The hemolymph proteome of fed and starved Drosophila larvae

PLoS One. 2013 Jun 20;8(6):e67208. doi: 10.1371/journal.pone.0067208. Print 2013.

Abstract

The co-operation of specialized organ systems in complex multicellular organisms depends on effective chemical communication. Thus, body fluids (like blood, lymph or intraspinal fluid) contain myriads of signaling mediators apart from metabolites. Moreover, these fluids are also of crucial importance for immune and wound responses. Compositional analyses of human body fluids are therefore of paramount diagnostic importance. Further improving their comprehensiveness should increase our understanding of inter-organ communication. In arthropods, which have trachea for gas exchange and an open circulatory system, the single dominating interstitial fluid is the hemolymph. Accordingly, a detailed analysis of hemolymph composition should provide an especially comprehensive picture of chemical communication and defense in animals. Therefore we used an extensive protein fractionation workflow in combination with a discovery-driven proteomic approach to map out the detectable protein composition of hemolymph isolated from Drosophila larvae. Combined mass spectrometric analysis revealed more than 700 proteins extending far beyond the previously known Drosophila hemolymph proteome. Moreover, by comparing hemolymph isolated from either fed or starved larvae, we provide initial provisional insights concerning compositional changes in response to nutritional state. Storage proteins in particular were observed to be strongly reduced by starvation. Our hemolymph proteome catalog provides a rich basis for data mining, as exemplified by our identification of potential novel cytokines, as well as for future quantitative analyses by targeted proteomics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Proteins / genetics
  • Blood Proteins / metabolism*
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / growth & development
  • Drosophila melanogaster / metabolism*
  • Food Deprivation / physiology
  • Hemolymph / metabolism*
  • Larva / growth & development
  • Larva / metabolism
  • Molecular Sequence Annotation
  • Proteome / genetics
  • Proteome / metabolism

Substances

  • Blood Proteins
  • Drosophila Proteins
  • Proteome

Grant support

This work was supported by grants from SystemsX.ch WingX), the University Research Priority Program Systems Biology/Functional Genomics of the University of Zurich, and the Swiss National Science Foundation. CHA and EB are members of the Quantitative Model Organism Proteomics Initiative, which is funded in part by the University Research Priority Program Systems Biology/Functional Genomics of the University of Zurich. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.