Abstract
Protein fate in higher eukaryotes is controlled by three complexes that share conserved architectural elements: the proteasome, COP9 signalosome, and eukaryotic translation initiation factor 3 (eIF3). Here we reconstitute the 13-subunit human eIF3 in Escherichia coli, revealing its structural core to be the eight subunits with conserved orthologues in the proteasome lid complex and COP9 signalosome. This structural core in eIF3 binds to the small (40S) ribosomal subunit, to translation initiation factors involved in mRNA cap-dependent initiation, and to the hepatitis C viral (HCV) internal ribosome entry site (IRES) RNA. Addition of the remaining eIF3 subunits enables reconstituted eIF3 to assemble intact initiation complexes with the HCV IRES. Negative-stain EM reconstructions of reconstituted eIF3 further reveal how the approximately 400 kDa molecular mass structural core organizes the highly flexible 800 kDa molecular mass eIF3 complex, and mediates translation initiation.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 20473-20478 |
| Number of pages | 6 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Volume | 108 |
| Issue number | 51 |
| DOIs | |
| State | Published - Dec 20 2011 |
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Keywords
- Electron microscopy
- Protein synthesis
- Supramolecular complex assembly
- Translation regulation
ASJC Scopus subject areas
- General
Cite this
Functional reconstitution of human eukaryotic translation initiation factor 3 (eIF3). / Sun, Chaomin; Todorovic, Aleksandar; Querol-Audí, Jordi; Bai, Yun; Villa, Nancy; Snyder, Monica; Ashchyan, John; Lewis, Christopher S.; Hartland, Abbey; Gradia, Scott; Fraser, Christopher S.; Doudna, Jennifer A.; Nogales, Eva; Cate, Jamie H D.
In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 108, No. 51, 20.12.2011, p. 20473-20478.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Functional reconstitution of human eukaryotic translation initiation factor 3 (eIF3)
AU - Sun, Chaomin
AU - Todorovic, Aleksandar
AU - Querol-Audí, Jordi
AU - Bai, Yun
AU - Villa, Nancy
AU - Snyder, Monica
AU - Ashchyan, John
AU - Lewis, Christopher S.
AU - Hartland, Abbey
AU - Gradia, Scott
AU - Fraser, Christopher S.
AU - Doudna, Jennifer A.
AU - Nogales, Eva
AU - Cate, Jamie H D
PY - 2011/12/20
Y1 - 2011/12/20
N2 - Protein fate in higher eukaryotes is controlled by three complexes that share conserved architectural elements: the proteasome, COP9 signalosome, and eukaryotic translation initiation factor 3 (eIF3). Here we reconstitute the 13-subunit human eIF3 in Escherichia coli, revealing its structural core to be the eight subunits with conserved orthologues in the proteasome lid complex and COP9 signalosome. This structural core in eIF3 binds to the small (40S) ribosomal subunit, to translation initiation factors involved in mRNA cap-dependent initiation, and to the hepatitis C viral (HCV) internal ribosome entry site (IRES) RNA. Addition of the remaining eIF3 subunits enables reconstituted eIF3 to assemble intact initiation complexes with the HCV IRES. Negative-stain EM reconstructions of reconstituted eIF3 further reveal how the approximately 400 kDa molecular mass structural core organizes the highly flexible 800 kDa molecular mass eIF3 complex, and mediates translation initiation.
AB - Protein fate in higher eukaryotes is controlled by three complexes that share conserved architectural elements: the proteasome, COP9 signalosome, and eukaryotic translation initiation factor 3 (eIF3). Here we reconstitute the 13-subunit human eIF3 in Escherichia coli, revealing its structural core to be the eight subunits with conserved orthologues in the proteasome lid complex and COP9 signalosome. This structural core in eIF3 binds to the small (40S) ribosomal subunit, to translation initiation factors involved in mRNA cap-dependent initiation, and to the hepatitis C viral (HCV) internal ribosome entry site (IRES) RNA. Addition of the remaining eIF3 subunits enables reconstituted eIF3 to assemble intact initiation complexes with the HCV IRES. Negative-stain EM reconstructions of reconstituted eIF3 further reveal how the approximately 400 kDa molecular mass structural core organizes the highly flexible 800 kDa molecular mass eIF3 complex, and mediates translation initiation.
KW - Electron microscopy
KW - Protein synthesis
KW - Supramolecular complex assembly
KW - Translation regulation
UR - http://www.scopus.com/inward/record.url?scp=84855492118&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84855492118&partnerID=8YFLogxK
U2 - 10.1073/pnas.1116821108
DO - 10.1073/pnas.1116821108
M3 - Article
C2 - 22135459
AN - SCOPUS:84855492118
VL - 108
SP - 20473
EP - 20478
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 51
ER -