Different response to infection in Drosophila melanogaster, Ceratitis capitata, and Tenebrio molitor.

PÉREZ M.M.; SCHACHTER J. AND QUESADA-ALLUÉ L.A*.

DROSOPHILA INFORMATION SERVICE

University of Oklahoma-USA

Lugar: Norman, Oklahoma, USA; Año: 2006 vol. 89

0070-7333

We previously were able to measure, for the first time, the activity of NBAD synthase in the epidermis of the Medfly, Ceratitis capitata . This enzyme conjugates dopamine with b-alanine, and in vitro shows a broad substrate activity. It is induced by 20-OH-ecdysone at the time of molting but, as expected, is not active during intermolt periods . In contrast, we recently demonstrated that, surprisingly, NBAD also is present in neural tissue, but in a constitutive manner (Pérez et al., 2004). In order to explore the possibility of NBAD synthase induction due to bacterial challenge we used D. melanogaster and C. capitata adults as well as T. molitor larvae V. In the absence of bacteria no NBAD was synthesized  whereas, infected insects contained [14C]-labeled substances that behaved as NBAD. Induction of NBAD synthase was tested in T. molitor larvae, as well as in C. capitata and D. melanogaster adults by injection of live E. coli or 0.1 mg/ml E. coli lipopolysaccharides (LPS) in T. molitor and D. melanogaster. This peculiar NBAD synthase induction, presumably associated to the innate immune response seems to be absent in D. melanogaster. However, induction in T. molitor do occurs , thus indicating that probably this is a response widely present in insects.