Krone Mara J, Adhikari Pragya, Singh Pummi, Jamann Tiffany M, Mideros Santiago X
Department of Crop Sciences, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA.
G3 (Bethesda). 2025 Jun 4;15(6). doi: 10.1093/g3journal/jkaf084.
Exserohilum turcicum causes northern corn leaf blight and sorghum leaf blight. While the same species cause disease in both crops, the strains are host-specific. Here, we report the sequence and de novo annotated assemblies of one sorghum- and one maize-specific E. turcicum strain. The strains were sequenced using the PacBio Sequel II system. The total genome length for both assemblies was between 44 and 45 Mb with N50 of ∼2.5 Mb. Ninety-eight percent of the Benchmarking Universal Single-Copy Orthologs (BUSCO) for both assemblies had complete status. The estimated number of genes was 11,762 and 12,029 in the sorghum- and maize-specific isolates, respectively. Funannotate, EffectorP, SignalP, and transcriptome data were used to create functional annotation of each genome. The whole-genome comparison identified ten large-scale inversions and three translocations between the maize- and sorghum-specific strains, along with homologous genes and gene duplications. RNA was sequenced from the maize- and sorghum-specific isolate 10 days post-inoculation in maize and sorghum and from axenic cultures. Gene expression data from planta and axenic growth experiments were compared for each strain. Candidate host-specificity genes were identified by combining results from whole-genome comparison, synteny analysis, gene annotations, and transcriptome data. Overall, this study identified several candidate host-specificity genes that provide insights into E. turcicum interaction with its hosts.
大斑凸脐蠕孢菌会引发玉米大斑病和高粱叶斑病。虽然同一物种在这两种作物上都能致病，但菌株具有宿主特异性。在此，我们报告了一株高粱特异性和一株玉米特异性大斑凸脐蠕孢菌菌株的序列及从头注释组装结果。这些菌株使用PacBio Sequel II系统进行测序。两个组装体的总基因组长度在44至45兆碱基之间，N50约为2.5兆碱基。两个组装体的基准通用单拷贝直系同源基因（BUSCO）中有98%具有完整状态。高粱特异性和玉米特异性分离株的估计基因数量分别为11,762个和12,029个。使用Funannotate、EffectorP、SignalP和转录组数据对每个基因组进行功能注释。全基因组比较确定了玉米特异性和高粱特异性菌株之间的十个大规模倒位和三个易位，以及同源基因和基因重复。在接种后10天，从玉米和高粱中的玉米特异性和高粱特异性分离株以及无菌培养物中对RNA进行测序。比较了每个菌株在植物体内和无菌生长实验中的基因表达数据。通过结合全基因组比较、共线性分析、基因注释和转录组数据的结果，鉴定出候选宿主特异性基因。总体而言，本研究鉴定出了几个候选宿主特异性基因，为深入了解大斑凸脐蠕孢菌与其宿主的相互作用提供了见解。
