eIF5A Functions Globally in Translation Elongation and Termination

Anthony P Schuller; Colin Chih-Chien Wu; Thomas E Dever; Allen R Buskirk; Rachel Green

doi:10.1016/j.molcel.2017.03.003

eIF5A Functions Globally in Translation Elongation and Termination

Mol Cell. 2017 Apr 20;66(2):194-205.e5. doi: 10.1016/j.molcel.2017.03.003. Epub 2017 Apr 6.

Authors

Anthony P Schuller¹, Colin Chih-Chien Wu¹, Thomas E Dever², Allen R Buskirk¹, Rachel Green³

Affiliations

¹ Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
² Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
³ Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. Electronic address: [email protected].

Abstract

The eukaryotic translation factor eIF5A, originally identified as an initiation factor, was later shown to promote translation elongation of iterated proline sequences. Using a combination of ribosome profiling and in vitro biochemistry, we report a much broader role for eIF5A in elongation and uncover a critical function for eIF5A in termination. Ribosome profiling of an eIF5A-depleted strain reveals a global elongation defect, with abundant ribosomes stalling at many sequences, not limited to proline stretches. Our data also show ribosome accumulation at stop codons and in the 3' UTR, suggesting a global defect in termination in the absence of eIF5A. Using an in vitro reconstituted translation system, we find that eIF5A strongly promotes the translation of the stalling sequences identified by profiling and increases the rate of peptidyl-tRNA hydrolysis more than 17-fold. We conclude that eIF5A functions broadly in elongation and termination, rationalizing its high cellular abundance and essential nature.

Keywords: biochemistry; eIF5A; ribosome profiling; translation elongation; translation termination.

MeSH terms

3' Untranslated Regions
Amino Acid Motifs
Codon, Terminator
Eukaryotic Translation Initiation Factor 5A
Gene Expression Profiling / methods
Hydrolysis
Kinetics
Peptide Chain Elongation, Translational*
Peptide Chain Termination, Translational*
Peptide Initiation Factors / genetics
Peptide Initiation Factors / metabolism*
Peptide Termination Factors / genetics
Peptide Termination Factors / metabolism
Peptides / metabolism
Peptidyl Transferases / genetics
Peptidyl Transferases / metabolism
RNA, Fungal / genetics
RNA, Fungal / metabolism
RNA, Transfer, Amino Acyl / genetics
RNA, Transfer, Amino Acyl / metabolism
RNA-Binding Proteins / genetics
RNA-Binding Proteins / metabolism*
Ribosomes / genetics
Ribosomes / metabolism*
Saccharomyces cerevisiae / genetics
Saccharomyces cerevisiae / metabolism*
Saccharomyces cerevisiae Proteins / genetics
Saccharomyces cerevisiae Proteins / metabolism*

Substances

3' Untranslated Regions
Codon, Terminator
Peptide Initiation Factors
Peptide Termination Factors
Peptides
RNA, Fungal
RNA, Transfer, Amino Acyl
RNA-Binding Proteins
SUP45 protein, S cerevisiae
Saccharomyces cerevisiae Proteins
tRNA, peptidyl-
polyproline
Peptidyl Transferases

Abstract

MeSH terms

Substances

Grants and funding