Huang Rui, Snedden Wayne A, diCenzo George C
Department of Biology Queen's University Kingston Ontario Canada.
Plant Direct. 2022 Jun 8;6(6):e408. doi: 10.1002/pld3.408. eCollection 2022 Jun.
Host/symbiont compatibility is a hallmark of the symbiotic nitrogen-fixing interaction between rhizobia and legumes, mediated in part by plant-produced nodule-specific cysteine-rich (NCR) peptides and the bacterial BacA membrane protein that can act as a NCR peptide transporter. In addition, the genetic and metabolic properties supporting symbiotic nitrogen fixation often differ between compatible partners, including those sharing a common partner, highlighting the need for multiple study systems. Here, we report high-quality nodule transcriptome assemblies for cv. Algonquin and , two legumes able to form compatible symbioses with . The compressed and assemblies consisted of 79,978 and 64,593 contigs, respectively, of which 33,341 and 28,278 were assigned putative annotations, respectively. As expected, the two transcriptomes showed broad similarity at a global level. We were particularly interested in the NCR peptide profiles of these plants, as these peptides drive bacterial differentiation during the symbiosis. A total of 412 and 308 NCR peptides were predicted from the and transcriptomes, respectively, with approximately 9% of the transcriptome of both species consisting of transcripts. Notably, transcripts encoding highly cationic NCR peptides (isoelectric point > 9.5), which are known to have antimicrobial properties, were ∼2-fold more abundant in than in , and ∼27-fold more abundant when considering only NCR peptides in the six-cysteine class. We hypothesize that the difference in abundance of highly cationic NCR peptides explains our previous observation that some rhizobial alleles which can support symbiosis with are unable to support symbiosis with .
宿主/共生体兼容性是根瘤菌与豆科植物之间共生固氮相互作用的一个标志，部分由植物产生的结节特异性富含半胱氨酸（NCR）的肽和可作为NCR肽转运蛋白的细菌BacA膜蛋白介导。此外，支持共生固氮的遗传和代谢特性在兼容的伙伴之间通常存在差异，包括那些共享共同伙伴的伙伴，这突出了对多个研究系统的需求。在这里，我们报告了cv. Algonquin和 这两种能够与 形成兼容共生关系的豆科植物的高质量根瘤转录组组装。压缩后的 和 组装分别由79,978和64,593个重叠群组成，其中分别有33,341和28,278个被赋予了推定注释。正如预期的那样，这两个转录组在全球水平上显示出广泛的相似性。我们特别感兴趣的是这些植物的NCR肽谱，因为这些肽在共生过程中驱动细菌分化。分别从 和 的转录组中预测出总共412个和308个NCR肽，两个物种的转录组中约9%由 转录本组成。值得注意的是，编码具有抗菌特性的高阳离子NCR肽（等电点>9.5）的转录本在 中比在 中丰富约2倍，仅考虑六半胱氨酸类中的NCR肽时则丰富约27倍。我们假设高阳离子NCR肽丰度的差异解释了我们之前的观察结果，即一些能够支持与 共生的根瘤菌 等位基因无法支持与 的共生。
