Detection of modified Cry4Aa following exposure to cathepsins in the aphid gut.

<p>Aphids were fed overnight, and lumen and membrane fractions from dissected guts were separated by SDS-PAGE and analyzed by western blot for toxin profiles. A second replicate of 57 aphid guts yielded similar results in the lumen fraction. Native Cry4Aa controls: diet—Cry4Aa exposed to aphid diet overnight. Sol, Cry4Aa solubilized in PBS pH 7.4. Tryp, native Cry4Aa exposed to 5% w/w trypsin, (positive control). Nat, native Cry4Aa. Note: none of the controls were exposed to aphid gut proteases. Boxes highlight faint 45 and 20 kDa toxin bands.