Pioneer round of translation mediated by nuclear cap-binding proteins CBP80/20 occurs during prolonged hypoxia.
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.
Oh
Nara
N
School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
Kim
Kyoung Mi
KM
Choe
Junho
J
Kim
Yoon Ki
YK
D015687:Cell Hypoxia / Q000235:genetics; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D039502:Nuclear Cap-Binding Protein Complex / Q000032:analysis / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000235:genetics*; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism*
D039502:Nuclear Cap-Binding Protein Complex; D012333:RNA, Messenger