Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, China.
BMC Plant Biol. 2024 Oct 31;24(1):1033. doi: 10.1186/s12870-024-05747-5.
Amorphophallus konjac (A. konjac), a perennial tuberous plant, is widely cultivated for its high konjac glucomannan (KGM) content, a heteropolysaccharide with diverse applications. The cellulose synthase-like (CSL) gene family is known to be a group of processive glycan synthases involved in the synthesis of cell-wall polysaccharides and plays an important role in the biological process of KGM. However, in A. konjac the classification, structure, and function of the AkCSLA superfamily have been studied very little.
Bioinformatics methods were used to identify the 11 AkCSLA genes from the whole genome of Amorphophallus konjac and to systematically analyze their characteristics, phylogenetic evolution, promoter cis-elements, expression patterns, and subcellular locations. Phylogenetic analysis revealed that the AkCSLA gene family can be divided into three subfamilies (Groups I- III), which have close relationships with Arabidopsis. The promoters of most AkCSLA family members contain MBS elements and ABA response elements. Analysis of expression patterns in different tissues showed that most AkCSLAs are highly expressed in the corms. Notably, PEG6000 induced down-regulation of the expression of most AkCSLAs, including AkCSLA11. Subcellular localization results showed that AkCSLA11 was localized to the plasma membrane, Golgi apparatus and endoplasmic reticulum. Transgenic Arabidopsis experiments demonstrated that overexpression of AkCSLA11 reduced the plant's drought tolerance. This overexpression also inhibited the expression of drought response genes and altered the sugar components of the cell wall. These findings provide new insights into the response mechanisms of A. konjac to drought stress and may offer potential genetic resources for improving crop drought resistance.
In conclusion, the study reveals that the AkCSLA11 gene from A. konjac negatively impacts drought tolerance when overexpressed in Arabidopsis. This discovery provides valuable insights into the mechanisms of plant response to drought stress and may guide future research on crop improvement for enhanced resilience.
魔芋（A. konjac）是一种多年生块茎植物，因其富含魔芋葡甘聚糖（KGM）而被广泛种植，KGM 是一种具有多种应用的杂多糖。纤维素合酶样（CSL）基因家族是一类参与细胞壁多糖合成的连续糖基合成酶，在 KGM 的生物过程中发挥着重要作用。然而，在魔芋中，AkCSLA 超家族的分类、结构和功能研究甚少。
利用生物信息学方法从魔芋全基因组中鉴定出 11 个 AkCSLA 基因，并对其特征、系统进化、启动子顺式元件、表达模式和亚细胞定位进行了系统分析。系统进化分析表明，AkCSLA 基因家族可分为三个亚家族（I-III 组），与拟南芥亲缘关系密切。大多数 AkCSLA 家族成员的启动子都含有 MBS 元件和 ABA 反应元件。不同组织表达模式分析表明，大多数 AkCSLAs 在块茎中高度表达。值得注意的是，PEG6000 诱导大多数 AkCSLAs（包括 AkCSLA11）的表达下调。亚细胞定位结果表明，AkCSLA11 定位于质膜、高尔基体和内质网。拟南芥转基因实验表明，过表达 AkCSLA11 降低了植物的耐旱性。这种过表达还抑制了干旱响应基因的表达，并改变了细胞壁的糖组成。这些发现为魔芋应对干旱胁迫的响应机制提供了新的见解，并为提高作物抗旱性提供了潜在的遗传资源。
总之，本研究表明，魔芋中的 AkCSLA11 基因在拟南芥中过表达时会对耐旱性产生负面影响。这一发现为植物应对干旱胁迫的机制提供了有价值的见解，并可能指导未来提高作物抗旱性的研究。
