文献类型： 外文期刊

作者： Fang, Yuanyuan ¹ ; Wang, Dan ¹ ; Xiao, Liang ¹ ; Quan, Mingyang ¹ ; Qi, Weina ¹ ; Song, Fangyuan ¹ ; Zhou, Jiaxuan ¹ ; Liu, Xin ³ ; Qin, Shitong ¹ ; Du, Qingzhang ¹ ; Liu, Qing ⁴ ; El-Kassaby, Yousry A. ⁵ ; Zhang, Deqiang ¹ ;

作者机构： 1.Beijing Forestry Univ, Coll Biol Sci & Technol, Natl Engn Res Ctr Tree Breeding & Ecol Restorat, 35 Qinghua East Rd, Beijing 100083, Peoples R China

2.Beijing Forestry Univ, Coll Biol Sci & Technol, Key Lab Genet & Breeding Forest Trees & Ornamental, Minist Educ, 35 Qinghua East Rd, Beijing 100083, Peoples R China

3.Beijing Acad Agr & Forestry Sci, Inst Forestry & Pomol, Beijing 100093, Peoples R China

4.Inst Agr & Food Res, CSIRO Agr & Food, Canberra, ACT 2601, Australia

5.Univ British Columbia, Fac Forestry, Forest Sci Ctr, Dept Forest & Conservat Sci, Vancouver, BC V6T 1Z4, Canada

期刊名称：PLANT PHYSIOLOGY （ 影响因子：7.4； 五年影响因子：8.7 ）

ISSN： 0032-0889

年卷期： 2023 年

页码：

收录情况： SCI

摘要： Drought stress limits woody species productivity and influences tree distribution. However, dissecting the molecular mechanisms that underpin drought responses in forest trees can be challenging due to trait complexity. Here, using a panel of 300 Chinese white poplar (Populus tomentosa) accessions collected from different geographical climatic regions in China, we performed a genome-wide association study (GWAS) on seven drought-related traits and identified PtoWRKY68 as a candidate gene involved in the response to drought stress. A 12-bp insertion and/or deletion and three nonsynonymous variants in the PtoWRKY68 coding sequence categorized natural populations of P. tomentosa into two haplotype groups, PtoWRKY68(hap1) and PtoWRKY68(hap2). The allelic variation in these two PtoWRKY68 haplotypes conferred differential transcriptional regulatory activities and binding to the promoters of downstream abscisic acid (ABA) efflux and signaling genes. Overexpression of PtoWRKY68(hap1) and PtoWRKY68(hap2) in Arabidopsis (Arabidopsis thaliana) ameliorated the drought tolerance of two transgenic lines and increased ABA content by 42.7% and 14.3% compared to wild-type plants, respectively. Notably, PtoWRKY68(hap1) (associated with drought tolerance) is ubiquitous in accessions in water-deficient environments, whereas the drought-sensitive allele PtoWRKY68(hap2) is widely distributed in well-watered regions, consistent with the trends in local precipitation, suggesting that these alleles correspond to geographical adaptation in Populus. Moreover, quantitative trait loci analysis and an electrophoretic mobility shift assay showed that SHORT VEGETATIVE PHASE (PtoSVP.3) positively regulates the expression of PtoWRKY68 under drought stress. We propose a drought tolerance regulatory module in which PtoWRKY68 modulates ABA signaling and accumulation, providing insight into the genetic basis of drought tolerance in trees. Our findings will facilitate molecular breeding to improve the drought tolerance of forest trees. Allelic variation in transcription factor PtoWRKY68 affects its transcriptional regulatory activity, resulting in different degrees of drought tolerance through the abscisic acid pathway in Populus.