Abstract
Formation of the 30S initiation complex (30S IC) is an important checkpoint in regulation of gene expression. The selection of mRNA, correct start codon, and the initiator fMet-tRNA fMet requires the presence of three initiation factors (IF1, IF2, IF3) of which IF3 and IF1 control the fidelity of the process, while IF2 recruits fMet-tRNA fMet. Here we present a cryo-EM reconstruction of the complete 30S IC, containing mRNA, fMet-tRNA fMet, IF1, IF2, and IF3. In the 30S IC, IF2 contacts IF1, the 30S subunit shoulder, and the CCA end of fMet-tRNA fMet, which occupies a novel P/I position (P/I1). The N-terminal domain of IF3 contacts the tRNA, whereas the C-terminal domain is bound to the platform of the 30S subunit. Binding of initiation factors and fMet-tRNA fMet induces a rotation of the head relative to the body of the 30S subunit, which is likely to prevail through 50S subunit joining until GTP hydrolysis and dissociation of IF2 take place. The structure provides insights into the mechanism of mRNA selection during translation initiation.
| Original language | English (US) |
|---|---|
| Article number | e1001095 |
| Journal | PLoS biology |
| Volume | 9 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 1 2011 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Neuroscience(all)
- Biochemistry, Genetics and Molecular Biology(all)
- Immunology and Microbiology(all)
- Agricultural and Biological Sciences(all)
Cite this
The cryo-EM structure of a complete 30S translation initiation complex from Escherichia coli. / Julián, Patricia; Milon, Pohl; Agirrezabala, Xabier; Lasso, Gorka; Gil, David; Rodnina, Marina V.; Valle, Mikel.
In: PLoS biology, Vol. 9, No. 7, e1001095, 01.07.2011.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The cryo-EM structure of a complete 30S translation initiation complex from Escherichia coli
AU - Julián, Patricia
AU - Milon, Pohl
AU - Agirrezabala, Xabier
AU - Lasso, Gorka
AU - Gil, David
AU - Rodnina, Marina V.
AU - Valle, Mikel
PY - 2011/7/1
Y1 - 2011/7/1
N2 - Formation of the 30S initiation complex (30S IC) is an important checkpoint in regulation of gene expression. The selection of mRNA, correct start codon, and the initiator fMet-tRNA fMet requires the presence of three initiation factors (IF1, IF2, IF3) of which IF3 and IF1 control the fidelity of the process, while IF2 recruits fMet-tRNA fMet. Here we present a cryo-EM reconstruction of the complete 30S IC, containing mRNA, fMet-tRNA fMet, IF1, IF2, and IF3. In the 30S IC, IF2 contacts IF1, the 30S subunit shoulder, and the CCA end of fMet-tRNA fMet, which occupies a novel P/I position (P/I1). The N-terminal domain of IF3 contacts the tRNA, whereas the C-terminal domain is bound to the platform of the 30S subunit. Binding of initiation factors and fMet-tRNA fMet induces a rotation of the head relative to the body of the 30S subunit, which is likely to prevail through 50S subunit joining until GTP hydrolysis and dissociation of IF2 take place. The structure provides insights into the mechanism of mRNA selection during translation initiation.
AB - Formation of the 30S initiation complex (30S IC) is an important checkpoint in regulation of gene expression. The selection of mRNA, correct start codon, and the initiator fMet-tRNA fMet requires the presence of three initiation factors (IF1, IF2, IF3) of which IF3 and IF1 control the fidelity of the process, while IF2 recruits fMet-tRNA fMet. Here we present a cryo-EM reconstruction of the complete 30S IC, containing mRNA, fMet-tRNA fMet, IF1, IF2, and IF3. In the 30S IC, IF2 contacts IF1, the 30S subunit shoulder, and the CCA end of fMet-tRNA fMet, which occupies a novel P/I position (P/I1). The N-terminal domain of IF3 contacts the tRNA, whereas the C-terminal domain is bound to the platform of the 30S subunit. Binding of initiation factors and fMet-tRNA fMet induces a rotation of the head relative to the body of the 30S subunit, which is likely to prevail through 50S subunit joining until GTP hydrolysis and dissociation of IF2 take place. The structure provides insights into the mechanism of mRNA selection during translation initiation.
UR - http://www.scopus.com/inward/record.url?scp=79960917084&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79960917084&partnerID=8YFLogxK
U2 - 10.1371/journal.pbio.1001095
DO - 10.1371/journal.pbio.1001095
M3 - Article
C2 - 21750663
AN - SCOPUS:79960917084
VL - 9
JO - PLoS Biology
JF - PLoS Biology
SN - 1544-9173
IS - 7
M1 - e1001095
ER -