Two aquaporins, LcPIP1;4 and LcPIP1;4a, cooperatively regulate the onset of dormancy of the terminal buds in evergreen perennial litchi ( Litchi chinensis Sonn . )

作者：Xue Tian, Zhi-Qun Zhong, Yu Qi, Mengmeng Ma, Mingchao Yang, Dongcheng Li, Fangyi Zhang, Huicong Wang, Jiyuan Shen, Ren‐Fang Zeng, Xu‐Ming Huang · 发表于：Horticulture Research · 年份：2025 · DOI：10.1093/hr/uhaf122 · 被引用次数：5 · 研究领域：Plant Reproductive Biology、Plant Molecular Biology Research、Polysaccharides and Plant Cell Walls

Abstract Although extensively studied in various plants, the roles of aquaporin proteins in litchi remain unclear. In this study, low moisture content was observed in the dormant terminal buds of litchi. Transcriptome analysis revealed that two aquaporin genes, PLASMA MEMBRANE INTRINSIC PROTEIN 1;4 (LcPIP1;4) and LcPIP1;5, could be remarkably inhibited by exogenous ethylene (ETH), which also reduced the moisture content of litchi buds. Quantitative real-time polymerase chain reaction assays indicated that LcPIP1;4 expression was relatively elevated in the dormancy stage of litchi terminal buds. Inhibition of LcPIP1;4 in the buds of litchi during the growth stage delayed the onset of dormancy, resulting in a significantly reduced dormancy rate and increased moisture content. Further study indicated that LcPIP1;4 interacts with LcPIP1;4a, and they are capable of self-interaction. Silencing of LcPIP1;4a in litchi buds resulted in a phenotype consistent with silencing of LcPIP1;4. Additionally, simultaneous silencing of both LcPIP1;4 and LcPIP1;4a resulted in a more severe bud dormancy phenotype. Moreover, LcPIP1;4 was directly upregulated by LcRAP2.4. Silencing of LcRAP2.4 also delayed the onset of dormancy in litchi terminal buds, which is regulated by LcSVP2. ETH treatment at 1000 mg/l significantly downregulated the expression of LcPIP1;4 and LcRAP2.4, but had no significant effect on LcPIP1;4a. In contrast, abscisic acid (ABA) treatment at 200 mg/l significantly upregulated ...