RNA interference (RNAi) has progressed swiftly in the past decade to become a convenient and dominant genetic tool that has immense utility in diverse fields. The entomological research, ranging from functional genomics to agriculture, has gained enormous momentum due to this technology. RNAi tool helped to discover the functions of new genes and study the complicated genetic networks, thus providing an evolutionary insight into various processes. RNAi is also becoming a method of choice for controlling insect pest populations. It is envisaged as tailor-made insecticide, which is highly species specific. However, the efficiency of this mechanism is limited by various factors such as the stability of the trigger molecule, the candidate gene selection, delivery system adopted and, most importantly, the choice of the target species. Apart from the successful implication in diverse areas, there are certain drawbacks of this technology such as ‘off-target’ effects, lack of sensitivity of various species, etc. Further research would relieve these limitations and support the manifestation of this genetic tool with much more reliability.
Part of the book: RNA Interference
The next-generation sequencing (NGS) technologies embrace advance sequencing technologies that can generate high-throughput RNA-seq data to delve into all the possible aspects of the transcriptome. It involves short-read sequencing approaches like 454, illumina, SOLiD and Ion Torrent, and more advance single-molecule long-read sequencing approaches including PacBio and nano-pore sequencing. Together with the help of computational approaches, these technologies are revealing the necessity of complex non-coding part of the genome, once dubbed as “junk DNA.” The ease in availability of high-throughput RNA-seq data has allowed the genome-wide identification of long non-coding RNA (lncRNA). The high-confidence lncRNAs can be filtered from the set of whole RNA-seq data using the computational pipeline. These can be categorized into intergenic, intronic, sense, antisense, and bidirectional lncRNAs with respect to their genomic localization. The transcription of lncRNAs in plants is carried out by plant-specific RNA polymerase IV and V in addition to RNA polymerase II and target the epigenetic regulation through RNA-directed DNA methylation (RdDM). lncRNAs regulate the gene expression through a variety of mechanism including target mimicry, histone modification, chromosome looping, etc. The differential expression pattern of lncRNA during developmental processes and different stress responses indicated their diverse role in plants.
Part of the book: Next Generation Plant Breeding