PDF(Pubmed)
Abstract：
Scleromitrula shiraiana is a necrotrophic fungus with a narrow host range, and is one of the main causal pathogens of mulberry sclerotial disease. However, its molecular mechanisms and pathogenesis are unclear. Here, we report a 39.0 Mb high-quality genome sequence for S. shiraiana strain SX-001. The S. shiraiana genome contains 11,327 protein-coding genes. The number of genes and genome size of S. shiraiana are similar to most other Ascomycetes. The cross-similarities and differences of S. shiraiana with the closely related Sclerotinia sclerotiorum and Botrytis cinerea indicated that S. shiraiana differentiated earlier from their common ancestor. A comparative genomic analysis showed that S. shiraiana has fewer genes encoding cell wall-degrading enzymes (CWDEs) and effector proteins than that of S. sclerotiorum and B. cinerea, as well as many other Ascomycetes. This is probably a key factor in the weaker aggressiveness of S. shiraiana to other plants. S. shiraiana has many species-specific genes encoding secondary metabolism core enzymes. The diversity of secondary metabolites may be related to the adaptation of these pathogens to specific ecological niches. However, melanin and oxalic acid are conserved metabolites among many Sclerotiniaceae fungi, and may be essential for survival and infection. Our results provide insights into the narrow host range of S. shiraiana and its adaptation to mulberries.
摘要：
Scleromitrulashiraiana是一种坏死真菌，寄主范围窄，是桑树硬化性疾病的主要病原之一。然而,其分子机制和发病机制尚不清楚。这里,我们报道了一个39.0Mb的高质量基因组序列。Shiraiana基因组包含11,327个蛋白质编码基因。Shiraiana的基因数量和基因组大小与大多数其他子囊菌相似。Shiraiana与密切相关的核盘菌和灰葡萄孢菌的交叉相似性和差异表明Shiraiana与它们的共同祖先较早分化。比较基因组分析表明，与硬化S.c.cinerea和B.cinerea相比，shiraiana具有更少的编码细胞壁降解酶（CWDEs）和效应蛋白的基因，以及许多其他子囊。这可能是S.shiraiana对其他植物的攻击性较弱的关键因素。Shiraiana具有许多编码次级代谢核心酶的物种特异性基因。次生代谢产物的多样性可能与这些病原体对特定生态位的适应有关。然而,黑色素和草酸是许多菌科真菌中的保守代谢产物，并且可能是生存和感染所必需的。我们的结果提供了有关Shiraiana的狭窄寄主范围及其对桑树的适应性的见解。
