[Frontiers in Bioscience E4, 1780-1786, January 1, 2012]

Proteomic analysis of peach fruit moth larvae treated with phosphine

Tao Liu1, Li Li1, Baishu Li1, Fanhua Zhang1,Yuejin Wang1

1Chinese Academy of Inspection and Quarantine, NO.241, Huixinxijie, Chaoyang district, Beijing, 100029, P.R. China

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Materials and methods
3.1. Preparation of test insects
3.2. Phosphine treatment
3.3. Sample preparation
3.4. 2-DE and protein identification
3.5. Enzyme activity assays
4. Results
4.1. Phosphine toxicity on the peach fruit moth
4.2. Differential proteomic profiles of the peach fruit moth in response to phosphine treatment
4.3. Enzyme activity analysis
5. Discussion
6. Acknowledgments
7. References

1. ABSTRACT

Phosphine has been used worldwide for the control of stored-product insects for many years. However, the molecular mechanism of its toxicity is not clearly understood. In the current study, larvae of the peach fruit moth were fumigated with phosphine. Proteomic analysis was then performed to identify the regulated proteins. Our results confirmed the phosphine toxicity on the peach fruit moth. The median lethal time LT50 was 38.5 h at 330 ppm at 25 °C. During fumigation, the respiration of the peach fruit moth was extremely inhibited. Of the 26 regulated proteins, 16 were identified by MALDI-TOF mass spectrometry after a 24 h treatment. The proteins were classified as related to metabolism (25%), anti-oxidation (6%), signal transduction (38%), or defense (19%). The rest (13%) were unclassified. Phosphine regulation of ATP and glutathione contents, as well as of ATP synthase and glutathione S-transferase 2 activities were confirmed by enzyme activity analysis. These results demonstrate that complex transcriptional regulations underlie phosphine fumigation. New theories on the mechanism of phosphine toxicity may also be established based on these results.