MRNA EXPORT FROM THE NUCLEUS OF SACCHAROMYCES CEREVISIAE

目标是表征可用的温度敏感突变体， 酿酒酵母（amn突变体），其在酵母细胞中积累polyA+ mRNA。 原子核温度为37 ℃。 这些突变体分为11个互补组。 在确定polyA+ RNA积累的程度后， 37 ℃时mRNA的积累和周转率，上位性 三种表型可区分的amn类型之间的关系 突变体，蛋白质在37 °输入到细胞核的程度，以及 将研究核膜在37 °时的形态学变化。 利用野生型和amn细胞在37 °下， 然后将表征平均mRNA的末端，沿着评估 剪接和正常剪接的前体mRNA的命运。 此外，将确定mRNA的核内定位，并将一组 将鉴定与核内mRNA相关的蛋白质。 进一步的研究将监测tRNA和rRNA的合成和命运， 37度 与此同时，负责Ts病变的基因将被克隆， 通过互补和测序， AMN基因的过度表达将被研究，AMN转录本将被 并针对相应的基因产生抗血清 产品. 抗血清将用于定位AMN基因产物， 来研究它们的生物合成和周转。

The goal is to characterize available temperature-sensitive mutants of Saccharomyces cerevisiae (amn mutants) which accumulate polyA+ mRNA in the nucleus at 37oC. These mutants fall into eleven complementation groups. After determining the extent of polyA+ RNA accumulation, the reversibility of mRNA accumulation, and the rate of turnover of mRNA at 37o, epistatic relations among three phenotypically-distinguishable classes of amn mutants, the extent of protein import into the nucleus at 37o, and morphological alterations of the nuclear envelope at 37o will be studied. Using wild type and amn cells at 37o, the structure of the 5' and 3' terminae of average mRNA will then be characterized, along with assessment of splicing and the fate of a pre-mRNA which normally is spliced. Moreover, mRNA intranuclear location will be determined and the set of proteins with which intranuclear mRNA is associated will be identified. Further studies will monitor the synthesis and fate of tRNA and rRNAs at 37o. In parallel, the genes responsible for the Ts- lesions will be cloned by complementation and sequenced, the consequences of under and overexpression of AMN genes will be studied, AMN transcripts will be characterized and antisera will be raised against the corresponding gene products. The antisera will be used to localize the AMN gene products and to study their biosynthesis and turnover.