RRC ID |
41602
|
Author |
Shiroki K, Ohsawa C, Sugi N, Wakiyama M, Miura K, Watanabe M, Suzuki Y, Sugano S.
|
Title |
Internal ribosome entry site-mediated translation of Smad5 in vivo: requirement for a nuclear event.
|
Journal |
Nucleic Acids Res
|
Abstract |
Smad5 is thought to relay signals of the bone morphogenetic protein pathway. The 5' untranslated region (5'UTR) of human Smad5 mRNA is long, has the potential to form secondary structures and contains five AUG codons. Here we show that the 5'UTR of Smad5 contains an internal ribosome entry site (IRES) located within 100 nt of the 3' end of the 5'UTR. The Smad5 IRES was 4-8-fold more active than the poliovirus IRES in C2C12 cells, which have osteoblastic differentiation ability, but was 5-10-fold less active than the poliovirus IRES in 293T cells. When an in vitro transcript of a dicistronic Smad5 IRES construct was transfected into C2C12 cells, the Smad5 IRES was not able to stimulate the translation of the downstream cistron, although the cap-dependent translation of the upstream cistron was efficient. In contrast, the poliovirus IRES in a dicistronic in vitro transcript was able to stimulate the translation of the downstream cistron to a similar extent as in the case of transfection of the corresponding dicistronic DNA construct. These results suggest that Smad5 IRES activity displays cell specificity and that some as yet unidentified nuclear event may be required for efficient Smad5 IRES-driven translation initiation.
|
Volume |
30(13)
|
Pages |
2851-61
|
Published |
2002-7-1
|
DOI |
10.1093/nar/gkf408
|
PMID |
12087169
|
PMC |
PMC117063
|
MeSH |
3T3 Cells
5' Untranslated Regions / genetics
5' Untranslated Regions / metabolism
Animals
Binding Sites / genetics
Cell Differentiation
Cell Line
Cell Nucleus / genetics
Cell Nucleus / metabolism
DNA-Binding Proteins / genetics*
Female
HeLa Cells
Humans
Luciferases / genetics
Luciferases / metabolism
Mice
Oocytes
Osteoblasts / cytology
Phosphoproteins / genetics*
Promoter Regions, Genetic / genetics
Protein Biosynthesis
RNA, Messenger / genetics
RNA, Messenger / metabolism
Recombinant Fusion Proteins / genetics
Recombinant Fusion Proteins / metabolism
Ribosomes / metabolism*
Sequence Deletion
Smad5 Protein
Trans-Activators / genetics*
Transcription, Genetic
Xenopus
|
IF |
11.502
|
Times Cited |
25
|
WOS Category
|
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
Resource |
Human and Animal Cells |
ATDC5(RCB0565)
MC3T3-E1(RCB1126) |