Rhee S K, Icho T, Wickner R B
Section on Genetics of Simple Eukaryotes, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892.
Yeast. 1989 May-Jun;5(3):149-58. doi: 10.1002/yea.320050304.
The yeast chromosomal genes SKI2, SKI3, SKI4, SKI6, SKI7 and SKI8 repress the replication of double-stranded RNA viruses, protecting the host from the otherwise lethal effects of the virus. We cloned and sequenced the SKI3 gene and found that it encodes a 163 kDa protein including a typical nuclear localization signal. Cell fractionation experiments show that the SKI3 gene product is indeed tightly associated with nuclei and that the putative nuclear localization sequence directs beta-galactosidase into the nucleus. However, fusion of a part of the SKI3 protein lacking this signal with beta-galactosidase also directs beta-galactosidase into the nucleus, suggesting the presence of a second nuclear localization signal. The SKI3 gene is only essential in the presence of an M double-stranded RNA virus.
酵母染色体基因SKI2、SKI3、SKI4、SKI6、SKI7和SKI8可抑制双链RNA病毒的复制，保护宿主免受病毒致命影响。我们克隆并测序了SKI3基因，发现它编码一种163 kDa的蛋白质，其中包含一个典型的核定位信号。细胞分级分离实验表明，SKI3基因产物确实与细胞核紧密相关，且推测的核定位序列可将β-半乳糖苷酶导入细胞核。然而，将缺乏该信号的部分SKI3蛋白与β-半乳糖苷酶融合，也能将β-半乳糖苷酶导入细胞核，这表明存在第二个核定位信号。SKI3基因仅在存在M双链RNA病毒时才是必需的。
