Effects of increased lifespan on chromatin condensation in the adult male housefly

Abstract

Analysis of the chromatin condensation pattern in optic lobe nuclei from the adult male housefly has shown significant differences in males from a long lived, low activity (LA) group as compared to a short lived, high activity (HA) group. The rate of chromatin condensation in the LA group was very much less than that observed in the HA group, leaving the nuclei from the former group in a permanently lowered condensation state. Moreover, a detailed comparison of the amount and spatial distribution of a single high density chromatin component (HDC) suggests that the low activity conditions not only lowers the rate of chromatin condensation but also alters the normal program controlling this process. Linear discriminant analysis showed that a consistently higher percentage of nuclei from the LA group, as compared to the HA group, could be classified with a 1-day-old model derived from the HA group. These results are discussed with respect to environmental influences on lifespan and are compared to the response of lipofuscin accumulation in low activity male houseflies.