title: Cultured Aedes albopictus mosquito cells accumulate elongation factor-1 alpha (EF-1 alpha) during serum starvation.
abstract: We examined survival, growth and protein synthesis in mosquito cells that had been maintained for up to 21 days in serum-free medium. On polyacrylamide gels, protein bands from "starved" cells remained discrete, and despite low levels of incorporation, radiolabeled bands were detectable, suggesting that low levels of protein synthesis were sustained. A prominent band that accumulated in serum-starved cells was digested with trypsin and analyzed by tandem mass spectrometry, which identified the protein as eukaryotic elongation factor (EF)-1 alpha EF-1 alpha is well-conserved among species, and differential accumulation of EF-1 alpha in serum-starved cells was verified by western blotting using a primary antibody to the homologous protein from Trypanosoma brucei. Aside from its importance in the elongation step of protein synthesis, EF-1 alpha has been shown to have a number of non-canonical functions, including interaction with viral RNA and a potential role in apoptosis. We anticipate that the prolonged viability of mosquito cells in serum-free medium may provide a system to explore whether EF-1 alpha accumulation is an adaptive response compatible with resumption of growth in the event that nutrients are replenished, or whether the excess EF-1 alpha represents an irreversible commitment to an apoptotic pathway.
authors.affiliation: Department of Entomology, University of Minnesota, St. Paul, USA.
authors.forename: Melinda Sue
authors.initials: MS
authors.lastname: Schwientek
authors.forename: LeeAnn
authors.initials: L
authors.lastname: Higgins
authors.forename: Ann Marie
authors.initials: AM
authors.lastname: Fallon
mesh_terms: D000330:Aedes / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D002452:Cell Count; D002470:Cell Survival; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D019476:Insect Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D020648:Peptide Elongation Factor 1 / Q000378:metabolism*; D013997:Time Factors
chemical_list: D016895:Culture Media, Serum-Free; D019476:Insect Proteins; D020648:Peptide Elongation Factor 1