Research

Life Sciences & Biotechnology

Title :

Elucidating the Interplay between Ligand-Binding and DNA-Recognition in the Transcription Regulator CytR

Area of research :

Life Sciences & Biotechnology

Principal Investigator :

Dr. Athi Narayanan Naganathan, Indian Institute Of Technology (IIT) Madras, Tamil Nadu

Timeline Start Year :

2023

Timeline End Year :

2026

Contact info :

Details

Executive Summary :

CytR, or cytidine repressor, is a crucial transcription regulator in E. coli's energy metabolism, particularly under stressed conditions. It regulates gene expression, maltose utilization, and heat-shock response, and is also involved in the pathogenicity of V. cholerae by controlling chitinase synthesis and flagellation. CytR interacts with multiple promoter regions, specifically the uniquely disordered DNA binding domain (DBD), which can bind to inverted sequence repeats with multiple central spacers ranging from 0 to 11 bp. However, little is known about the structural-mechanistic features that govern the functional-thermodynamic landscape of CytR. The cytidine binding signal to the ligand-binding domain (LBD) is allosterically transduced to the DBD to regulate binding. There needs to be a pre-equilibrium between open and closed conformations in the LBD for precise and controlled cytidine binding. Mutations can be engineered into CytR LBD to alter the DNA binding affinity in a rational manner. Understanding these questions would shed insights into the mechanisms underlying expression regulation and energy metabolism in E. coli. To explore these questions, a detailed functional and thermodynamic characterization of CytR LBD and the full-length CytR will be performed using spectroscopic, calorimetric, and HDX MS studies. Mutations will then be introduced to systematically tune the binding affinity to cytidine and the downstream DNA binding response.

Total Budget (INR):

49,17,000

Organizations involved