Next Article in Journal
Fusaoctaxin A, an Example of a Two-Step Mechanism for Non-Ribosomal Peptide Assembly and Maturation in Fungi
Next Article in Special Issue
Modification of Vip3Ab1 C-Terminus Confers Broadened Plant Protection from Lepidopteran Pests
Previous Article in Journal
Cannabis: From a Plant That Modulates Feeding Behaviors toward Developing Selective Inhibitors of the Peripheral Endocannabinoid System for the Treatment of Obesity and Metabolic Syndrome
Previous Article in Special Issue
Interactive Effects of [CO2] and Temperature on Plant Chemistry of Transgenic Bt Rice and Population Dynamics of a Non-Target Planthopper, Nilaparvata lugens (Stål) under Different Levels of Soil Nitrogen
Open AccessArticle

Insecticidal Activity of a Vip3Ab1 Chimera Is Conferred by Improved Protein Stability in the Midgut of Spodoptera eridania

Corteva Agriscience, Indianapolis, IN 46268, USA
*
Author to whom correspondence should be addressed.
Present address: Pharmaceutical Biotechnology Center, Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA.
Present address: Pest Control Biologics, Bayer Crop Science, West Sacramento, CA 95605, USA.
§
Present address: Genective Corporation, Weldon, IL 61882, USA.
Toxins 2019, 11(5), 276; https://doi.org/10.3390/toxins11050276
Received: 22 April 2019 / Revised: 8 May 2019 / Accepted: 14 May 2019 / Published: 16 May 2019
Vip3A proteins are important for the control of spodopteran pests in crops, including Spodoptera frugiperda (fall armyworm). Native Vip3Ab1 controls S. frugiperda, but it is ineffective against S. eridania (southern armyworm), a major pest of soybean in South America. Recently, a Vip3Ab1 chimera with a modified C-terminus was described, Vip3Ab1-740, which has increased potency against S. eridania while maintaining activity against S. frugiperda. As S. frugiperda and S. eridania are differentially susceptible to Vip3Ab1, experiments were conducted to identify and understand the mechanism by which this expanded potency is conferred. The role of protein stability, processing, and in vivo effects of Vip3Ab1 and Vip3Ab1-740 in both of these species was investigated. Biochemical characterization of the midgut fluids of these two species indicated no obvious differences in the composition and activity of digestive enzymes, which protease inhibitor studies indicated were likely serine proteases. Histological examination demonstrated that both proteins cause midgut disruption in S. frugiperda, while only Vip3Ab1-740 affects S. eridania. Immunolocalization indicated that both proteins were present in the midgut of S. frugiperda, but only Vip3Ab1-740 was detected in the midgut of S. eridania. We conclude that the gain of toxicity of Vip3Ab1-740 to S. eridania is due to an increase in protein stability in the midgut, which was conferred by C-terminal modification. View Full-Text
Keywords: Vip3A; spodoptera; Bt; Bacillus thuringiensis; insect histopathology; immunolocalization; lepidoptera Vip3A; spodoptera; Bt; Bacillus thuringiensis; insect histopathology; immunolocalization; lepidoptera
Show Figures

Figure 1

MDPI and ACS Style

Bowling, A.J.; Sopko, M.S.; Tan, S.Y.; Larsen, C.M.; Pence, H.E.; Zack, M.D. Insecticidal Activity of a Vip3Ab1 Chimera Is Conferred by Improved Protein Stability in the Midgut of Spodoptera eridania. Toxins 2019, 11, 276.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop