CRISPR/Cas-Based Techniques in Plants

CRISPR techniques have been used in plants and animals with equal success. Ever since the emergence of CRISPR technology, scientists have been trying to find new CRISPR tools to address the concerns associated with the use of this technology. So, with the advent of time, new CRISPR tools have been discovered which are more precise and have broad spectrum with less limitations. The CRISPR toolbox has a number of tools for targeted modifications at epigenetic, genetic, transcriptional, and posttranscriptional level. For epigenetic modifications, dCas9 (catalytically dead Cas9) can be fused with Kruppel-associated box (KRAB), LSD1, acetyltransferase, DNA methyltransferase, DNA demethylase and some other effector domains. For targeted modifications at genomic level, Cas9 can be fused with different effector domains such as FokI, nickases, recombinases, transposases etc. For modifications at posttranscriptional level, Cas13 and CRISPRi approaches have been used successfully. CRISPR techniques are tremendous and have broad-spectrum applications compared to previous genome editing tools: ZFNs (zinc finger nucleases) and TALENs (Transcription activator like effector nucleases). Modularity of CRISPR technology has made it a technology of choice for the researchers and scientists all over the world. In this chapter, an overview of the CRISPR techniques has been given with details of their applications for different purposes.