Nonsense-mediated mRNA decay (NMD) is one of the mRNA surveillance mechanisms, which eliminates aberrant mRNAs harboring premature termination codons. NMD targets only mRNAs bound by the nuclear cap-binding protein complex CBP80/20 which directs the pioneer round of translation. Here we demonstrate that NMD occurs efficiently during prolonged hypoxia in which steady-state translation is drastically inhibited. Accordingly, CBP80 remains in the nucleus, and processing bodies are unaffected with regard to their abundance and number under prolonged hypoxic conditions. These results indicate that mRNAs enter the pioneer round of translation during prolonged hypoxia.
Bibliographical noteFunding Information:
We thank Lynne E. Maquat for providing the NMD reporter constructs and α-Upfs antibodies, Robin Reed for α-CBP80 antibody and α-eIF4AIII antibody, John W. Hershey for α-eIF3 antibody, Sung-Gil Chi for α-HIF-1α antibody, Sung Key Jang for α-eIF4GI antibody, and Jens Lykke-Andersen for pCDNA3-FLAG-Dcp1a. This work was supported by a grant of the Korea Health 21 R&D Project, Ministry of Health & Welfare, Republic of Korea (A062356), a Grant (20070301034003) from BioGreen 21 Program, Rural Development Administration, Republic of Korea, and the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea government (MOST) (R01-2006-000-10194-0).
- Eukaryotic translation initiation factor
- Nonsense-mediated mRNA decay
- Nuclear cap-binding protein CBP80/20
- Pioneer round of translation
ASJC Scopus subject areas
- Structural Biology
- Molecular Biology
- Cell Biology