The overall goal of the research in my lab is to define the molecular mechanisms and functional consequences of cellular mechanotransduction – or how cells sense the mechanical properties of their microenvironment and launch appropriate functional responses. Cell-cell interactions, mediated by adhesion and signaling receptors, are highly dynamic and subject to cytoskeletal movements that impart substantial mechanical force at the interface. How cells combine mechanical and biochemical signals to carry out specific functions is not well understood. Our lab tackles this question in two contexts – the immune response in T cells and regulation of gene expression - using a combination of high (and super)-resolution imaging, force measurements, quantitative image analysis, genomics and mathematical modeling. As part of our NIGMS-funded research, we have recently demonstrated that T cell activation requires a close coordination of the actin and microtubule cytoskeletons in order to generate forces at the T cell receptor, which are transduced to biochemical signaling leading to T cell activation. We have shown that cytokine stimulation leads to modulation of cytoskeletal dynamics and force generation in cytotoxic T cells, facilitating the cytolytic response. We have also developed new methods for analysis of single molecule tracking data, which we have applied to study the dynamics and binding kinetics of transcription factors and relate them to genome-wide measurements. Over the next five years, we plan to continue to address the molecular mechanisms that mediate actin/microtubule crosstalk in T cells for the control of RhoA-mediated forces and how these cytoskeletal forces tune the mechanical coordination of cytotoxic T lymphocyte activation and their efficacy in killing cancer cells. Taking advantage of the flexible nature of the R35 funding mechanism, we will establish a new line of research that builds on our technological capabilities to examine how mechanical cues are relayed to the nucleus to regulate gene expression in a functionally appropriate manner and how mechanical cues interact with tissue-specific cues. We will use advanced tools for real-time visualization of nuclear hormone receptor and target gene transcription dynamics to interrogate 1) how substrate stiffness regulates chromatin accessibility and modulates the mobility of transcription factors and co-activators, with a particular focus on nuclear hormone receptors and 2) how biophysical mechanisms transduce changes in the mechanical environment into alterations in gene expression dynamics. Our research program will 1) elucidate how mechanical stimuli and biochemical signaling are coupled to orchestrate the adaptive immune response and 2) enable fundamental understanding of how mechanical properties of the microenvironment modulate gene expression, with implications for designing new targets for intervention in immune therapy and breast cancer.