 assimilation, stomatal H2O/CO2 conductance, leaf chlorophyll content, and global gene expression in response to drought in wild-type and AtTOR-expressing Arabidopsis. Links between both guard cell-localized and whole plant AtTOR overexpression were identified, revealing TOR is involved in conservation of water and sustained photosynthetic performance, along with identification of genes associated with drought response in WT versus AtTOR-expressing transgenic lines. These findings suggest that targeted guard cell AtTOR expression should help achieve a balance between plant water conservation during drought, and maintaining plant performance, by minimizing reductions in photosynthesis. Manipulation of guard cell AtTOR expression could be an effective avenue for developing crops with enhanced drought resistance and increased yield under drought stress, resulting in enhanced water use efficiency.
Thesagro:	Melhoramento Genético Vegetal Resistência a Seca Fotossíntese
NAL Thesaurus:	Transpiration Water use efficiency Leaf conductance Photosynthesis Guard cells Arabidopsis Drought tolerance
Keywords:	Expressão ectópica Célula de guarda Condutância foliar
DOI:	https://doi.org/10.1016/j.jbc.2025.110220
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CNPMS)