Translation initiation factor a/eIF2(-gamma) counteracts 5' to 3' mRNA decay in the archaeon Sulfolobus solfataricus.
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ABSTRACT:
SUBMITTER: Hasenohrl D
PROVIDER: S-EPMC2538890 | biostudies-other | 2008 Feb
REPOSITORIES: biostudies-other
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Translation initiation factor a/eIF2(-gamma) counteracts 5' to 3' mRNA decay in the archaeon Sulfolobus solfataricus.
Hasenöhrl David D Lombo Tania T Kaberdin Vladimir V Londei Paola P Bläsi Udo U
Proceedings of the National Academy of Sciences of the United States of America 20080201 6
The trimeric translation initiation factor a/eIF2 of the crenarchaeon Sulfolobus solfataricus is pivotal for binding of initiator tRNA to the ribosome. Here, we present in vitro and in vivo evidence that the a/eIF2 gamma-subunit exhibits an additional function with resemblance to the eukaryotic cap-complex. It binds to the 5'-triphosphate end of mRNA and protects the 5' part from degradation. This unprecedented capacity of the archaeal initiation factor further indicates that 5' --> 3' direction ...[more]
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