Translation initiation factor a/eIF2(-gamma) counteracts 5' to 3' mRNA decay in the archaeon Sulfolobus solfataricus.
نویسندگان
چکیده
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' directional mRNA decay is a pathway common to all domains of life.
منابع مشابه
The archaeal eIF2 homologue: functional properties of an ancient translation initiation factor
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 105 6 شماره
صفحات -
تاریخ انتشار 2008