| | |  | | | | Record from Web of Science® | | | | | | |
| The joining of ribosomal subunits in eukaryotes requires eIF5B |
|
|
| Author(s): Pestova TV, Lomakin IB, Lee JH, Choi SK, Dever TE, Hellen CUT |
| Source: NATURE Volume: 403 Issue: 6767 Pages: 332-335 Published: JAN 20 2000 |
| Times Cited: 161 References: 17 |
| Abstract: Initiation of eukaryotic protein synthesis begins with the ribosome separated into its 40S and 60S subunits(1). The 40S subunit first binds eukaryotic initiation factor (eIF) 3 and an eIF2-GTP-initiator transfer RNA ternary complex. The resulting complex requires eIF1, eIF1A, eIF4A, eIF4B and eIF4F to bind to a messenger RNA and to scan to the initiation codon(2). eIF5 stimulates hydrolysis of eIF2-bound GTP and eIF2 is released from the 48S complex formed at the initiation codon before it is joined by a 60S subunit to form an active 80S ribosome(3-8). Here we show that hydrolysis of eIF2-bound GTP induced by eIF5 in 48S complexes is necessary but not sufficient for the subunits to join. A second factor termed eIF5B (relative molecular mass 175,000) is essential for this process. It is a homologue of the prokaryotic initiation factor IF2 (refs 6, 7) and, like it(8-12), mediates joining of subunits and has a ribosome-dependent GTPase activity that is essential for its function. |
| Document Type: Article |
| Language: English |
| Reprint Address: Pestova, TV (reprint author), SUNY Hlth Sci Ctr, Dept Microbiol & Immunol, 450 Clarkson Ave, Brooklyn, NY 11203 USA |
Addresses:
1. SUNY Hlth Sci Ctr, Dept Microbiol & Immunol, Brooklyn, NY 11203 USA
2. Moscow MV Lomonosov State Univ, AN Belozersky Inst Physicochem Biol, Moscow 119899, Russia
3. NICHHD, Lab Eukaryot Gene Regulat, NIH, Bethesda, MD 20892 USA |
| Publisher: MACMILLAN MAGAZINES LTD, PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND |
| Subject Category: Multidisciplinary Sciences |
| IDS Number: 276VU |
| ISSN: 0028-0836 |
|
| | | | | | | | | Record from Web of Science® | | | | | | | | | |