Potuschak T, Stary S, Schlögelhofer P, Becker F, Nejinskaia V, Bachmair A
Institute of Botany, University of Vienna, Rennweg 14, A-1030 Vienna, Austria.
Proc Natl Acad Sci U S A. 1998 Jul 7;95(14):7904-8. doi: 10.1073/pnas.95.14.7904.
Mutants in the PRT1 gene of Arabidopsis thaliana are impaired in the degradation of a normally short-lived intracellular protein that contains a destabilizing N-terminal residue. Proteins bearing such residues are the substrates of an ubiquitin-dependent proteolytic system called the N-end rule pathway. The chromosomal position of PRT1 was determined, and the PRT1 gene was isolated by map-based cloning. The 45-kDa PRT1 protein contains two RING finger domains and one ZZ domain. No other proteins in databases match these characteristics of PRT1. There is, however, a weak similarity to Rad18p of Saccharomyces cerevisiae. The RING finger domains have been found in a number of other proteins that are involved in ubiquitin conjugation, consistent with the proposed role of PRT1 in the plant N-end rule pathway.
拟南芥PRT1基因的突变体在降解一种正常情况下寿命较短的细胞内蛋白质时出现缺陷，该蛋白质含有一个不稳定的N端残基。带有此类残基的蛋白质是一种名为N端规则途径的泛素依赖性蛋白水解系统的底物。确定了PRT1的染色体位置，并通过图位克隆分离出PRT1基因。45 kDa的PRT1蛋白包含两个环状结构域和一个ZZ结构域。数据库中没有其他蛋白质与PRT1的这些特征相匹配。然而，它与酿酒酵母的Rad18p有微弱的相似性。在许多其他参与泛素缀合的蛋白质中也发现了环状结构域，这与PRT1在植物N端规则途径中的推测作用一致。
