Harvey Aaron, van den Berg Noëlani, Swart Velushka
Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa.
Hans Merensky Chair in Avocado Research, Forestry & Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.
Front Plant Sci. 2025 Jan 29;15:1474781. doi: 10.3389/fpls.2024.1474781. eCollection 2024.
The avocado industry faces a significant threat from the hemibiotrophic oomycete pathogen . A variably expressed defence gene during an avocado infection trial was a (). WAK and WAK-Like (WAKL) proteins are known to bind to fragmented pectin (oligogalacturonides) produced during pathogen penetration, thereby activating downstream defence-related pathways. To better understand the -avocado defence interaction, this gene family was assessed using methods. In this study, previously generated RNA-sequencing data were used to associate genes with the defence response, followed by promoter- and phylogenetic analysis of these genes/proteins. The predicted proteins from these genes were modelled with AlphaFold2, and structural similarity across different rootstocks, as well as their binding affinity for oligogalacturonides, were assessed. The analysis identified 14 (s and 62 s across the West-Indian (pure accession reference), Dusa, Leola™ and R0.12 avocado rootstock genomes. These genes showed distribution across the West-Indian genome's chromosomes, with MCScanX analyses predicting tandem duplications. expression profiles were compared, implicating five s in defence. Phylogenetic and promoter analyses were conducted to predict associated defence-related pathways, focusing on stress and phytohormone-responsive pathways. Structural differences and varying oligogalacturonide binding affinities of PaWAK/WAKLs were predicted across rootstocks. These defence-related genes could be incorporated into a molecular screening tool to improve the development of resistant avocado rootstocks.
鳄梨产业面临着来自半活体营养型卵菌病原体的重大威胁。在鳄梨感染试验中一个表达可变的防御基因是一个（）。已知细胞壁相关激酶（WAK）和类细胞壁相关激酶（WAKL）蛋白会与病原体穿透过程中产生的碎片化果胶（低聚半乳糖醛酸）结合，从而激活下游与防御相关的途径。为了更好地理解（）与鳄梨的防御相互作用，使用（）方法对该基因家族进行了评估。在本研究中，先前生成的RNA测序数据被用于将基因与防御反应相关联，随后对这些基因/蛋白质进行启动子和系统发育分析。这些基因预测的蛋白质用AlphaFold2进行建模，并评估了不同砧木之间的结构相似性以及它们对低聚半乳糖醛酸的结合亲和力。分析在西印度（纯系 accession 参考）、杜萨、Leola™ 和 R0.12 鳄梨砧木基因组中鉴定出14个（）（西印度基因组中有62个）。这些基因分布在西印度基因组的染色体上，MCScanX分析预测存在串联重复。比较了（）的表达谱，表明有5个（）参与防御。进行了系统发育和启动子分析以预测相关的防御相关途径，重点是应激和植物激素反应途径。预测了不同砧木间PaWAK/WAKLs的结构差异和不同的低聚半乳糖醛酸结合亲和力。这些与防御相关的基因可纳入分子筛选工具，以促进抗性鳄梨砧木的培育。
