Ter-Avanesyan M D, Kushnirov V V, Dagkesamanskaya A R, Didichenko S A, Chernoff Y O, Inge-Vechtomov S G, Smirnov V N
Institute of Experimental Cardiology, Cardiology Research Centre, Moscow, Russia.
Mol Microbiol. 1993 Mar;7(5):683-92. doi: 10.1111/j.1365-2958.1993.tb01159.x.
SUP35 is an omnipotent suppressor gene of Saccharomyces cerevisiae coding for a protein consisting of a C-terminal part similar to the elongation factor EF-1 alpha and a unique N-terminal sequence of 253 amino acids. Twelve truncated versions of the SUP35 gene were generated by the deletion of fragments internal to the coding sequence. Functional studies of these deletion mutants showed that: (i) only the EF-1 alpha-like C-terminal part of the Sup35 protein is essential for the cell viability; (ii) overexpression of either the N-terminal part of the Sup35 protein or the full-length Sup35 protein decreases translational fidelity, resulting in omnipotent suppression and reduced growth of [psi+] strains; (iii) expression of the C-terminal part of the Sup35 protein generates an antisuppressor phenotype; and (iv) both the N- or C-terminal segments of the Sup35 protein can bind to 80S ribosomes. Thus, the data obtained define two domains within the Sup35 protein which are responsible for different functions.
SUP35是酿酒酵母的一种全能抑制基因，编码一种蛋白质，该蛋白质由一个与延伸因子EF-1α相似的C末端部分和一个由253个氨基酸组成的独特N末端序列组成。通过缺失编码序列内部的片段，产生了12个SUP35基因的截短版本。对这些缺失突变体的功能研究表明：（i）只有Sup35蛋白的EF-1α样C末端部分对细胞活力至关重要；（ii）Sup35蛋白的N末端部分或全长Sup35蛋白的过表达会降低翻译保真度，导致全能抑制并降低[psi+]菌株的生长；（iii）Sup35蛋白C末端部分的表达产生反抑制表型；（iv）Sup35蛋白的N末端或C末端片段都能与80S核糖体结合。因此，所获得的数据定义了Sup35蛋白中负责不同功能的两个结构域。
