Coordination of eukaryotic translation elongation factor 1A (eEF1A) function in actin organization and translation elongation by the guanine nucleotide exchange factor eEF1Balpha.
Eukaryotic translation elongation factor 1A (eEF1A) both shuttles aminoacyl-tRNA (aa-tRNA) to the ribosome and binds and bundles actin. A single domain of eEF1A is proposed to bind actin, aa-tRNA and the guanine nucleotide exchange factor eEF1Balpha. We show that eEF1Balpha has the ability to disrupt eEF1A-induced actin organization. Mutational analysis of eEF1Balpha F163, which binds in this domain, demonstrates effects on growth, eEF1A binding, nucleotide exchange activity, and cell morphology. These phenotypes can be partially restored by an intragenic W130A mutation. Furthermore, the combination of F163A with the lethal K205A mutation restores viability by drastically reducing eEF1Balpha affinity for eEF1A. This also results in a consistent increase in actin bundling and partially corrected morphology. The consequences of the overlapping functions in this eEF1A domain and its unique differences from the bacterial homologs provide a novel function for eEF1Balpha to balance the dual roles in actin bundling and protein synthesis.
Pittman
Yvette R
YR
Department of Molecular Genetics, Microbiology, and Immunology, University of Medicine and Dentistry of New Jersey Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
Kandl
Kimberly
K
Lewis
Marcus
M
Valente
Louis
L
Kinzy
Terri Goss
TG
D000199:Actins / Q000235:genetics / Q000378:metabolism*; D019943:Amino Acid Substitution; D020125:Mutation, Missense; D010441:Peptide Chain Elongation, Translational / Q000502:physiology*; D020648:Peptide Elongation Factor 1 / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary / Q000502:physiology; D012346:RNA, Transfer, Amino Acyl / Q000235:genetics / Q000378:metabolism; D012270:Ribosomes / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
D000199:Actins; D020648:Peptide Elongation Factor 1; D012346:RNA, Transfer, Amino Acyl; D029701:Saccharomyces cerevisiae Proteins