Genetic and environmental factors affecting the de novo appearance of the [PSI+] prion in Saccharomyces cerevisiae.
Genetic and environmental factors affecting the de novo appearance of the [PSI+] prion in Saccharomyces cerevisiae.
复制标题
影响酿酒酵母中[PSI]朊病毒从头出现的遗传和环境因素。
DOI：
10.1093/genetics/147.2.507
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发表时间：
1997
期刊：
影响因子：
3.3
通讯作者：
Liebman,SW
中科院分区：
文献类型：
--
作者：
Derkatch,IL;Bradley,ME;Zhou,P;Chernoff,YO;Liebman,SW
以前已经证明酵母普里昂[PSI+]可以被盐酸铵治愈，尽管关于固化的可逆性的报道是相互矛盾的。在这里，我们表明，GuHCl处理[psi+]和[psi-]酵母菌株都会产生两类[psi-]衍生物：Pin+，其中[Psi+]可以被Sup35p的过量生产重新诱导；Pin-，其中完整的SUP35基因的过度表达不会导致[Psi+]的出现。然而，在Pin+和Pin-衍生物中，[PSI+]是由于过量生产短的Sup35P N-末端片段而重新诱导的，因此，原则上，[PSI+]固化在这两种情况下都是可逆的。在Pin-[psi-]衍生物中未观察到SUP35过表达对细胞生长的抑制或抑制作用。遗传分析表明，Pin+表型是由一个非孟德尔因子决定的，与[PSI+]Prion不同，它独立于Sup35p的N-末端结构域。热休克蛋白Hsp104的瞬时失活也产生了Pin-[psi-]衍生物，而Hsp104过量生产固化的[Psi+]只产生Pin+[psi-]衍生物。我们假设，除了Sup35p N-末端的[PSI+]Prion决定结构域外，在Sup35p的C-近端还有另一个自传播的构象决定因素，并且这个第二个Prion与Pin+表型有关。
It has previously been shown that yeast prion[PSI+]is cured by GuHCl, although reports on reversibility of curing were contradictory. Here we show that GuHCl treatment of both[PSI+]and[psi–]yeast strains results in two classes of[psi–]derivatives: Pin+, in which[PSI+]can be reinduced by Sup35p overproduction, and Pin–, in which overexpression of the completeSUP35gene does not lead to the[PSI+]appearance. However, in both Pin+and Pin–derivatives[PSI+]is reinduced by overproduction of a short Sup35p N-terminal fragment, thus, in principle,[PSI+]curing remains reversible in both cases. Neither suppression nor growth inhibition caused bySUP35overexpression in Pin+[psi–]derivatives are observed in Pin–[psi–]derivatives. Genetic analyses show that the Pin+phenotype is determined by a non-Mendelian factor, which, unlike the[PSI+]prion, is independent of the Sup35p N-terminal domain. A Pin–[psi–]derivative was also generated by transient inactivation of the heat shock protein, Hsp104, while[PSI+]curing by Hsp104 overproduction resulted exclusively in Pin+[psi–]derivatives. We hypothesize that in addition to the[PSI+]prion-determining domain in the Sup35p N-terminus, there is another self-propagating conformational determinant in the C-proximal part of Sup35p and that this second prion is responsible for the Pin+phenotype.