Insight into the Salivary Transcriptome and Proteome of Dipetalogaster maxima

Vector Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852, USA.
Journal of Proteome Research (Impact Factor: 4.25). 11/2010; 10(2):669-79. DOI: 10.1021/pr100866h
Source: PubMed


Dipetalogaster maxima is a blood-sucking Hemiptera that inhabits sylvatic areas in Mexico. It usually takes its blood meal from lizards, but following human population growth, it invaded suburban areas, feeding also on humans and domestic animals. Hematophagous insect salivary glands produce potent pharmacologic compounds that counteract host hemostasis, including anticlotting, antiplatelet, and vasodilatory molecules. To obtain further insight into the salivary biochemical and pharmacologic complexity of this insect, a cDNA library from its salivary glands was randomly sequenced. Salivary proteins were also submitted to one- and two-dimensional gel electrophoresis (1DE and 2DE) followed by mass spectrometry analysis. We present the analysis of a set of 2728 cDNA sequences, 1375 of which coded for proteins of a putative secretory nature. The saliva 2DE proteome displayed approximately 150 spots. The mass spectrometry analysis revealed mainly lipocalins, pallidipins, antigen 5-like proteins, and apyrases. The redundancy of sequence identification of saliva-secreted proteins suggests that proteins are present in multiple isoforms or derive from gene duplications.

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    • "To discover unique pharmacologically active agents, salivary components of triatomine bugs have been explored in Rhodnius prolixus (Ribeiro et al., 2004), Triatoma brasiliensis (Santos et al., 2007), Triatoma infestans (Assumpção et al., 2008), Triatoma dimidiata (Kato et al., 2010) and Dipetalogaster maxima (Assumpção et al., 2011) by transcriptome analyses of the salivary gland. Characteristically, their salivary components were found to be rich in lipocalins, a large group of extracellular proteins that bind and transport small hydrophobic molecules. "
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