转移RNA
生物
主要组织相容性复合体
MHC I级
翻译(生物学)
蛋白质生物合成
真核翻译
抗原呈递
遗传学
起始因子
细胞生物学
核糖核酸
信使核糖核酸
免疫系统
基因
T细胞
作者
Shelley R. Starck,Changying Jiang,Mariana Pavon-Eternod,Sharanya Prasad,Brian P. McCarthy,Tao Pan,Nilabh Shastri
出处
期刊:Science
[American Association for the Advancement of Science (AAAS)]
日期:2012-06-29
卷期号:336 (6089): 1719-1723
被引量:202
标识
DOI:10.1126/science.1220270
摘要
Effective immune surveillance by cytotoxic T cells requires newly synthesized polypeptides for presentation by major histocompatibility complex (MHC) class I molecules. These polypeptides are produced not only from conventional AUG-initiated, but also from cryptic non-AUG-initiated, reading frames by distinct translational mechanisms. Biochemical analysis of ribosomal initiation complexes at CUG versus AUG initiation codons revealed that cells use an elongator leucine-bound transfer RNA (Leu-tRNA) to initiate translation at cryptic CUG start codons. CUG/Leu-tRNA initiation was independent of the canonical initiator tRNA (AUG/Met-tRNA(i)(Met)) pathway but required expression of eukaryotic initiation factor 2A. Thus, a tRNA-based translation initiation mechanism allows non-AUG-initiated protein synthesis and supplies peptides for presentation by MHC class I molecules.
科研通智能强力驱动
Strongly Powered by AbleSci AI