Specialized instruments for single-molecule biology
Our activities mainly focus on interdisciplinary approaches to solve various problems of health and diseases that come under mechanobiology. To solve these problems, we are engaged on but not limited to the following fronts:
Mechanical Roles of Chaperone-assisted Protein Folding Events
Protein folding under force is an integral source of generating mechanical energy in various cellular processes, ranging from protein translation to degradation. Chaperones are specialized proteins known to interact with proteins under mechanical force and regulate their folding. But, how they respond to force and control cellular energetics remains elusive. To address this question, we introduce microfluidic magnetic-tweezers technology to mimic physiological force environment on substrate proteins, keeping the chaperones out of force-influence. Previously we have reported the redox-switchability of E.coli DsbA in the presence of mechanical force. We found chaperones behave differently, while these client proteins are under force than its previously known functions. We have managed to classify the chaperones as foldase (those who favors the folding) and holdase (those who favors the unfolding) and neutral (favors neither), according to their mechanical behavior under force. Further, we are expanding our study to various eukaryotic chaperones that might work under force as well as the bacterial periplasmic chaperones to decipher their mechanism in force-influenced protein-folding
Role of Mechanosensitive Proteins in Focal Adhesion-mediated Cellular Processes
Cell migration is controlled by a force-driven cellular brake system called focal adhesion (FA), a multiprotein assembly of almost 200 proteins. As a well-defined clutch-accelerator system, the proper functioning of FA depends on its constituent mechanical linkages, which both transmit and transduce the mechanical force into the cells. These FA proteins interact mechanically and control the cell migration through traction force. Furthermore, these mutual interactions modulate the force-sensitivity of these proteins, which becomes dysregulated in different pathological conditions. Therefore, it is of utmost importance that what plausible factor can modulate this force-response of these proteins? Since each single protein molecule has its own contribution to the overall FA dynamics and thereby the cell migration, the force-response of a single protein is of prime importance to understanding the underlying mechanism. Single molecule techniques are very handy in knowing their mechanical response and that becomes our strength. Therefore, we study these proteins’ mechanical stability, how their post translational modifications affect it and how protein-protein interactome builds a mechano-regulatory network.
Mechanochemical Signaling in Neurodegenerative Pathologies
The role of mechanotransduction is well known in proper brain functioning; disruption of which causes nerve damage as well as neurodegeneration. But how the mechanical cues are transmitted inside the cell and influence the cellular phenomenons is still elusive. To translate these mechanical cues into chemical signals within the cell, different molecular machines are required. Although a significant amount of research is done on the transport proteins and ion channels, less is known about the role of intracellular mechanosensitive adapter proteins. Kindlin2 is such an important protein related to focal adhesion in the context of brain development as it plays an important role in axonal growth. This protein is expressed in many different types of neurons as well as other brain cells. It is also considered to be one of the main genetic risk factors for the progression of Alzheimer's disease. This protein is an important regulator of many cell signaling modules in various cells and tissues. However, how this protein helps in mechanotransduction through the neurons and other brain cells to maintain overall tissue architecture, is not yet clear at molecular levels. Furthermore, the mechanism of pathogenicity related to this protein and how it affects normal brain activity to trigger neurodegenerative diseases, is also unknown. We employ cutting edge single molecule techniques, computational techniques and other biochemical, molecular techniques to look into these mechanochemical signaling and their role in neurodegeneration.
Role of Small Molecule Drugs and the Micro-environment in Regulating Protein Mechanical Properties
Drug targeting against the mechanosensitive proteins to regulate their mechanosensitivity can be a revolutionary field considering their importance in cancer, autoimmune disorders and other cell adhesion-migration related diseases. Despite the technological advantages, this remains a huge challenge. We employ various techniques to study the effect of already used drugs in mechanical stability of various focal adhesion proteins for the repurposing of these drugs. Furthermore, our cutting edge techniques enable us to study the off-target effects of these drugs on the structural proteins in detail.