Phosphoglycerylethanolamine Posttranslational Modification of Plant Eukaryotic Elongation Factor 1α1

Abstract

Eukaryotic elongation factor 1␣ (eEF-1A

Phosphatidylethanolamine Is the Precursor of the Ethanolamine Phosphoglycerol Moiety Bound to Eukaryotic Elongation Factor 1A

“…This modification occurs at, or near, the site of PE synthesis and temporarily renders eEF1A membrane-bound. Interestingly, plant eEF1A has been reported to incorporate 14 C-labeled fatty acids, however, no direct evidence was provided that eEF1A was modified with an entire PE molecule (11 (49), showed no incorporation of radioactivity into eEF1A (results not shown). However, this is not surprising, because we were unable to detect a PE-modified form of eEF1A by mass spectrometry, and, thus, this form may represent a minor fraction of total eEF1A only.…”

“…2). In particular, the two glutamate residues shown to be modified with EPG in plant, Glu 289 and Glu 362 (11), and mammalian eEF1A, Glu 301 and Glu 374 (9,10), are conserved in T. brucei eEF1A (Glu 289 and Glu 362 ). The original identification of EPG bound to eEFA1 in mammalian cells was prompted by the observation that eEF1A was labeled with [ 3 H]Etn (9, 10).…”

“…1). Subsequently, the same modification was found in plant (11), but not yeast (12), eEF1A. The discovery of the EPG modification was prompted by the observation that a 49-kDa cytosolic protein was labeled after incubation of mammalian cells in culture with tritiated ethanolamine (Etn) (9,10), an approach that was originally aimed at identifying glycosylphosphatidylinositol (GPI)-anchored proteins.…”

The Potyviral P3 Protein Targets Eukaryotic Elongation Factor 1A to Promote the Unfolded Protein Response and Viral Pathogenesis

“…For example, the addition of a phosphatidylethanolamine (PE) moiety can affect the activity of eEF1A (Hiatt et al, 1982;Whiteheart et al, 1989;Rosenberry et al, 1989;Venema et al, 1991;Ransom et al, 1998;Zobel-Thropp et al, 2000). Indeed, all the five GmEF1A isoforms contain two PE binding sites that are highly conserved in plant eEF1A proteins but have not been reported in the yeast EF1A.…”

Calcium-Regulated Proteolysis of eEF1A

“…eEF1A fractionates with the endoplasmic reticulum (Hayashi et al, 1989), cytoskeleton (Yang et al, 1990;Tan and Boss, 1992;Durso and Cyr, 1994;Shiina et al, 1994;Ransom et al, 1998), and plasma membranes (Ransom et al, 1998). There are several lines of evidence indicating that the function and distribution of eEF1A are sensitive to changes in cytosolic pH (Condeelis, 1995;Liu et al, 1996a).…”