SMALL MOLECULES TO TREAT METABOLIC SYNDROME Metabolic Syndrome (MS) is defined as a cluster of inter-related symptoms including central obesity, insulin resistance, dyslipidemia, and hypertension that promote the development of type 2 diabetes mellitus, cardiovascular diseases and certain cancers. In this project a pharmacological strategy will be developed that could alleviate the vicious circle of hyperglycemia (elevated blood glucose) and elevated insulin observed in metabolic syndrome that accelerates the onset of type 2 diabetes. We have identified a new protein that participates in insulin-dependent increase in glucose uptake from the blood. Loss of this protein leads to reduced insulin dependent glucose uptake and a metabolic syndrome like disease in mice. In this project small molecules that modulate the function of the said protein will be developed and evaluated. New molecules that enhance glucose uptake into cells could be potentially powerful new tools to reverse insulin resistance a key pathology of metabolic syndrome that can accelerate the onset of type 2 diabetes.

Touch sensation is built upon the ability of sensory neurons to detect and transduce nanometer scale mechanical displacements. The underlying process has been termed mechanotransduction: the high sensitivity and speed of which is enabled by direct gating (opening) of ion channels by mechanical force. Force detection is functionally compartmentalized and only takes place at the peripheral endings of sensory neurons in vivo. Two molecules are known to be genetically necessary for touch in many sensory neurons, the force gated ion channel PIEZO2 and its modulator STOML3. However, mechanotransduction complexes in all touch receptors absolutely require tethering to the extracellular matrix for function. Tethering is dependent on large extracellular proteins that are sensitive to site-specific proteases. Here we will not only identify the nature of these tethers, but will develop technology to acutely and reversibly abolish tethers and other mechanotransducer components. We will use genome engineering to tag tether and mechanotranduction components in order to visualize and manipulate these proteins at their in vivo sites of action. By engineering de novo cleavage sites for site-specific proteases we will render tethers and ion channels newly sensitive to normally ineffective proteases in the skin. We will engineer mutations into candidate ion channels that dramatically alter biophysical properties to physiologcally “mark” function in vivo. Finally we will develop new behavioural paradigms in mice that allow us to measure touch perception from the forepaw. Psychometric curves for different vibrotactile tasks can then be precisely compared between humans and mice. Furthermore, the impact of acute and reversible manipulation of mechanotransduction on touch perception can be measured. Understanding how molecules assemble to function in a mechanotransduction complex in the skin will open up avenues to develop therapeutic strategies to modulate touch.

According to the latest estimates from the European Cancer Information System, the incidence and mortality from cancer is projected to increase in the next 20 years. Therefore, there is a strong urge to design safe and effective therapeutic approaches to manage cancer progression and ease the burden of the disease. Although the etiology of cancer is highly complex and multifactorial, disruption of the Epidermal Growth Factor Receptor (EGFR) function is commonly associated with the development of several types of cancers. Despite being in the spotlight since its discovery in the late 70’s, several important aspects of EGFR function (e.g oligomerization and receptor bias) still remain largely unexplored. Inspired by this gap of knowledge, the main aim of this proposal is to shed light into the molecular mechanisms governing EGFR oligomerization and signaling. EGFR in dimeric and oligomeric assemblies will be resolved by Cryo-Electron Tomography (Cryo-ET) in near-native conditions. As substantial differences in the transmission of response between dimer and oligomeric EGFR states can arise (receptor bias), these aspects will also be extensively validated/analyzed in vitro. Cryo-ET is revolutionizing the field of structural biology, as proteins can now be resolved without laborious purification protocols which potentially alter structure and function of target proteins. Although promising, this technique is still at early stages of development and only large proteins have been successfully resolved. By resolving the structure of a relatively small and flexible protein, the boundaries of this technique would be expanded and be more applicable for the structural characterization of transmembrane receptors. From the biological point of view, knowing the conditions in which EGFR assemblies are formed and that these assemblies have distinct signal properties, specific therapeutic approaches can be designed to treat cancer minimising the occurrence of side effects.