Li Lianzheng, Jin Zhuoying, Huang Rui, Zhou Jiaxuan, Song Fangyuan, Yao Liangchen, Li Peng, Lu Wenjie, Xiao Liang, Quan Mingyang, Zhang Deqiang, Du Qingzhang
National Engineering Research Center of Tree breeding and Ecological restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P.R. China.
Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P.R. China.
Plant Cell Environ. 2023 Jan;46(1):150-170. doi: 10.1111/pce.14471. Epub 2022 Nov 3.
Stomata are essential for photosynthesis and abiotic stress tolerance. Here, we used multiomics approaches to dissect the genetic architecture and adaptive mechanisms that underlie stomatal morphology in Populus tomentosa juvenile natural population (303 accessions). We detected 46 candidate genes and 15 epistatic gene-pairs, associated with 5 stomatal morphologies and 18 leaf development and photosynthesis traits, through genome-wide association studies. Expression quantitative trait locus mapping revealed that stomata-associated gene loci were significantly associated with the expression of leaf-related genes; selective sweep analysis uncovered significant differentiation in the allele frequencies of genes that underlie stomatal variations. An allelic regulatory network operating under drought stress and adequate precipitation conditions, with three key regulators (DUF538, TRA2 and AbFH2) and eight interacting genes, was identified that might regulate leaf physiology via modulation of stomatal shape and density. Validation of candidate gene variations in drought-tolerant and F hybrid populations of P. tomentosa showed that the DUF538, TRA2 and AbFH2 loci cause functional stabilisation of spatiotemporal regulatory, whose favourable alleles can be faithfully transmitted to offspring. This study provides insights concerning leaf physiology and stress tolerance via the regulation of stomatal determination in perennial plants.
气孔对于光合作用和非生物胁迫耐受性至关重要。在此，我们运用多组学方法剖析毛白杨天然幼龄种群（303个种质）气孔形态的遗传结构和适应机制。通过全基因组关联研究，我们检测到46个候选基因和15个上位性基因对，它们与5种气孔形态以及18个叶片发育和光合作用性状相关。表达数量性状位点定位显示，与气孔相关的基因座与叶片相关基因的表达显著相关；选择性清除分析揭示了气孔变异相关基因等位基因频率的显著分化。我们鉴定出一个在干旱胁迫和充足降水条件下运行的等位基因调控网络，其中有三个关键调控因子（DUF538、TRA2和AbFH2）以及八个相互作用基因，它们可能通过调节气孔形状和密度来调控叶片生理。在毛白杨耐旱和F杂交种群中对候选基因变异进行验证表明，DUF538、TRA2和AbFH2基因座导致时空调控的功能稳定，其有利等位基因能够忠实地传递给后代。本研究通过对多年生植物气孔决定的调控，为叶片生理和胁迫耐受性提供了见解。
