Proteomics of immune-challenged Drosophila melanogaster
larvae hemolymph
Sofia de Morais Guedes
a
, Rui Vitorino
a
, Rosa
´
rio Domingues
a
, Kenneth Tomer
b
,
A.J. Ferrer Correia
a
, Francisco Amado
a
, Pedro Domingues
a,
*
a
Department of Chemistry, University of Aveiro, Portugal
b
Laboratory of Structural Biology, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC, USA
Received 14 December 2004
Available online 5 January 2005
Abstract
In the last decade, the fruit fly Drosophila melanogaster has emerged as a promising invertebrate model for the investigation of
innate immunity, in part because of its well characterised genetics. The information provided by the innumerous reports on Dro-
sophilaÕs immune response indicates that a large number of genes, in addition to the well-known antimicrobial peptide genes, are
both up- and down-regulated upon immune challenge. Nevertheless, their contribution to fighting off infection has not been seri-
ously addressed. With the application of recent advances in proteomics, the effects of an immune challenge in the overall modifica-
tion of Drosophila 2-DE protein patterns were investigated. The aim of this study was to investigate hemolymph proteins
differentially expressed between control and immunised larvae sets, which could be related solely to the Drosophila immune
response. The list of immune-related protein spots included heat shock proteins and other proteins with chaperone properties, serine
proteases, phenol oxidase, and Drosophila antioxidant system components, which accounted for 21% of the total of 70 identified
proteins, metabolic enzymes implicated in pathways such as cellular respiration, fatty-acid oxidation, protein biosynthesis, and
structural proteins.
Ó 2005 Elsevier Inc. All rights reserved.
Keywords: Drosophila; Hemolymph larvae; Immune response; MALDI-TOF/TOF
Life on Earth has radiated to fill virtually every con-
ceivable habitat and niche. In each of these, organisms
must interact with their environment and deal with some
degree of variations in its parameters [1]. To some ex-
tent, environmental variations are accommodated with
ease but, beyond certain limits, stress is imposed. This
kind of situation stimulates the organism to undergo
metabolic adjustments that will allow the counteraction
of the stress related negative effects. Studies on the inter-
actions between organisms, their organs and/or cells,
and the changes occurring in the environmental param-
eters cover an enormous part of Modern Biology and
Clinical studies within Medicine [1]. This is easily under-
standable as life is a continuous interplay between envi-
ronmental stimuli and cellular responses.
In the past few years, the subject of innate immunity
has received renewed attention, mainly through studies
involving the model system Drosophila. Not only the
ease of genetic and molecular analysis, combined with
a complete genomic sequence, but also the knowledge
that molecular mechanisms controlling specific biologi-
cal processes are conserved between Drosophila and
mammals makes this organism an essential tool for deci-
phering the biochemical pathways and other compo-
nents of innate immunity. As a result, the
investigations carried out have generated a significant
amount of information focused on the Drosophila
0006-291X/$ - see front matter Ó 2005 Elsevier Inc. All rights reserved.
doi:10.1016/j.bbrc.2004.12.135
*
Corresponding author. Fax: +1 351 234370084.
E-mail address: pedrom@dq.ua.pt (P. Domingues).
www.elsevier.com/locate/ybbrc
Biochemical and Biophysical Research Communications 328 (2005) 106–115
BBRC