Protein synthesis elongation factor EF-1 alpha expression and longevity in Drosophila melanogaster.
It has been proposed that the decline in protein synthesis observed in aging organisms may result from a decrease in elongation factor EF-1 alpha. Transgenic Drosophila melanogaster flies carrying an additional copy of the EF-1 alpha gene under control of a heat-inducible promoter have an extended lifespan, further indicating that the EF-1 alpha gene may play an important role in determining longevity. To test this hypothesis, we have quantitated EF-1 alpha mRNA, EF-1 alpha protein, and the EF-1 alpha complex-formation activity in these transgenic flies. Furthermore, we have tested whether the transgene construct is functional--i.e., whether transgenic mRNA is induced when flies are grown at higher temperature. The results show that although there is a clear difference in mean lifespan between the EF-1 alpha transgenic (E) flies and the control transgenic (C) flies, E flies do not express more EF-1 alpha protein or mRNA than C flies kept at the same experimental conditions. Although the transgene can be induced when E flies are heat-shocked at 37 degrees C, transgenic mRNA is not detectable in E flies aged at 29 degrees C. In both lines, the loss in catalytic activity with age is the same. We conclude that the E flies examined here do not live longer because of overexpressing the EF-1 alpha gene.
Shikama
N
N
Department of Cell Biology, University of Basel, Switzerland.
Ackermann
R
R
Brack
C
C
D000818:Animals; D030801:Animals, Genetically Modified; D015152:Blotting, Northern; D004331:Drosophila melanogaster / Q000254:growth & development* / Q000378:metabolism; D015870:Gene Expression; D006207:Half-Life; D006360:Heat-Shock Proteins / Q000235:genetics; D008136:Longevity; D008297:Male; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D015183:Restriction Mapping; D014158:Transcription, Genetic
D006360:Heat-Shock Proteins; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors; D012333:RNA, Messenger