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Genome-wide Mapping of Protein-DNA Interactions with ChEC-seq in Saccharomyces cerevisiae
Published on: June 3, 2017
Saccharomyces cerevisiae protein Pci8p and human protein eIF3e/Int-6 interact with the eIF3 core complex by binding
A Shalev1, L Valásek, C A Pise-Masison
1Laboratory of Gene Regulation and Development, NICHD, and the Basic Research Laboratory, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA.
The Journal of Biological Chemistry
|July 18, 2001
Summary
Researchers identified a new protein, Pci8p, in yeast that interacts with the eukaryotic initiation factor-3 (eIF3) complex. While Pci8p is structurally similar to human eIF3e/Int-6, its deletion did not affect cell growth or translation, suggesting a role in transcriptional regulation.
Area of Science:
- Molecular Biology
- Cell Biology
- Genetics
Background:
- Eukaryotic initiation factor-3 (eIF3) is crucial for protein translation initiation.
- The eIF3e/Int-6 protein is found in various eukaryotes but absent in Saccharomyces cerevisiae.
- Int-6 is implicated in transcriptional control, making its homologs potential regulators of gene expression.
Purpose of the Study:
- To characterize a novel Saccharomyces cerevisiae protein, Pci8p, containing a conserved PCI domain.
- To investigate the interaction of Pci8p and human eIF3e/Int-6 with the yeast eIF3 complex.
- To explore the functional significance of Pci8p in translation initiation and transcriptional regulation.
Main Methods:
- Protein expression and purification in yeast.
- In vivo and in vitro interaction assays (co-immunoprecipitation).
- Polysome analysis to assess translation initiation.
- Oligonucleotide microarray analysis to study mRNA expression profiles.
Main Results:
- Pci8p and human eIF3e/Int-6 bind to the yeast eIF3 subunit Prt1p.
- Human eIF3e/Int-6 interacts with a homologous region on human Prt1p.
- Deletion of PCI8 did not affect cell growth or translation initiation.
- Deletion of PCI8 led to reduced mRNA levels for specific heat shock proteins.
Conclusions:
- Pci8p is structurally and functionally similar to human eIF3e/Int-6 in its interaction with the eIF3 complex.
- Pci8p is not essential for the core function of eIF3 in translation initiation in S. cerevisiae.
- Pci8p may play a role in the transcriptional control of specific genes, such as heat shock proteins, suggesting dual roles in transcription and translation.
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