Department of Biochemistry, Genetics & Microbiology, Forestry & Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.
PLoS One. 2023 Oct 12;18(10):e0292619. doi: 10.1371/journal.pone.0292619. eCollection 2023.
The Leotiomycetes is a hugely diverse group of fungi, accommodating a wide variety of important plant and animal pathogens, ericoid mycorrhizal fungi, as well as producers of antibiotics. Despite their importance, the genetics of these fungi remain relatively understudied, particularly as they don't include model taxa. For example, sexual reproduction and the genetic mechanisms that underly this process are poorly understood in the Leotiomycetes. We exploited publicly available genomic and transcriptomic resources to identify genes of the mating-type locus and pheromone response pathway in an effort to characterize the mating strategies and behaviors of 124 Leotiomycete species. Our analyses identified a putative a-factor mating pheromone in these species. This significant finding represents the first identification of this gene in Pezizomycotina species outside of the Sordariomycetes. A unique mating strategy was also discovered in Lachnellula species that appear to have lost the need for the primary MAT1-1-1 protein. Ancestral state reconstruction enabled the identification of numerous transitions between homothallism and heterothallism in the Leotiomycetes and suggests a heterothallic ancestor for this group. This comprehensive catalog of mating-related genes from such a large group of fungi provides a rich resource from which in-depth, functional studies can be conducted in these economically and ecologically important species.
外囊菌纲是一类真菌，其多样性非常高，包含了多种重要的植物和动物病原体、杜鹃花类菌根真菌，以及抗生素的生产者。尽管这些真菌非常重要，但它们的遗传学仍然相对研究不足，特别是因为它们不包括模式生物。例如，外囊菌纲中的有性生殖和遗传机制还知之甚少。我们利用公开的基因组和转录组资源，鉴定了交配型基因座和信息素反应途径中的基因，以努力描述 124 种外囊菌的交配策略和行为。我们的分析鉴定了这些物种中的一个假定的 a 因子交配信息素。这一重要发现代表了在除了 Sordariomycetes 以外的 Pezizomycotina 物种中首次鉴定到该基因。我们还在 Lachnellula 物种中发现了一种独特的交配策略，这些物种似乎已经失去了对主要 MAT1-1-1 蛋白的需求。祖先状态重建使我们能够识别出在外囊菌纲中同源同型交配和异型交配之间的许多转换，并表明该组的祖先为异型交配。从如此庞大的真菌群体中获得的这些有关交配的基因的综合目录，为这些在经济和生态上重要的物种进行深入的功能研究提供了丰富的资源。
