Cloning and characterization of SRP1, a suppressor of temperature-sensitive RNA polymerase I mutations, in Saccharomyces cerevisiae.
Cloning and characterization of SRP1, a suppressor of temperature-sensitive RNA polymerase I mutations, in Saccharomyces cerevisiae.
复制标题
酿酒酵母中温度敏感 RNA 聚合酶 I 突变抑制因子 SRP1 的克隆和表征。
DOI：
10.1128/mcb.12.12.5640-5651.1992
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发表时间：
1992
影响因子：
5.3
通讯作者：
Nomura,M
中科院分区：
文献类型：
--
作者：
Yano,R;Oakes,M;Yamaghishi,M;Dodd,JA;Nomura,M
SRP1-1突变是酿酒酵母RNA聚合酶I (Saccharomyces cerevisiae RNA polymerase I, Pol I) A190亚基锌结合域温度敏感突变的等位基因特异性显性抑制基因。我们发现它还抑制Pol IA135亚基的锌结合域的温度敏感突变。该结构域被认为在物理上接近A190锌结合结构域。我们克隆了SRP1基因并确定了其核苷酸序列。该基因编码一个542个氨基酸组成的蛋白质，由三个结构域组成：中心结构域由8个（简并的）42个氨基酸连续串联重复序列组成，以及周围的n端和c端结构域，这两个结构域都含有酸性和碱性氨基酸簇，并且非常亲水。导致这种抑制的突变改变（P219Q）位于中心结构域。利用针对SRP1蛋白的抗体，我们发现SRP1主要定位于细胞核的外围，显然在某些区域更集中，如免疫荧光显微镜点状图所示。我们认为SRP1是与核膜相关的更大的大分子复合物的一个组成部分，并通过含有SRP1的结构中的其他成分直接或间接地与Pol I相互作用。
The SRP1-1 mutation is an allele-specific dominant suppressor of temperature-sensitive mutations in the zinc-binding domain of the A190 subunit of Saccharomyces cerevisiae RNA polymerase I (Pol I). We found that it also suppresses temperature-sensitive mutations in the zinc-binding domain of the Pol IA135 subunit. This domain had been suggested to be in physical proximity to the A190 zinc-binding domain. We have cloned the SRP1 gene and determined its nucleotide sequence. The gene encodes a protein of 542 amino acids consisting of three domains: the central domain, which is composed of eight (degenerate) 42-amino-acid contiguous tandem repeats, and the surrounding N-terminal and C-terminal domains, both of which contain clusters of acidic and basic amino acids and are very hydrophilic. The mutational alteration (P219Q) responsible for the suppression was found to be in the central domain. Using antibody against the SRP1 protein, we have found that SRP1 is mainly localized at the periphery of the nucleus, apparently more concentrated in certain regions, as suggested by a punctate pattern in immunofluorescence microscopy. We suggest that SRP1 is a component of a larger macromolecular complex associated with the nuclear envelope and interacts with Pol I either directly or indirectly through other components in the structure containing SRP1.