Li Huizhong, Cai Yichang, Deng Quanqing, Bao Han, Chen Jianwen, Shen Wankuan
College of Agriculture, South China Agricultural University, Guangzhou, China.
Sugarcane Research Laboratory, South China Agricultural University, Guangzhou, China.
Front Microbiol. 2021 Oct 5;12:746550. doi: 10.3389/fmicb.2021.746550. eCollection 2021.
Sugarcane is an important sugar crop. Sugarcane smut, caused by , is a worldwide sugarcane disease with serious economic losses and lack of effective control measures. Revealing the molecular pathogenesis of is very helpful to the development of effective prevention and control technology. Deubiquitinase removes ubiquitin molecules from their binding substrates and participates in a variety of physiological activities in eukaryotes. Based on the transcriptome sequencing data of two isolates ( and ) of with different pathogenicities, , a gene encoding an OTU1-deubiquitin enzyme, was identified. The positive knockout mutants and complementary mutants of the gene were successfully obtained through polyethylene glycol-mediated protoplast transformation technology. In order to study the possible function of this gene in pathogenicity, phenotypic comparison of the growth, morphology, abiotic stress, sexual mating, pathogenicity, and gene expression levels of the knockout mutants, complementary mutants, and their wild type strains were conducted. The results demonstrated that the gene had almost no effect on abiotic stress, cell wall integrity, growth, and morphology, but was related to the sexual mating and pathogenicity of . The sexual mating ability and pathogenicity between the knockout mutants or between the knockout mutant and wild type were more significantly reduced than between the wild types, the complementary mutants, or the wild types and complementary mutants. The sexual mating between the knockout mutants or between the knockout mutant and wild type could be restored by the exogenous addition of small-molecule signaling substances such as 5 mM cyclic adenosine monophosphate (cAMP) or 0.02 mM tryptophol. In addition, during sexual mating, the expression levels of tryptophol and cAMP synthesis-related genes in the knockout mutant combinations were significantly lower than those in the wild type combinations, while the expression levels in the complementary mutant combinations were restored to the level of the wild type. It is speculated that the gene may be involved in the development of sexual mating and pathogenicity in by regulating the synthesis of the small-molecule signaling substances (cAMP or tryptophol) required during the sexual mating of , thereby providing a molecular basis for the study of the pathogenic mechanisms of .
甘蔗是一种重要的糖料作物。由[病原菌名称未给出]引起的甘蔗黑穗病是一种全球性的甘蔗病害，造成严重的经济损失且缺乏有效的防治措施。揭示[病原菌名称未给出]的分子致病机制对有效防控技术的开发非常有帮助。去泛素酶从其结合底物上移除泛素分子，并参与真核生物中的多种生理活动。基于两种不同致病性的[病原菌名称未给出]分离株（[分离株名称未给出]和[分离株名称未给出]）的转录组测序数据，鉴定出一个编码OTU1去泛素酶的基因[基因名称未给出]。通过聚乙二醇介导的原生质体转化技术成功获得了[基因名称未给出]基因的正向敲除突变体和互补突变体。为了研究该基因在致病性方面可能的功能，对敲除突变体、互补突变体及其野生型菌株的生长、形态、非生物胁迫、有性交配、致病性和基因表达水平进行了表型比较。结果表明，该基因对非生物胁迫、细胞壁完整性、生长和形态几乎没有影响，但与[病原菌名称未给出]的有性交配和致病性有关。敲除突变体之间或敲除突变体与野生型之间的有性交配能力和致病性比野生型之间、互补突变体之间或野生型与互补突变体之间显著降低。敲除突变体之间或敲除突变体与野生型之间的有性交配可通过外源添加5 mM环磷酸腺苷（cAMP）或0.02 mM色醇等小分子信号物质来恢复。此外，在有性交配过程中，敲除突变体组合中色醇和cAMP合成相关基因的表达水平显著低于野生型组合，而互补突变体组合中的表达水平恢复到野生型水平。推测[基因名称未给出]基因可能通过调节[病原菌名称未给出]有性交配过程中所需的小分子信号物质（cAMP或色醇）的合成，参与[病原菌名称未给出]有性交配和致病性的发育，从而为研究[病原菌名称未给出]的致病机制提供分子基础。
