Aging Results in an Unusual Expression of Drosophila Heat Shock Proteins

• Published in: Proceedings of the National Academy of Sciences - PNAS 1988-06, Vol.85 (11), p.4099-4103
• Main Authors: Fleming, J. E., Walton, J. K., Dubitsky, R., Bensch, K. G.
• Format: Article
• Language: English
• Subjects: 550201 - Biochemistry- Tracer Techniques; Age; AGE DEPENDENCE; Age groups; Ageing, cell death; Aging; AMINO ACIDS; ANIMALS; ARTHROPODS; AUTORADIOGRAPHY; BASIC BIOLOGICAL SCIENCES; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; Biological and medical sciences; BIOLOGY; Canavanine - pharmacology; CARBOXYLIC ACIDS; Cell physiology; Cellular senescence; DAYS LIVING RADIOISOTOPES; DIPTERA; DROSOPHILA; Drosophila melanogaster; Drosophilidae; DRUGS; ELECTROPHORESIS; Electrophoresis, Polyacrylamide Gel; EVEN-ODD NUCLEI; FLIES; FRUIT FLIES; Fundamental and applied biological sciences. Psychology; Gels; GENETICS; Heat shock proteins; Heat shock response; Heat-Shock Proteins - biosynthesis; INSECTS; INVERTEBRATES; Isoelectric Point; ISOTOPES; LIGHT NUCLEI; LIPOTROPIC FACTORS; METHIONINE; Molecular and cellular biology; Molecular Weight; NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC SULFUR COMPOUNDS; PEPTIDES; POLYPEPTIDES; Protein synthesis; PROTEINS; RADIOISOTOPES; Shock heating; SULFUR 35; SULFUR ISOTOPES; TEMPERATURE EFFECTS; TWO-DIMENSIONAL ELECTROPHORESIS
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.85.11.4099

We used high-resolution two-dimensional polyacrylamide gel electrophoresis to evaluate the effect of aging on the heat shock response in Drosophila melanogaster. Although the aging process is not well understood at the molecular level, recent observations suggest that quantitative changes in gene expression occur as these fruit flies approach senescence. Such genetic alterations are in accord with our present data, which clearly show marked differences in the synthesis of heat shock proteins between young and old fruit flies. In 10-day-old flies, a heat shock of 20 min results in the expression of 14 new proteins as detectable by two-dimensional electrophoresis of [35S]methionine-labeled polypeptides, whereas identical treatment of 45-day-old flies leads to the expression of at least 50 new or highly up-regulated proteins. In addition, there is also a concomitant increase in the rate of synthesis of a number of the normal proteins in the older animals. Microdensitometric determinations of the low molecular weight heat shock polypeptides on autoradiographs of five age groups revealed that their maximum expression occurs at 47 days for a population of flies with a mean life span of 33.7 days. Moreover, a heat shock effect similar to that observed in senescent flies occurs in young flies fed canavanine, an arginine analogue, before heat shock.