Chiu Y H, Morris N R
Department of Microbiology and Molecular Genetics, Rutgers-The State University of New Jersey, New Brunswick 08901, USA.
Genetics. 1997 Mar;145(3):707-14. doi: 10.1093/genetics/145.3.707.
NudC encodes a protein of unknown biochemical function that is required for nuclear migration. In an attempt to define its function by identifying interacting proteins, a screen for extragenic suppressors of the temperature-sensitive nudC3 mutation was undertaken that identified nine snc genes. Here we demonstrate that nudC3 has a missense mutation at amino acid 146 that causes leucine to be replaced by proline and that sncB69 encodes a mutant tRNA(Leu) that corrects the mutation. The sncB69 mutation deletes a single nucleotide in the anticodon of a tRNA(Leu) that changes its normal 5'CAG3' leucine anticodon to the proline anticodon 5'CCG3', which presumably allows incorporation of leucine at the mutant nudC3 proline codon 146 and thereby causes suppression of the nudC3 mutant phenotype.
NudC编码一种生化功能未知的蛋白质，该蛋白质是核迁移所必需的。为了通过鉴定相互作用蛋白来确定其功能，我们对温度敏感型nudC3突变的基因外抑制子进行了筛选，鉴定出9个snc基因。在这里，我们证明nudC3在氨基酸146处有一个错义突变，导致亮氨酸被脯氨酸取代，并且sncB69编码一种突变的tRNA（Leu），可校正该突变。sncB69突变删除了tRNA（Leu）反密码子中的一个单核苷酸，使其正常的5'CAG3'亮氨酸反密码子变为脯氨酸反密码子5'CCG3'，这可能使得亮氨酸能够在突变的nudC3脯氨酸密码子146处掺入，从而导致nudC3突变体表型的抑制。
