Wang Zhu-Qing, Sun Sheng-Ren, Wang Hao-Yu, Bi Zheng-Wang, Chang Hai-Long, Zhang Shuo-Hang, Chen Jun-Lv, Qin Yuan-Xia, Wu Jian-Tao, Zhang Wei, Xu Huan-Ying, Gao San-Ji, Wang Qin-Nan
Institute of Nanfan and Seed Industry, Guangdong Academy of Sciences, Guangzhou, 510000, China.
National Key Laboratory for Tropical Crop Breeding, Haikou, 571101, Hainan, China.
Plant Cell Rep. 2025 Mar 25;44(4):85. doi: 10.1007/s00299-025-03472-3.
A total of 54 genes of membrane attack complex/perforin (MACPF) superfamily were identified in Saccharum complex and function divergence among SsaCAD-like genes were present in plant against stressors. The membrane attack complex/perforin (MACPF) superfamily belongs to pore-forming proteins involving in innate and adaptive immunity in eukaryotes. The constitutively activated cell death (CAD) proteins contained the MACPF domain participate in plant defense responses under adverse conditions. However, the characteristics and functions of CAD-like genes in sugarcane are still poorly understood. In this study, 54 CAD-like genes were identified in three genomes from Saccharum complex including two clones (Np-X and AP85-441) of Saccharum spontaneum and a clone (Yunnan2009-3) of Erianthus rufipilus. All CAD-like genes were categorized into five phylogenetic groups (I-V). Various cis-acting elements related to stress responses, such as phytohormone response elements, were found in promoter regions. Transcriptome and RT-qPCR analysis demonstrated these genes possessing diverse expression profiles. The SsaCAD1-like1 gene was upregulated in sugarcane cultivars after cold treatment and infection by Xanthomonas albilineans (Xa) causing leaf scald. Meanwhile, this gene was downregulated under drought and ABA treatments but was upregulated and then downregulated across time-points of SA treatment. The SsaCAD4-like1 gene was downregulated under five abiotic stressors. Expression levels of two alleles (SsaCAD2-like1/2) were significantly decreased under all abiotic stressors except for salinity treatment. Similar expression patterns of three alleles (SsaCAD3-like1/2/4) were found under abiotic stress. The SsaCAD1-like1 exhibited a negative role but SsaCAD3-like2/4 acted as positive roles in transgenic Arabidopsis lines against bacterial pathogen infection. Our results provide novel gene resources for developing disease-resistant cultivars in sugarcane.
在甘蔗复合体中总共鉴定出54个膜攻击复合物/穿孔素（MACPF）超家族基因，并且在植物应对胁迫时，SsaCAD样基因之间存在功能差异。膜攻击复合物/穿孔素（MACPF）超家族属于参与真核生物固有免疫和适应性免疫的成孔蛋白。含有MACPF结构域的组成型激活细胞死亡（CAD）蛋白在不利条件下参与植物防御反应。然而，甘蔗中CAD样基因的特征和功能仍知之甚少。在本研究中，从甘蔗复合体的三个基因组中鉴定出54个CAD样基因，包括两个甘蔗野生种克隆（Np-X和AP85-441）以及一个黑穗病甘蔗克隆（云南2009-3）。所有CAD样基因被分为五个系统发育组（I-V）。在启动子区域发现了各种与胁迫反应相关的顺式作用元件，如植物激素反应元件。转录组和RT-qPCR分析表明这些基因具有不同的表达谱。SsaCAD1-like1基因在甘蔗品种经冷处理以及被引起叶烧病的白叶病菌（Xa）感染后上调。同时，该基因在干旱和脱落酸处理下下调，但在水杨酸处理的各个时间点先上调后下调。SsaCAD4-like1基因在五种非生物胁迫下下调。两个等位基因（SsaCAD2-like1/2）的表达水平在除盐处理外的所有非生物胁迫下均显著降低。在非生物胁迫下发现三个等位基因（SsaCAD3-like1/2/4）具有相似的表达模式。在转基因拟南芥品系抵抗细菌病原体感染方面，SsaCAD1-like1发挥负作用，而SsaCAD3-like2/4发挥正作用。我们 的结果为培育抗病甘蔗品种提供了新的基因资源。
