期刊
NUCLEIC ACIDS RESEARCH
卷 45, 期 20, 页码 11941-11953出版社
OXFORD UNIV PRESS
DOI: 10.1093/nar/gkx808
关键词
-
资金
- US National Institutes of Health [R01AG042400, R01GM1222814]
- KSU open access fund
- NSF Research Grant [1412250]
- FRQ-S
- KSU
- Innovative Award from Terry Johnson Cancer Center
- JSPS
- KU-COBRE Protein Structure and Function Pilot Grant [P30GM110761]
- Heiwa Nakajima Foundation
- [P20GM103418]
- [55108556]
- Grants-in-Aid for Scientific Research [15K13314] Funding Source: KAKEN
In the human genome, translation initiation from non-AUG codons plays an important role in various gene regulation programs. However, mechanisms regulating the non-AUG initiation rate remain poorly understood. Here, we show that the non-AUG initiation rate is nearly consistent under a fixed nucleotide context in various human and insect cells. Yet, it ranges from <1% to nearly 100% compared to AUG translation, depending on surrounding sequences, including Kozak, and possibly additional nucleotide contexts. Mechanistically, this range of non-AUG initiation is controlled in part, by the elF5-mimic protein (5MP). 5MP represses non-AUG translation by competing with elF5 for the Met-tRNAi-binding factor elF2. Consistently, elF5 increases, whereas 5MP decreases translation of NAT1/EIF4G2/DAP5, whose sole start codon is GUG. By modulating elF5 and 5MP1 expression in combination with ribosome profiling we identified a handful of previously unknown non-AUG initiation sites, some of which serve as the exclusive start codons. If the initiation rate for these codons is low, then an AUG-initiated downstream ORF prevents the generation of shorter, AUG- initiated isoforms. We propose that the homeostasis of the non-AUG translatome is maintained through balanced expression of elF5 and 5MP.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据