Xu Shanshan, Shen Chengmeng, Li Chengyun, Dong Wenhan, Yang Genhua
State Key Laboratory for Protection and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, Yunnan, China.
Front Microbiol. 2024 Apr 4;15:1360524. doi: 10.3389/fmicb.2024.1360524. eCollection 2024.
AG-3 is a plant pathogenic fungus that belongs to the group of multinucleate According to its internal transcribed spacer (ITS) cluster analysis and host range, it is divided into TB, PT, and TM subgroups. AG-3 TB mainly causes tobacco target spots, AG-3 PT mainly causes potato black scurf, and AG-3 TM mainly causes tomato leaf blight. In our previous study, we found that all 36 tobacco target spot strains isolated from Yunnan (Southwest China) were classified into AG-3 TB subgroup, while only two of the six tobacco target spot strains isolated from Liaoning (Northeast China) were classified into AG-3 TB subgroup, and the remaining four strains were classified into AG-3 TM subgroup, which had a unique taxonomic status, and there was no previous report on the whole genome information of AG-3 TM subgroup. In this study, the whole genomes of AG-3 strains 3T-1 (AG-3 TM isolated from Liaoning) and MJ-102 (AG-3 TB isolated from Yunnan) isolated from tobacco target spot in Liaoning and Yunnan were sequenced by IIumina and PacBio sequencing platforms. Comparative genomic analysis was performed with the previously reported AG-3 PT strain Rhs1AP, revealing their differences in genomes and virulence factors. The results indicated that the genome size of 3T-1 was 42,103,597 bp with 11,290 coding genes and 49.74% GC content, and the genome size of MJ-102 was 41,908,281 bp with 10,592 coding genes and 48.91% GC content. Through comparative genomic analysis with the previously reported strain Rhs1AP (AG-3 PT), it was found that the GC content between the genomes was similar, but the strains 3T-1 and MJ-102 contained more repetitive sequences. Similarly, there are similarities between their virulence factors, but there are also some differences. In addition, the results of collinearity analysis showed that 3T-1 and MJ-102 had lower similarity and longer evolutionary distance with Rhs1AP, but the genetic relationship between 3T-1 and MJ-102 was closer. This study can lay a foundation for studying the molecular pathogenesis and virulence factors of AG-3, and revealing its genomic composition will also help to develop more effective disease control strategies.
AG-3是一种植物病原真菌，属于多核菌纲。根据其内部转录间隔区（ITS）聚类分析和寄主范围，它被分为TB、PT和TM亚组。AG-3 TB主要引起烟草靶斑病，AG-3 PT主要引起马铃薯黑痣病，AG-3 TM主要引起番茄叶枯病。在我们之前的研究中，我们发现从中国西南部云南省分离出的36株烟草靶斑病菌株均被归类为AG-3 TB亚组，而从中国东北部辽宁省分离出的6株烟草靶斑病菌株中只有2株被归类为AG-3 TB亚组，其余4株被归类为AG-3 TM亚组，该亚组具有独特的分类地位，且此前没有关于AG-3 TM亚组全基因组信息的报道。在本研究中，通过Illumina和PacBio测序平台对从辽宁和云南烟草靶斑病中分离出的AG-3菌株3T-1（从辽宁分离的AG-3 TM）和MJ-102（从云南分离的AG-3 TB）进行了全基因组测序。与先前报道的AG-3 PT菌株Rhs1AP进行了比较基因组分析，揭示了它们在基因组和毒力因子方面的差异。结果表明，3T-1的基因组大小为42,103,597 bp，有11,290个编码基因，GC含量为49.74%，MJ-102的基因组大小为41,908,281 bp，有10,592个编码基因，GC含量为48.91%。通过与先前报道的菌株Rhs1AP（AG-3 PT）进行比较基因组分析，发现基因组之间的GC含量相似，但3T-1和MJ-102菌株含有更多的重复序列。同样，它们的毒力因子之间也有相似之处，但也存在一些差异。此外，共线性分析结果表明，3T-1和MJ-102与Rhs1AP的相似性较低，进化距离较长，但3T-1和MJ-102之间的遗传关系更近。本研究可为研究AG-3的分子发病机制和毒力因子奠定基础，揭示其基因组组成也将有助于制定更有效的病害防治策略。
