Zhang Huai-Xia, Zhang Yuan, Zhang Bo-Wen, Pan Fei-Fei
College of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, Xinxiang, Henan, China.
Front Plant Sci. 2025 Apr 28;16:1497425. doi: 10.3389/fpls.2025.1497425. eCollection 2025.
The SBP-box gene family, an exclusively plant transcription factor, is critical for plant growth, development, and adaptive responses to both biotic and abiotic stresses. However, its role under non-biological stresses, specifically drought, remains overlooked in pepper plants. In our previous work, we isolated an SBP-box gene, , from the pepper genomic database. Subsequently, we employed virus-induced gene silencing, overexpression, and protein interaction experiments to investigate the function of under drought stress. Our results revealed that drought conditions significantly upregulated expression, whereas ABA treatment suppressed it. Silencing enhanced drought resistance in pepper, with increased stomatal aperture and ABA levels, and reduced stomatal density, water loss rates, and reactive oxygen species (ROS) accumulation compared to control plants. Conversely, overexpression of in decreased drought tolerance, with -overexpressing plants showing reduced ABA sensitivity, lower stomatal aperture and ABA levels, and increased stomatal density and ROS production compared to wild-type plants. Interestingly, under non-stress conditions, core ABA signaling genes (, , , ) exhibited lower expression in -silenced plants compared to controls, whereas this trend was reversed in -overexpressing lines (, , , ). Additionally, was found to interact with , , , and in nucleus. These data suggest that negatively regulates plant responses to drought stress and may interact with these key genes in the ABA signaling pathway to mediate this response.
SBP-box基因家族是植物特有的转录因子，对植物生长、发育以及对生物和非生物胁迫的适应性反应至关重要。然而，其在非生物胁迫特别是干旱胁迫下的作用在辣椒植株中仍被忽视。在我们之前的工作中，我们从辣椒基因组数据库中分离出一个SBP-box基因， 。随后，我们利用病毒诱导基因沉默、过表达和蛋白质相互作用实验来研究 在干旱胁迫下的功能。我们的结果表明，干旱条件显著上调 的表达，而脱落酸（ABA）处理则抑制其表达。与对照植株相比，沉默 增强了辣椒的抗旱性，气孔孔径和ABA水平增加，气孔密度、水分流失率和活性氧（ROS）积累减少。相反，在 中过表达 降低了耐旱性，与野生型植株相比，过表达 的植株对ABA的敏感性降低，气孔孔径和ABA水平较低，气孔密度和ROS产生增加。有趣的是，在非胁迫条件下，与对照相比，核心ABA信号基因（ 、 、 、 ）在沉默 的植株中表达较低，而在过表达 的株系（ 、 、 、 ）中这种趋势则相反。此外，发现 在细胞核中与 、 、 和 相互作用。这些数据表明， 负向调节植物对干旱胁迫的反应，并可能与ABA信号通路中的这些关键基因相互作用来介导这种反应。
