Identification of Partners of Tif34, a Component of the Yeast Eif3 Complex, Required for Cell Proliferation and Translation Initiation
Resource
THE EMBO JOURNAL v.16 n.22 pp.6812-6822
Journal
THE EMBO JOURNAL
Journal Volume
v.16
Journal Issue
n.22
Pages
6812-6822
Date Issued
1997
Date
1997
Author(s)
VERLHAC, MARIE-HELENE
CHEN, RUEY-HWA
HANACHI PARISA
HERSHEY JOHN W B
DERYNCK RIK
Abstract
Eukaryotic initiation factor-3 (eIF3) in the yeast saccharomyces cerevisiae plays a central role in initiation of translation. The eIF3 complex contains at least eight different proteins, but, as yet, little is kniwn about the function of the individual proteins. In this study we have characterized the role of TIF34 (eLF3-p39), a recently identified WD- 40 domain-containing protein of 39 kDa, in the eIF3 complex. Using temperature-sensitive mutants of TIF34 we show that this protein is required for cell cycle progression and for mating and plays an essential role in initiation of protein synthesis. By two-hybrid screening we have identified two partmers that directly associate with TIF34: PRT1, a previously characterized eIF3 subunit, and a nocel protein of 33 kDa (eIF3 ) which is part of the eIF3 complex and has an RNA binding domain. TIF34 and p33 interact with eavh other and overexpression of p33 complements the growth defect of a tif34-ts mutant. Our results provide support for both physical and functional interactions between three subunits, TIF34, Prt1 and p33, in the eIF3 complex.