Contributions of protein aggregation to gene regulation and phenotypic diversity

摘要 蛋白质的聚集与人类疾病密切相关，包括数十种 家族性和年龄相关疾病，共同构成了一个主要的新兴健康威胁， 我们的老百姓然而，最近的发现表明，蛋白质聚集也可以 具有广泛的结构和调节功能。的广泛性和普遍性 这种非病理性聚集在很大程度上是未被探索的。在芽殖酵母中， 酿酒酵母，多种内在无序蛋白（IDP），包括转录因子，RNA- 结合蛋白和激酶在生理条件下具有聚集的趋势。 一种这样的蛋白质，转录因子Mot3，是已知的少数蛋白质之一， 形成自我繁殖的聚集体，作为基于蛋白质的遗传元件，或朊病毒。 Mot3通过在聚集状态之间切换，拓宽了表型的范围 克隆酵母菌群。这项工作的目标是1）制定一个定量的 流式细胞术报告IDP的细胞内聚集，2）研究结果 3）测试这些机构的汇总情况， 蛋白质，特别是Mot3，是一种适应性生物过程。这项工作将促进我们的 了解非病理性蛋白质聚集，同时建立一个平台，为未来 询问活细胞中的功能性和疾病相关聚集。

ABSTRACT The aggregation of proteins is deeply associated with human diseases, including dozens of familial and age-associated disorders that together comprise a major emerging health threat to our aging populace. However, recent discoveries indicate that protein aggregation can also have a wide range of structural and regulatory functions. The breadth and pervasiveness of such non-pathological aggregation is largely unexplored. In the budding yeast, Saccharomyces cerevisiae, multiple intrinsically disordered proteins (IDPs), including transcription factors, RNA- binding proteins, and kinases, have a tendency to aggregate under physiological conditions. One such protein, the transcription factor Mot3, is one of only a handful of proteins known to form self-propagating aggregates that act as protein-based elements of inheritance, or prions. By switching to and from its aggregated state, Mot3 broadens the range of phenotypes accessible to clonal yeast populations. The goals of this work are to 1) develop a quantitative flow cytometric reporter for intracellular aggregation by IDPs, 2) investigate the consequences of aggregation on the regulatory activities of IDPs, and 3) test whether aggregation by these proteins, and by Mot3 in particular, is an adaptive biological process. This work will advance our understanding of non-pathological protein aggregation, while establishing a platform for future interrogations of both functional and disease-associated aggregation in living cells.