Coupling optical tweezers with light microscopy to unravel the mechanobiology of disease

Mechanical forces are at play in a variety of processes relevant to human physiology and disease. For example, every time that we stretch our arm, a number of muscle proteins need to reversibly stretch and recoil under force. Albeit perhaps less conspicuous, a plethora of central cellular functionalities such as differentiation, proliferation, growth, blood pressure sensing, the immune system and senses such as touch or hearing, are all underpinned by mechanical cues. As such, the mechanobiology field-that is, understanding how mechanical forces influence biological systems at the molecular, cellular or tissue level - has witnessed a rapidly explosion in interest in human physiology. Alongside this progress, it has become apparent that disrupted mechanobiology underpins many diseases, from cardiovascular disease to muscular dystrophy and cancer. For example, tumours are often first fingerprinted through palpation as a change in the stiffness of tissue. And yet, we still do not know many molecular mechanosensors, and quite little is still known about the mechanisms by which cells sense extracellular mechanical signals and transduce them into changes in intracellular biochemistry and gene expression - a process known as mechanotransduction. Most of our lack of fundamental understanding on the effects of mechanical forces on the phenotype and function of cells comes from the unavailability of techniques able to directly observe what happens to a cell (or to a protein, a membrane, an organelle or an organoid) upon the application of calibrated mechanical force. Here we propose to purchase a new instrument, exploiting new capabilities that will be unique in the UK and world-wide, that combines optical tweezers with fluorescence microscopy. The instrument will be used as a facility at King's College London, for those groups working on the thriving field of the mechanobiology of disease. Crucially, the instrument will be accessible to ongoing research programmes on the mechanobiology of disease at Queen Mary University, Imperial College London and the MRC Centre for Molecular Bacteriology and Infection, the Francis Crick Institute and the London Centre for Nanotechnology. Collectively, the novel experiments enabled by this unique instrument will provide a first fundamental glimpse on the molecular and cellular mechanisms that determine the onset of a wide variety of diseases, encompassing cardiovascular disease, cancer, nuclear laminopathies, neurodevelopment disorders, inflammation or bacterial infection that nevertheless share a mechanical commonality in their aetiology.

We propose to acquire a recently-launched optical tweezers apparatus combined with a TIRF/IRM/Widefield Fluorescence module (Lumicks C-trap Edge) equipped with the novel Axis Force Detection capability. This instrument enables, for the first time, integration of state-of-the-art nanomechanical experiments (with superior force resolution and stability) with fluorescence imaging capability, providing an unparalleled ability to capture live molecular interactions from a truly innovative perspective that relies on orthogonal, complementary, quantitative read-outs (light and force). This user-friendly instrument will open up new avenues of life science research, by providing new experimental approaches to elucidate the molecular mechanisms by which cells, organoid and tissue react to mechanical forces in health and disease. This unique equipment amalgamates in a single set-up two main research strengths of King's College London- namely mechanobiology and optical microscopy - and researchers working across several institutions in the greater London area whose research interests focus on the mechanobiology of disease. Hence, this equipment will be transformative to the mechanobiology of disease field in the UK, and will be a keystone to foster the UK's international leadership in the research across the Physics of Life in general, and in the mechanobiology field in particular. We request funds to purchase, install and maintain the instrument at King's, which, in support of this strategic application, will contribute with 20% of matching funds.