Plants have various mechanisms to defend themselves against fungal infection. Previous reports have shown that the extract of Voacanga africana seeds exhibits effective antifungal activity, which attracts many attentions to further identify the exact active constituents from the extract for potential antifungal drugs development. Tabersonine, a terpenoid indole alkaloid produced in many plant species, is the most abundant alkaloid accumulated in V. africana seeds. Further investigation shows that yeast growth is inhibited by tabersonine treatment and this growth inhibition is dose-dependent both on agar plates and in liquid medium. Microscopic analysis indicates that yeast cells with DMSO control treatment are growing very well with globose in shape, while some of tabersonine-treated yeast cells show irregular shape during cultivation. Furthermore, transcriptional analysis shows that tabersonine treatment obviously represses the expression of cell wall mannoprotein encoding genes (DAN1, TIR4) and ergosterol biosynthesis genes (ERG1, ERG2, ERG6, and ERG11), which indicates that tabersonine abundantly accumulated in V. africana seeds achieves its antifungal activity by possibly targeting the formation of cell wall and cell membrane in yeast.

中文翻译：

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植物来源的甘露宁通过抑制酿酒酵母中麦角甾醇生物合成和细胞壁甘露糖蛋白编码基因的表达发挥其抗真菌活性

植物有多种机制来保护自己免受真菌感染。以前的报道表明，非洲苦参种子的提取物具有有效的抗真菌活性，这引起了人们的广泛关注，以进一步确定提取物中的确切活性成分，以开发潜在的抗真菌药物。Tabersonine 是一种在许多植物物种中产生的萜类吲哚生物碱，是V. Africana 中积累的最丰富的生物碱种子。进一步的研究表明，酵母菌的生长受到甘草宁处理的抑制，这种生长抑制在琼脂平板和液体培养基中都是剂量依赖性的。显微镜分析表明，经DMSO对照处理的酵母细胞生长良好，呈球形，而一些经丁香宁处理的酵母细胞在培养过程中呈不规则形状。此外，转录分析表明，甘露宁处理明显抑制细胞壁甘露糖蛋白编码基因（DAN1、TIR4）和麦角甾醇生物合成基因（ERG1、ERG2、ERG6和ERG11）的表达，这表明甘露宁在细胞壁中大量积累。V. Africana种子通过可能靶向酵母中细胞壁和细胞膜的形成来实现其抗真菌活性。