Poplar plants overexpressing the ubiquitin E3 ligase gene PtrRZFP1 display enhanced resistance against generalist insects

作者：Jia-Yao Tang, Peng Yang, Hao Li, Rui-Quan Wang, Jia-Hui Liu, Keyu Liao, Jiu-Jiu Zhao, Xiang Xiang, Ting Wang, Tian-Tian Chen Guo-Jun Lin, Fang He · 发表于：Journal of Experimental Botany · 年份：2026 · DOI：10.1093/jxb/erag081 · 研究领域：Insect-Plant Interactions and Control、Forest Insect Ecology and Management、Plant Gene Expression Analysis

Forest trees face numerous biotic challenges throughout their life cycle, including pathogens and leaf-chewing insects. Our previous research suggested that certain members of the RING ZINC FINGER PROTEIN (RZFP) family, particularly PtrRZFP1 in Populus trichocarpa, may play a role in insect-plant interactions. In this study, we found that the PtrRZFP1 gene is significantly up-regulated by exogenous methyl jasmonate (MeJA), insect infestation, and mechanical injury. Specifically, overexpression in poplar plants enhances resistance against two major generalist insects, Mythimna separata and Spodoptera frugiperda. Conversely, suppressing this gene results in a reduced ability of the plants to fend off these insects. At the physiological level, our results indicated that PtrRZFP1 positively regulates leaf surface temperature and the rate of photosynthetic electron transport in poplar plants in response to insect attack. In addition, PtrRZFP1 can up-regulate the content of hormones (including abscisic acid, jasmonic acid, and salicylic acid) and lignin in poplar leaves to cope with insects. Transcriptional analysis revealed that PtrRZFP1 activates pathways associated with lignin biosynthesis and jasmonic acid signaling, thereby contributing to insect resistance. Investigations at the protein level also suggested that PtrRZFP1 may interact with proteins involved in biotic stress responses, mediating the complex dynamics of poplar-insect interactions. Overall, these findings undersc...