Lan Yanhong, Gong Fangyi, Liu Xiaojun, Liu Duchen, Liang Genyun, Li Chun, Xia Feng, Li Yifan, Fang Chao, Cai Peng
Vegetable Germplasm Innovation and Variety Improvement Key Laboratory of Sichuan Province, Horticulture Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610066, China.
Key Laboratory of Horticultural Crops Biology and Germplasm Enhancement in Southwest Regions, Ministry of Agriculture and Rural Affairs of the P.R. China, Chengdu, 610066, China.
BMC Plant Biol. 2025 Aug 2;25(1):1018. doi: 10.1186/s12870-025-07047-y.
Eggplant (Solanum melongena L.), a nutritionally valuable solanaceous crop, exhibits pronounced sensitivity to cold stress, which limits its growth and development. Cytochrome P450 (CYP450) enzymes are widely implicated in plant developmental regulation and abiotic stress responses; however, their functional roles in eggplant remain unexplored.
In this study, we systematically identified 176 SmCYP450 homologs in the eggplant genome, which were phylogenetically classified into 24 distinct subfamilies. Evolutionary analysis revealed that segmental duplication events predominantly drove the expansion of the SmCYP450 family, and codon usage bias within these genes was primarily shaped by natural selection pressures. Notably, transcriptomic profiling identified SmCYP82C1 as a cold-responsive candidate, displaying significant upregulation under cold stress. Heterologous overexpression of SmCYP82C1 in Arabidopsis thaliana enhanced plant cold tolerance, as evidenced by significantly reduced malondialdehyde (MDA) accumulation and elevated activities of key antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), under cold stress relative to wild-type controls. Furthermore, transgenic lines exhibited upregulated expression of cold-signaling regulators (CBF1/2/3, ICE1) and the stress-responsive marker COR47, suggesting activation of conserved cold-adaptation pathways. Yeast one-hybrid and dual-luciferase reporter assays demonstrated that the zinc-finger transcription factor SmZIP1 directly binds to the SmCYP82C1 promoter to transcriptionally activate its expression.
This study therefore offers a new gene target to improve cold stress tolerance in eggplant and reveals that SmCYP82C1 enhances cold tolerance through dual mechanisms: mitigating oxidative damage via antioxidant system potentiation and modulating stress-associated gene networks.
茄子（Solanum melongena L.）是一种具有重要营养价值的茄科作物，对冷胁迫表现出明显的敏感性，这限制了其生长发育。细胞色素P450（CYP450）酶广泛参与植物发育调控和非生物胁迫反应；然而，它们在茄子中的功能作用仍未得到探索。
在本研究中，我们在茄子基因组中系统鉴定了176个SmCYP450同源物，它们在系统发育上被分为24个不同的亚家族。进化分析表明，片段重复事件主要推动了SmCYP450家族的扩张，这些基因内的密码子使用偏好主要由自然选择压力塑造。值得注意的是，转录组分析确定SmCYP82C1为冷响应候选基因，在冷胁迫下显著上调。在拟南芥中异源过表达SmCYP82C1增强了植物的耐寒性，与野生型对照相比，在冷胁迫下丙二醛（MDA）积累显著减少，关键抗氧化酶过氧化氢酶（CAT）、超氧化物歧化酶（SOD）和过氧化物酶（POD）的活性升高，证明了这一点。此外，转基因株系中冷信号调节因子（CBF1/2/3、ICE1）和胁迫响应标记COR47的表达上调，表明保守的冷适应途径被激活。酵母单杂交和双荧光素酶报告基因分析表明，锌指转录因子SmZIP1直接结合到SmCYP82C1启动子上，转录激活其表达。
因此，本研究为提高茄子的冷胁迫耐受性提供了一个新的基因靶点，并揭示SmCYP82C1通过双重机制增强耐寒性：通过增强抗氧化系统减轻氧化损伤和调节胁迫相关基因网络。
