Immunity and defense in pea aphids, Acyrthosiphon pisum

Authors: GERARDO, N - Emory University; ALTINCICEK, B - University Of Giessen; ANSELME, C - University Of Lyon; ATAMIAN, H - University Of California; BARRIBEAU, S - Emory University; DE VOS, M - Boyce Thompson Institute; DUNCAN, E - University Of Otago; Evans, Jay; GABALDON, T - Center For Genomic Regulation (CRG); GHANIM, M - Volcani Center (ARO); HEDDI, A - University Of Lyon; KALOSHIAN, I - University Of California; LATORRE, A - University Of Valencia; MONEGAT, C - University Of Lyon; MOYA, A - University Of Valencia; NAKABACHI, A - Riken Institute; PARKER, B - Emory University; PEREZ-BROCAL, V - University Of Lyon; PIGNATELLI, M - University Of Valencia; RAHBE, Y - University Of Lyon; RAMSEY, J - Boyce Thompson Institute; SPRAGG, C - Emory University; TAMAMES, J - University Of Valencia; TAMARIT, D - University Of Valencia; TAMBORINDEGUY, C - Cornell University; VILCINSKAS, A - University Of Giessen

Submitted to: Genome Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2009
Publication Date: 2/15/2010
Citation: Gerardo, N.M., Altincicek, B., Anselme, C., Atamian, H., Barribeau, S.M., De Vos, M., Duncan, E.J., Evans, J.D., Gabaldon, T., Ghanim, M., Heddi, A., Kaloshian, I., Latorre, A., Monegat, C., Moya, A., Nakabachi, A., Parker, B.J., Perez-Brocal, V., Pignatelli, M., Rahbe, Y., Ramsey, J., Spragg, C., Tamames, J., Tamarit, D., Tamborindeguy, C., Vilcinskas, A. 2010. Immunity and defense in pea aphids, Acyrthosiphon pisum. Genome Biology. 11:R21.

Interpretive Summary: Insects can have both deleterious and beneficial impacts on agriculture. Unlike honey bees and other pollinators herbivorous insects like aphids can have a severe negative impact on crop production. This study describes the methods aphids use to fight off disease, and contrasts those results with results found for honey bees and other insects. Like honey bees, the pea aphid lacks many immune genes found in other insects. This suggests particular sensitivities to pathogens. Information on insect immune genes can be used to improve breeding and management of beneficial species and to determine potential weak points in the defenses of insects that are deleterious to agriculture. Researchers will use this information to develop rational tools for controlling aphids and the viruses they carry to plants.

Technical Abstract: Recent genomic analyses of arthropod defense mechanisms suggest conservation of key elements underlying responses to pathogens, parasites, and stresses. At the center of pathogen-induced immune response are signaling pathways triggered by the recognition of fungal, bacterial, and viral signatures. These pathways result in the production of response molecules, such as antimicrobial peptides and lysozymes, which degrade or destroy invaders. The purpose of this study was to characterize the immune and stress gene repertoire of the pea aphid (Acyrthosiphon pisum), a distant relative of previously characterized insects. Strikingly, pea aphids appear to be missing genes thought critical for recognition, signaling, and microbial degradation in insects. In line with results of gene annotation, experimental analyses designed to characterize immune response through the isolation of RNA transcripts and proteins from immune-challenged pea aphids uncovered few immune-related products. Gene expression studies, however, indicated some differential expression of immune and stress-related genes upon challenge. The absence of genes thought critical to the insect immune response in the pea aphid suggests that the traditional view of insect immunity may not be as broadly applicable as once thought. The limitations of the aphid immune system may be representative of a broad range of insects, or may be aphid specific. We suggest that several aspects of the aphid life style could facilitate survival without strong immune protection.