Detection of seminal fluid proteins in the bed bug,Cimex lectularius, using two-dimensional gel electrophoresis and mass spectrometry

Abstract

SUMMARYThe global increase of the human parasite, the common bed bugCimex lectularius, calls for specific pest control target sites. The bed bug is also a model species for sexual conflict theory which suggests that seminal fluids may be highly diverse. The species has a highly unusual sperm biology and seminal proteins may have unique functions. One-dimensional PAGE gels showed 40–50% band sharing betweenC. lectulariusand another cimicid species,Afrocimex constrictus. However, adult, sexually restedC. lectulariusmales were found to store 5–7 μg of seminal protein and with only 60 μg of protein we obtained informative 2-D PAGE gels. These showed 79% shared protein spots between 2 laboratory populations, and more than half of the shared protein spots were detected in the mated female. Further analysis using liquid chromatography electrospray ionization tandem mass spectrometry revealed that 26·5% of the proteins had matches among arthropods in databases and 14·5% matchedDrosophilaproteins. These included ubiquitous proteins but also those more closely associated with reproduction such asmoj 29, ubiquitin, the stress-related elongation factor EF-1alpha, a protein disulfide isomerase and an antioxidant, Peroxiredoxin 6.