Recent Advances on VIGS in Plant Functional Study

In recent decades, availability of ample information of various plant genomes has reached the hand of plant researchers through genome sequencing and expressed sequence tag (EST) analysis that eventually facilitate the functional study of wide range of genes. The previous work on plant functional genomics were exclusively based on forward genetics; that is, identification of a mutant and subsequent cloning of the mutated gene to investigate the wild-type phenotype of target gene. With the advent of the reverse genetics an important alternative approach was to directly alter expression of the gene sequence of interest to be analysed and subsequently identify the mutant phenotype produced after changing their expression. Virus-induced gene silencing (VIGS) has been used extensively with great potential in plant reverse genetics for the past few years. It is the simplicity, quick and cost effectiveness of the method that makes VIGS instrument as an attractive alternative post transcriptional gene silencing (PTGS) method for studying gene function and high-throughput functional genomics. It is used to identify a loss-of-function phenotype of a desire gene involved in basic cellular functions, metabolic pathways, development biology, plant-microbe interaction, and abiotic stress. A. van Kammen first used the term ‘‘VIGS’’ to describe the phenomenon of recovery from virus infection [1].