Tushar Ranjan

By Jitesh Kumar, Khushbu Jain, Priyanka Kumari, Auroshikha Mohanty, Kumari Rajani, Ravi Ranjan Kumar and Tushar Ranjan

In the course of transgenic experiments on the nematode Caenorhabditis elegans, RNA interference, usually abbreviated as RNAi, was discovered first. It is a gene-silencing effect and is found to be widely distributed in eukaryotes. It was observed that control injections of sense RNA were just as effective as antisense RNA, directed at specifically inhibiting target genes in C. elegans by the injection of antisense RNA during an experiment causing the reduction or elimination of expression from the gene under investigation. Subsequently, by injecting double-stranded RNA (dsRNA) corresponding to the target gene, it was discovered that the effect could be most potently elicited, and contamination of the single-stranded RNA (ssRNA; either sense or antisense) by traces of dsRNA could explain the earlier results. By post-transcriptional mechanism, substantial or complete inhibition of expression from any gene can be done using dsRNA corresponding to part or all of the mature mRNA from any given gene. An attempt was made here to describe the basic underlying molecular mechanism of RNAi, the methodology and various experimental requirements, and its advantages and disadvantages. In relation to CRISPR/Cas9 technology, the future prospects of virus-induced gene silencing (VIGS) are considered finally. For the cutting-edge CRISPR/Cas9 genome editing technology, VIGS has emerged as the preferred delivery system besides using it to overexpress or silence genes.

Part of the book: Genetic Transformation in Crops

By Sudhir Kumar, Shampa Purkyastha, Chandan Roy, Tushar Ranjan and Rakesh Deo Ranjan

In the recent past years, global warming and climate change have drastically affected the agricultural crop productivity grown in tropical and subtropical areas globally by appearing to several new biotic and abiotic stresses. Among the abiotic stresses, heat, drought, moisture, and salt stresses are most prevalent. Wheat is the most common and widely used crops due to its economic and social values. Many parts of the world depend on this crop for food and feed, and its productivity is highly vulnerable to these abiotic stresses. Improving tolerance to these abiotic stresses is a very challenging assignment for wheat researchers, and more research is needed to better understand these stresses. The progress made in understanding these abiotic stress tolerances is due to advances in three main research areas: physiology, genetic, and breeding research. The physiology research focused on the alternative physiological and biochemical metabolic pathways that plants use when exposed to abiotic stresses. Identifying genes contributing to particular stress tolerance is very important. New wheat genotypes having a high degree of abiotic stress tolerance are produced through marker-assisted breeding by making crosses from promising concerned stress-tolerant genotypes and selecting among their progeny using gene-specific markers.

Part of the book: Plant Stress Physiology