CRISPR-Cas for genome editing: Classification, mechanism, designing and applications

Clustered regularly interspersed short pallindromic repeats (CRISPR) and CRISPR associated proteins (Cas) system (CRISPR-Cas) came into light as prokaryotic defence mechanism for adaptive immune response. CRISPR-Cas works by integrating short sequences of the target genome (spacers) into the CRISPR locus. The locus containing spacers interspersed repeats is further expressed into small guide CRISPR RNA (crRNA) which is then deployed by the Cas proteins to evade the target genome. Based on the Cas proteins CRISPR-Cas is classified according to polythetic system of classification. The characteristic of the CRISPR-Cas9 system to target DNA sequences using programmable RNAs has opened new arenas due to which today CRISPR-Cas has evolved as cutting end technique in the field of genome editing. Here, we discuss about the evolution of CRISPR, its clas-sification and various Cas systems including the designing and molecular mechanism of CRISPR-Cas. Applica-tions of CRISPR-Cas as a genome editing tools are also highlighted in the areas such as agriculture, and anticancer therapy. Briefly discuss the role of CRISPR and its Cas systems in the diagnosis of COVID-19 and its possible preventive measures. The challenges in existing CRISP-Cas technologies and their potential solutions are also discussed briefly.

Automated summary

The CRISPR-Cas system is an adaptive immune response mechanism in prokaryotes that integrates short sequences of the target genome (spacers) into the CRISPR locus. CRISPR-Cas, classified based on Cas proteins, uses programmable RNAs to target DNA sequences and has become a powerful technique in genome editing. This article discusses the evolution, classification, design, and molecular mechanism of CRISPR-Cas systems, as well as their applications in agriculture and anticancer therapy. It also briefly explores the role of CRISPR and its Cas systems in the diagnosis and prevention of COVID-19, and discusses the challenges and potential solutions in existing CRISPR-Cas technologies.