CuZn-SOD promoter-driven expression in the Drosophila central nervous system

The aim of this study was to ascertain the status of CuZn superoxide dismut ase (CuZn-SOD) expression in the central nervous system of Drosophila melan ogaster. Immunoblot analysis of dissected tissue extracts revealed low leve ls of the CuZn-SOD protein in adult brains relative to other adult and larv al tissues. To explore further this observation, three different reporter c onstructs containing different elements of the CuZn-SOD promoter domain wer e used for the generation of transgenic flies. A high level of reporter gen e expression occurred during the second wave of neurogenesis (third instar and early pupal stages) in scattered, proliferating neuroblasts (NBs) and i n proliferation centers of the optic lobe. In mature, postmitotic neurons, this expression was lower relative to other tissues. In adult flies, at all ages examined, there was little if any detectable reporter gene expression in cells of the central nervous system. These results suggest that one of the key components of the antioxidant defenses, CuZn-SOD, is quite low in p ostmitotic neural tissue, rendering it particularly susceptible to oxidativ e damage during aging. (C) 1999 Elsevier Science Inc. All rights reserved.