Life Sciences & Biotechnology
Title : | Unravelling the Functional Mechanism of Target Recognition and Cleavage in an Unusual CRISPR-Cas System |
Area of research : | Life Sciences & Biotechnology |
Principal Investigator : | Prof. B Anand, Indian Institute Of Technology (IIT) Guwahati, Assam |
Timeline Start Year : | 2023 |
Timeline End Year : | 2026 |
Contact info : | banand@iitg.ac.in |
Details
Executive Summary : | The CRISPR-Cas system is an RNA-guided defense mechanism that provides adaptive immunity to bacteria and archaea against phage infection. The immune response is functionalized through three stages: adaptation, maturation, and interference. This project aims to understand the functional adaptations of CRISPR machinery in a newly discovered type I-G CRISPR-Cas system. During CRISPR interference, the recognition of target DNA/RNA and its subsequent elimination form the climax of successful genome defence. Two essential components of CRISPR machinery are essential in type I systems: a ribonucleoprotein (RNP) surveillance complex and an effector Cas nuclease. In the newly identified type I-G CRISPR variant, the subunits of the RNP complex, such as Cas5 and Cas6, are fused to form a single subunit. These genetic rearrangements are likely to alter the composition and architecture of the RNP surveillance complex and its ability to recognize the target nucleic acid. The effector nuclease that cleaves the target displays a reversal of domain order in type I-G, raising questions about how the specificity of target DNA recognition by RNP surveillance complex and the subsequent cleavage by Cas3 are influenced by these domain rearrangements.
To address this question, researchers have cloned the subunits of RNP surveillance complex and Cas3, reconstituted the RNP complex in vivo, and addressed protein-protein and protein-nucleic acid interactions using biochemical and biophysical experiments. Physiologically relevant hypothesis will be tested using molecular genetics experiments using Escherichia coli as a surrogate host. These approaches are expected to uncover deep insights into how changes in structural architecture of CRISPR machinery lead to functional adaptations in type I-G CRISPR-Cas system. |
Total Budget (INR): | 59,08,760 |
Organizations involved