Phenotypic and Transcriptomic Analysis of Nicotiana benthamiana Expressing Cucumber mosaic virus 2b gene

Abstract

Cucumber mosaic virus possesses 2b gene known as a suppressor of post-transcriptional gene silencing (PTGS). To investigate its function and effect in plant, transgenic Nicotiana benethamiana expressing 2b gene was developed and analyzed in phenotypic characteristics and differential gene expression (DEG) comparing with wild-type. Eight lines of transgenic plants (T0) were obtained with difficulty and showed severe deformed phenotypes in leaves, flowers, petioles and etc. Moreover, transgenic plants were hardly able to set seeds, but small amounts of seeds were barely produced in some of transgene-hemizygous plants. DEG analysis showed that transgenic plant ectopically accumulated diverse RNA transcripts at higher levels than wild-type probably due to the disturbance in RNA metabolism, especially of RNA decay, caused by 2b-mediated inhibition of PTGS. These ectopic accumulations of RNAs disrupt protein and RNA homeostasis and then subsequently lead to abnormal phenotypes of transgenic plants.

Keywords

• Cucumber mosaic virus (CMV)
• Differential gene expression (DEG)
• Nicotiana benthamiana
• Post-transcriptional gene silencing (PTGS)