Vitrenko Yakov A, Pavon Mariana E, Stone Stephen I, Liebman Susan W
Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland M/C 567, Chicago, IL 60607, USA.
Curr Genet. 2007 May;51(5):309-19. doi: 10.1007/s00294-007-0127-0. Epub 2007 Apr 6.
Prions are viewed as enigmatic infectious entities whose genetic properties are enciphered solely in an array of self-propagating protein aggregate conformations. Rnq1, a yeast protein with yet unknown function, forms a prion named [PIN+] for its ability to facilitate the de novo induction of another prion, [PSI+]. Here we investigate a set of RNQ1 truncations that were designed to cover major Rnq1 sequence elements similar to those important for the propagation of other yeast prions: a region rich in asparagines and glutamines and several types of oligopeptide repeats. Proteins encoded by these RNQ1 truncations were tested for their ability to (a) join (decorate) pre-existing [PIN+] aggregates made of wild-type Rnq1 and (b) maintain the heritable aggregated state in the absence of wild-type RNQ1. While the possible involvement of particular sequence elements in the propagation of [PIN+] is discussed, the major result is that the efficiency of transmission of [PIN+] from wild-type Rnq1 to a fragment decreased with the fragment's length.
朊病毒被视为神秘的传染性实体，其遗传特性仅编码于一系列自我传播的蛋白质聚集体构象中。Rnq1是一种功能未知的酵母蛋白，因其能够促进另一种朊病毒[PSI+]的从头诱导而形成一种名为[PIN+]的朊病毒。在这里，我们研究了一组Rnq1截短体，其设计目的是覆盖与其他酵母朊病毒传播重要的主要Rnq1序列元件：富含天冬酰胺和谷氨酰胺的区域以及几种类型的寡肽重复序列。测试了由这些Rnq1截短体编码的蛋白质的以下能力：(a) 加入（修饰）由野生型Rnq1构成的预先存在的[PIN+]聚集体，以及 (b) 在没有野生型Rnq1的情况下维持可遗传的聚集状态。虽然讨论了特定序列元件在[PIN+]传播中的可能作用，但主要结果是[PIN+]从野生型Rnq1到片段的传播效率随片段长度的增加而降低。
