Publish Your Research Online
Get Recognition - International Audience
Request for an Author Account | Login | Submit Article
|HOME||FAQ||TOP AUTHORS||FORUMS||PUBLISH ARTICLE|
Virus Induced Gene Silencing (VIGS) for Functional Genomics of Crop PlantsBY: Dr. Basavaprabhu L. Patil | Category: Genetics | Submitted: 2014-04-22 06:56:38
Article Summary: "In the past, plant scientists mostly relied upon forward genetics; which involved identification of a mutant and subsequent cloning of the mutated gene to identify the gene responsible for the function/trait under investigation. During the last several years, Arabidopsis, rice, tomato, cassava, pigeon pea, chick pea and other pl.."
Virus Induced Gene Silencing (VIGS) for Functional Genomics of Crop Plants
Authors: Basavaprabhu L. Patil*, Monika Dalal, Rohini Sreevathsa, Subodh Kumar Sinha
In the past, plant scientists mostly relied upon forward genetics; which involved identification of a mutant and subsequent cloning of the mutated gene to identify the gene responsible for the function/trait under investigation. During the last several years, Arabidopsis, rice, tomato, cassava, pigeon pea, chick pea and other plant genomes have been sequenced and large data base of sequence information has been generated. Such genome and EST sequencing projects have generated a wealth of sequence information for important plant species of which the majority is difficult to subject to functional genomics. Thus alternative approaches to traditional forward genetics need to be employed to identify the genes responsible for a trait or a function. An important alternative approach is reverse genetics, which investigates the function of a gene by altering the expression of the gene of interest and then identifying the mutant phenotype that is produced. Most reverse genetics approaches described in plants to date rely on posttranscriptional gene silencing (PTGS) or RNA interference (RNAi). Knocking out of genes is the most commonly used strategy of reverse genetics to know the gene functions. Two most common examples of insertional mutagenesis approaches, predominantly used in Arabidopsis are: transferred DNA (T-DNA) and transposon tagging. Although these are robust tools for providing mutants, they have some limitations, such as difficulty in studying the function of duplicated genes in the case of multigene families, the difficulty to reach genome saturation, and the multiple insertional nature of these strategies, which frequently lead to simultaneous knock down of multiple genes, thus making it difficult to identify the correct gene.
Virus-induced gene silencing (VIGS) is a technology that exploits an RNA-mediated (RNAi) antiviral defense mechanism and has been shown to be of great potential in plant reverse genetics or the functional genomics. The term "VIGS" was coined by van Kammen in 1997, to describe the phenomenon of recovery from virus infection. However, the term has since been applied almost exclusively to the technique involving recombinant viruses to knock-down expression of endogenous genes. The discovery of PTGS of endogenous genes by recombinant viruses carrying an identical sequence was made in 1995 and immediately the potential of VIGS as a tool for the analysis of gene function was quickly recognized. Circumvention of plant genetic transformation, methodological simplicity, robustness, and speedy results makes VIGS an attractive alternative approach in plant functional genomics. Thus VIGS provides a powerful tool to facilitate gene functional studies for plant species which are recalcitrant for genetic transformation. Recent approaches allow the use of VIGS as a high throughput method that will exploit the potential of genome and transcriptome projects further. Since the discovery of VIGS, it has been widely employed to characterize the plant genes involved in cellular functions, metabolic pathways, plant-microbe, plant-nematode and plant-insect interaction. In addition to the biotic stresses, several abiotic stresses like drought, salinity, temperature, water are major constraints limiting crop production across the globe. VIGS has also been employed to identify genes for nutrient biofortification in crop plants.
Tobacco mosaic virus (TMV) was the first RNA virus to be used as a silencing vector in 1995 and later in 2001, the limitations of host range and meristem exclusion were overcome with development of VIGS vectors based on Tobacco rattle virus (TRV). One of the more interesting developments to improve the VIGS technology is use of bipartite Cabbage leaf curl virus (CbLCV) in Arabidopsis by Turnage et al. (2002). Lack of appropriate VIGS vectors with broad host range is a major limitation and to facilitate this, VIGS vectors with broad host range have been developed by employing Tobacco rattle virus (TRV) and Apple latent spherical virus (ASLV) vectors. VIGS vectors that produce severe symptoms in host plants should be avoided to have proper visualization of the plant phenotype exhibited by gene/s under investigation. Lack of silencing in certain tissues, uneven or localized silencing is another concern of VIGS and for this reporter gene (GFP) expression along with expression of VIGS vectors should be useful for visualizing the silenced tissues. To prevent low silencing efficiency, insert should be in range of 200-350 bp, localized expression of a viral silencing suppressor improves virus multiplication and off-target silencing by VIGS vectors should be taken care off. Over the years, improved methods for VIGS vector delivery into plants, namely agro-drench, toothpick inoculation and viral sap inoculation have been developed and the availability of such methods has facilitated large-scale screening of plant genes. This also has helped in customized application of VIGS to meet the specific requirements of plant biologists. Thus VIGS as a reverse genetics tool for studies on plant functional genomics presents several advantages, promises rapid generation of functional genomics and even proteomics. With the progress in whole genome sequencing of many important crop plants, VIGS approach will be widely and popularly used.
• Lange M, Yellina AL, Orashakova S, Becker A. (2013) Virus-induced gene silencing (VIGS) in plants: an overview of target species and the virus-derived vector systems. Methods Mol Biol. 975:1-14.
• Senthil-Kumar M, Mysore KS. (2011) New dimensions for VIGS in plant functional genomics. Trends Plant Sci. 16(12):656-65.
• Purkayastha A, Dasgupta I. (2009) Virus-induced gene silencing: a versatile tool for discovery of gene functions in plants. Plant Physiol Biochem. 47(11-12):967-76.
• Robertson D. (2004) VIGS vectors for gene silencing: many targets, many tools. Annu Rev Plant Biol. 55:495-519.
• Burch-Smith TM, Anderson JC, Martin GB, Dinesh-Kumar SP. (2004) Applications and advantages of virus-induced gene silencing for gene function studies in plants. Plant J. 39(5):734-46.
• Lu R, Martin-Hernandez AM, Peart JR, Malcuit I, Baulcombe DC. (2003) Virus-induced gene silencing in plants. Methods. 30(4):296-303.
About Author / Additional Info:
Corresponding author e-mail: firstname.lastname@example.org
Comments on this article: (0 comments so far)
• Seed Production of Carrot
• Potential Health Benefits of Chia
• Multiple Peptide Signals and Their Interplay in Growth and Defense
• The Impact of Biomass in Sustainable Development Today
Latest Articles in "Genetics" category:
• The Science and History of Genetics. How It Predicts the Genetic Code
• Telomeres: Is It Responsible For Ageing and Cancer?
• Human Genetic Engineering,its Methods and Ethics
• Gene Mutation And Cancer
• DNA Technology Used in Forensics
• DNA Fingerprinting: Uses and Methods Involved
• Treatment of Genetic Diseases by Gene Therapy
• Human Intelligence and Genetics
• Ethical Issues Related to Human and Animal Cloning
• Mitochondrial DNA and Forensic
• DNA Footprinting and Gene Sequencing
• Biotechnology and Types of Cloning
• Designer Babies:Method and Ethical Issues
• Prenatal Diagnosis: Non-invasive and Invasive Techniques
• What are the Benefits of Genetic Engineering?
• The Advantages and Disadvantages of Genetic Engineering in Humans
• Types of Genetic Disorders
• Bovine Somatotropin: A Growth Hormone
• Advantages and Disadvantages of Genetically Modified Food
Important Disclaimer: All articles on this website are for general information only and is not a professional or experts advice. We do not own any responsibility for correctness or authenticity of the information presented in this article, or any loss or injury resulting from it. We do not endorse these articles, we are neither affiliated with the authors of these articles nor responsible for their content. Please see our disclaimer section for complete terms.
Copyright © 2010 biotecharticles.com - Do not copy articles from this website.
ARTICLE CATEGORIES :
| Disclaimer/Privacy/TOS | Submission Guidelines | Contact Us