Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
Department of Agricultural, Environmental and Food Sciences, University of Molise, Campobasso 86100, Italy.
bioRxiv. 2023 Jun 9:2023.03.25.534224. doi: 10.1101/2023.03.25.534224.
Fungi in the basidiomycete genus are the most prevalent eukaryotic microbes resident on the skin of human and other warm-blooded animals and have been implicated in skin diseases and systemic disorders. Analysis of genomes revealed that key adaptations to the skin microenvironment have a direct genomic basis, and the identification of mating/meiotic genes suggests a capacity to reproduce sexually, even though no sexual cycle has yet been observed. In contrast to other bipolar or tetrapolar basidiomycetes that have either two linked mating-type-determining ( ) loci or two loci on separate chromosomes, in species studied thus far the two loci are arranged in a pseudobipolar configuration (linked on the same chromosome but capable of recombining). By incorporating newly generated chromosome-level genome assemblies, and an improved phylogeny, we infer that the pseudobipolar arrangement was the ancestral state of this group and revealed six independent transitions to tetrapolarity, seemingly driven by centromere fission or translocations in centromere- flanking regions. Additionally, in an approach to uncover a sexual cycle, strains were engineered to express different alleles in the same cell. The resulting strains produce hyphae reminiscent of early steps in sexual development and display upregulation of genes associated with sexual development as well as others encoding lipases and a protease potentially relevant for pathogenesis of the fungus. Our study reveals a previously unseen genomic relocation of mating-type loci in fungi and provides insight towards the discovery of a sexual cycle in , with possible implications for pathogenicity.
, the dominant fungal group of the mammalian skin microbiome, is associated with numerous skin disorders. Sexual development and yeast-to-hyphae transitions, governed by genes at two mating-type ( ) loci, are thought to be important for fungal pathogenicity. However, sexual reproduction has never been observed. Here, we used chromosome-level assemblies and comparative genomics to uncover unforeseen transitions in loci organization within , possibly related with fragility of centromeric-associated regions. Additionally, by expressing different alleles in the same cell, we show that can undergo hyphal development and this phenotype is associated with increased expression of key mating genes along with other genes known to be virulence factors, providing a possible connection between hyphal development, sexual reproduction, and pathogenicity.
担子菌属真菌是最常见的真核微生物，栖息在人和其他温血动物的皮肤上，与皮肤疾病和全身性疾病有关。基因组分析表明，对皮肤微环境的关键适应具有直接的基因组基础，交配/减数分裂基因的鉴定表明其具有有性繁殖的能力，尽管尚未观察到有性循环。与其他双极或四极担子菌不同，这些担子菌要么有两个连锁的交配型决定（ ）基因座，要么有两个 基因座位于不同的染色体上，而在迄今研究的 物种中，这两个 基因座以假双极构型排列（位于同一染色体上，但可重组）。通过整合新生成的染色体水平基因组组装和改进的 系统发育，我们推断假双极排列是该组的原始状态，并揭示了六个独立的四极性转变，似乎是由着丝粒裂变或着丝粒周围区域的易位驱动的。此外，在揭示有性循环的方法中，将 菌株工程改造为在同一细胞中表达不同的 等位基因。由此产生的菌株产生类似于有性发育早期步骤的菌丝，并且显示与有性发育相关的基因以及其他编码脂酶和可能与真菌发病机制相关的蛋白酶的基因上调。我们的研究揭示了真菌中交配型基因座以前未被发现的基因组重定位，并为在 中发现有性循环提供了深入了解，这可能对致病性有影响。
，哺乳动物皮肤微生物群的主要真菌群，与许多皮肤疾病有关。由两个交配型（ ）基因座上的基因控制的有性发育和酵母到菌丝的转变被认为对真菌的致病性很重要。然而，从未观察到 有性繁殖。在这里，我们使用染色体水平的组装和比较基因组学来揭示 中 基因座组织的意外转变，这可能与着丝粒相关区域的脆弱性有关。此外，通过在同一细胞中表达不同的 等位基因，我们表明 可以进行菌丝发育，这种表型与关键交配基因的表达增加以及其他已知作为毒力因子的基因有关，为菌丝发育、有性繁殖和致病性之间提供了可能的联系。
