Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06520, USA.
Department of Chemistry, Yale University, New Haven, CT, 06520, USA.
Nucleic Acids Res. 2021 Dec 2;49(21):12422-12432. doi: 10.1093/nar/gkab1077.
Fungal pathogens represent an expanding global health threat for which treatment options are limited. Self-splicing group II introns have emerged as promising drug targets, but their development has been limited by a lack of information on their distribution and architecture in pathogenic fungi. To meet this challenge, we developed a bioinformatic workflow for scanning sequence data to identify unique RNA structural signatures within group II introns. Using this approach, we discovered a set of ubiquitous introns within thermally dimorphic fungi (genera of Blastomyces, Coccidioides and Histoplasma). These introns are the most biochemically reactive group II introns ever reported, and they self-splice rapidly under near-physiological conditions without protein cofactors. Moreover, we demonstrated the small molecule targetability of these introns by showing that they can be inhibited by the FDA-approved drug mitoxantrone in vitro. Taken together, our results highlight the utility of structure-based informatic searches for identifying riboregulatory elements in pathogens, revealing a striking diversity of reactive self-splicing introns with great promise as antifungal drug targets.
真菌病原体对全球健康构成了日益严重的威胁，但可用的治疗方法有限。自我剪接的 II 组内含子已成为很有前途的药物靶点，但由于缺乏有关其在致病真菌中的分布和结构的信息，其发展受到限制。为了应对这一挑战，我们开发了一种生物信息学工作流程，用于扫描序列数据以识别 II 组内含子中的独特 RNA 结构特征。使用这种方法，我们在热二形真菌（芽生菌属、球孢子菌属和组织胞浆菌属）中发现了一组普遍存在的内含子。这些内含子是迄今为止报道的生化反应性最强的 II 组内含子，它们在没有蛋白质辅助因子的情况下，在接近生理条件下快速自我剪接。此外，我们通过证明它们可以在体外被 FDA 批准的药物米托蒽醌抑制，证明了这些内含子的小分子靶向性。总之，我们的研究结果强调了基于结构的信息搜索在鉴定病原体中的核糖调控元件方面的效用，揭示了具有很大作为抗真菌药物靶点的反应性自我剪接内含子的惊人多样性。
