真核细胞tRNA的降解

Degradation of Eukaryotic tRNA

tRNA在蛋白质合成过程中起着关键性的作用,不但为三联密码子翻译成氨基酸提供了接合体,而且为将氨基酸运送到核糖体提供了运送载体。在真核细胞中,tRNA前体必须经过广泛的加工修饰,成为成熟的tRNA分子才能充分发挥生物学功能。以往对tRNA的研究主要集中于tRNA的结构、功能、加工和成熟上,却很少关注tRNA分子的降解。最近研究发现tRNA的降解在tRNA的生成、加工和功能发挥上同样起着重要作用。

tRNA molecules play a pivotal role in gene expression by linking mRNA sequence to protein synthesis. Amino acids are brought to the ribosome and transferred to nascent polypeptides with specificity dictated by tRNA. For tRNA to fulfill its functions, mature eukaryotic tRNA must be extensively processed and modified from precursor transcripts. A properly processed tRNA can be aminoacylated in the nucleus, which facilitates its nuclear export. In contrast, unmodified or misfolded tRNA might otherwise interfere with optimal cellular function. Previously, the study of tRNA mostly focused on tRNA structure, maturation and function, but little was known about tRNA degradation. Recent studies showed that the tRNA degradation played an important role in the eukaryotic cell as well as in mRNA degradation.