Murine elongation factor 1 alpha (EF-1 alpha) is posttranslationally modified by novel amide-linked ethanolamine-phosphoglycerol moieties. Addition of ethanolamine-phosphoglycerol to specific glutamic acid residues on EF-1 alpha

Journal Article · Fri Aug 25 00:00:00 EDT 1989 · Journal of Biological Chemistry; (USA)

OSTI ID:5265203

Whiteheart, S W; Shenbagamurthi, P; Chen, L; Cotter, R J; Hart, G W ^[1]

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1. Johns Hopkins Univ. School of Medicine, Baltimore, MD (USA)

Elongation Factor 1 alpha (EF-1 alpha), an important eukaryotic translation factor, transports charged aminoacyl-tRNA from the cytosol to the ribosomes during poly-peptide synthesis. Metabolic radiolabeling with ({sup 3}H) ethanolamine shows that, in all cells examined, EF-1 alpha is the major radiolabeled protein. Radiolabeled EF-1 alpha has an apparent Mr = 53,000 and a basic isoelectric point. It is cytosolic and does not contain N-linked oligosaccharides. Trypsin digestion of murine EF-1 alpha generated two major ({sup 3}H)ethanolamine-labeled peptides. Three peptides were sequenced and were identical to two distinct regions of the human EF-1 alpha protein. Blank sequencing cycles coinciding with glutamic acid in the human cDNA-derived sequence were also found to release ({sup 3}H)ethanolamine, and compositional analysis of these peptides confirmed the presence of glutamic acid. Dansylation analysis demonstrates that the amine group of the ethanolamine is blocked. These results indicate that EF-1 alpha is posttranslationally modified by the covalent attachment of ethanolamine via an amide bond to at least two specific glutamic acid residues (Glu-301 and Glu-374). The hydroxyl group of the attached ethanolamine was shown by mass spectrometry and compositional analysis, to be further modified by the addition of a phosphoglycerol unit. This novel posttranslational modification may represent an important alteration of EF-1 alpha, comparable to the regulatory effects of posttranslational methylation of EF-1 alpha lysine residues.

• OSTI ID: 5265203
• Journal Information: Journal of Biological Chemistry; (USA), Vol. 264:24; ISSN 0021-9258
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
GROWTH FACTORS
POST-TRANSLATION MODIFICATION
PEPTIDES
AMINO ACID SEQUENCE
AMINES
GLUTAMIC ACID
GLYCEROL
HAMSTERS
MAN
MASS SPECTRA
MICE
MOLECULAR WEIGHT
TRACER TECHNIQUES
TRITIUM COMPOUNDS
TRYPSIN
ALCOHOLS
AMINO ACIDS
ANIMALS
CARBOXYLIC ACIDS
ENZYMES
HYDROGEN COMPOUNDS
HYDROLASES
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
MAMMALS
MITOGENS
MOLECULAR STRUCTURE
ORGANIC ACIDS
ORGANIC COMPOUNDS
PEPTIDE HYDROLASES
PRIMATES
PROTEINS
RODENTS
SERINE PROTEINASES
SPECTRA
VERTEBRATES
550201* - Biochemistry- Tracer Techniques