State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, 712100, Yangling, Shaanxi, China.
Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK.
Nat Commun. 2019 Jan 21;10(1):359. doi: 10.1038/s41467-018-08180-z.
Prions are proteins that can fold into multiple conformations some of which are self-propagating. Such prion-forming proteins have been found in animal, plant, fungal and bacterial species, but have not yet been identified in viruses. Here we report that LEF-10, a baculovirus-encoded protein, behaves as a prion. Full-length LEF-10 or its candidate prion-forming domain (cPrD) can functionally replace the PrD of Sup35, a widely studied prion-forming protein from yeast, displaying a [PSI]-like phenotype. Furthermore, we observe that high multiplicity of infection can induce the conversion of LEF-10 into an aggregated state in virus-infected cells, resulting in the inhibition of viral late gene expression. Our findings extend the knowledge of current prion proteins from cellular organisms to non-cellular life forms and provide evidence to support the hypothesis that prion-forming proteins are a widespread phenomenon in nature.
朊病毒是能够折叠成多种构象的蛋白质，其中一些构象具有自我传播的特性。这种形成朊病毒的蛋白质已在动物、植物、真菌和细菌物种中被发现，但尚未在病毒中被识别。在这里，我们报告说，杆状病毒编码的蛋白 LEF-10 表现为一种朊病毒。全长 LEF-10 或其候选朊病毒形成结构域 (cPrD) 可以功能性地替代酵母中广泛研究的朊病毒形成蛋白 Sup35 的 PrD，表现出类似于 [PSI] 的表型。此外，我们观察到高感染复数可以诱导 LEF-10 在感染病毒的细胞中转化为聚集状态，从而抑制病毒晚期基因的表达。我们的发现将当前朊病毒蛋白的知识从细胞生物扩展到非细胞生命形式，并提供证据支持朊病毒形成蛋白在自然界中广泛存在的假说。
