Proteomic Analysis of Turnip Crinkle Virus-Infected Tobacco using 2-D Gel Electrophoresis

Abstract

Turnip crinkle virus (TCV) and Nicotiana benthamiana are valuable models to investigate virus-host interaction. The detailed mechanisms of TCV replication and systematic movement in host plants are still not clear. To further understand the processes, two-dimensional electrophoresis (2-DE) coupled with mass spectrometry were used to reveal differentially expressed proteins from isolated protoplasts and chloroplasts of non-infected and TCV-infected N. benthamiana leaves.<br>Fifteen differentially expressed proteins were identified and 8 were up-regulated, while 7 were down-regulated. These proteins were mainly involved in photosynthesis (RuBisCO, RuBisCO activase, chlorophyll a/b binding protein and ferredoxin-NADP reductase), stress response and detoxification (zinc protease, ascorbate peroxidase and heat shock protein 70), energy metabolism (adenylate kinase and ATP synthase), maintenance of pH (chloroplast carbonic anhydrase) and TCV coat protein. Real-time PCR results showed a down-regulation by 62% in TCV-infected N. benthamiana leaves, which confirmed the 2-DE results. <br>In summary, TCV inhibits certain pathways and affects key functions of the plants such as photosynthesis and transcription. Plants resist by increasing protein degradation and detoxification. The 2-DE results of this study have provided us with a more comprehensive picture of plant virus-host interactions and have shed some light on the mechanism of virus infection. (195 words)