Decreased lifespan in the absence of expression of the mitochondrial small heat shock protein Hsp22 in Drosophila.
Aging is a well regulated biological process involving oxidative stress and macromolecular damages. Three main pathways have been shown to influence lifespan, the insulin/insulin-like growth factor-1 pathway, the silent regulator pathway, and the target of rapamycin pathway. Among many proteins influencing lifespan, two transcription factors, FOXO and the heat shock factor, have been shown to be involved in the aging process and in small heat shock proteins (sHsps) expression following stress and during lifespan. We have recently shown that overexpressing the mitochondrial Hsp22 increases Drosophila melanogaster lifespan by 32% and resistance to oxidative stress. Here we show that flies that are not expressing this mitochondrial small Hsp22 have a 40% decrease in lifespan. These flies die faster than their matched control and display a decrease of 30% in locomotor activity compared with controls. The absence of Hsp22 also sensitizes flies to mild stress. These data support a key role of sHsps in aging and underline the importance of mitochondrial sHsps in this process.
Laboratoire de Génétique Cellulaire et Développementale, Département de Médecine, CREFSIP, Pavillon CE-Marchand, Université Laval, Ste-Foy, Québec G1K 7P4, Canada.
Geneviève
G
Morrow
Sophie
S
Battistini
Ping
P
Zhang
Robert M
RM
Tanguay
D000818:Animals; D029721:Drosophila Proteins / Q000172:deficiency / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development*; D017353:Gene Deletion; D006360:Heat-Shock Proteins / Q000172:deficiency / Q000235:genetics*; D008136:Longevity / Q000235:genetics*; D008928:Mitochondria / Q000235:genetics / Q000502:physiology*; D009043:Motor Activity; D009068:Movement; D018384:Oxidative Stress / Q000502:physiology*
D029721:Drosophila Proteins; D006360:Heat-Shock Proteins; C490752:Hsp22 protein, Drosophila