Impact of transgenic oilseed rape expressing oryzacystatin-1 (OC-1) and of insecticidal proteins on longevity and digestive enzymes of the solitary bee Osmia bicornis.
The risk that insect-resistant transgenic plants may pose for solitary bees was assessed by determining longevity of adult Osmia bicornis (O. rufa) chronically exposed to transgenic oilseed rape expressing oryzacystatin-1 (OC-1) or to the purified insecticidal proteins recombinant rOC-1, Kunitz soybean trypsin inhibitor (SBTI), Galanthus nivalis agglutinin (GNA), or Bacillus thuringiensis toxin Cry1Ab dissolved in sugar solution (at 0.01 and 0.1%, w:v, Cry1Ab only at 0.01%). Compared to control bees, longevity was significantly reduced by SBTI and GNA at both concentrations and by rOC-1 at 0.1%, but not by Cry1Ab or rOC-1 at 0.01%. Longevity on the OC-1 oilseed rape was not significantly different from the control plants. The effects of SBTI and rOC-1 on longevity were investigated through characterization of the digestive proteinases of O. bicornis and analysis of the response in proteinase profiles to ingestion of these proteinase inhibitors. A relatively complex profile of at least four types of soluble proteolytic enzymes was identified. Serine proteinases were found to be predominant, with metallo and especially cysteine proteinases making a smaller albeit significant contribution. The compensatory response to in vivo enzyme inhibition was similar for SBTI and rOC-1 although less pronounced for rOC-1. It consisted of a non-specific overproduction of native proteinases, both sensitive and insensitive, and the induction of a novel aspartic proteinase.
Konrad
Roger
R
Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstrasse 191, 8046 Zürich, Switzerland. roger.konrad@art.admin.ch
Connor
Melanie
M
Ferry
Natalie
N
Gatehouse
Angharad M R
AM
Babendreier
Dirk
D
D000704:Analysis of Variance; D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000633:toxicity; D001516:Bees / Q000187:drug effects* / Q000201:enzymology; D001681:Biological Assay; D029741:Brassica rapa / Q000378:metabolism*; D015891:Cystatins / Q000378:metabolism*; D004064:Digestive System / Q000201:enzymology*; D004731:Endotoxins / Q000633:toxicity*; D006460:Hemolysin Proteins / Q000633:toxicity; D008136:Longevity / Q000187:drug effects*; D037241:Mannose-Binding Lectins / Q000633:toxicity; D037121:Plant Lectins / Q000633:toxicity; D030821:Plants, Genetically Modified / Q000378:metabolism*; D014360:Trypsin Inhibitor, Kunitz Soybean / Q000633:toxicity
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D015891:Cystatins; D004731:Endotoxins; D006460:Hemolysin Proteins; D037241:Mannose-Binding Lectins; D037121:Plant Lectins; C030956:insecticidal crystal protein, Bacillus Thuringiensis; C063117:snowdrop lectin; D014360:Trypsin Inhibitor, Kunitz Soybean