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We focus on distinct cellular structures that mediate cell adhesion and contractility. Cell-matrix and cell-cell junctions and the actomyosin cytoskeleton are responsible for the dynamic control of cell and tissue shape during development and homeostasis and their mis-regulation is associated with various diseases.

Collaborating with experts in single molecule imaging, mass-spectrometry, and bioinformatics, and specializing ourselves in genetics and live-cell imaging, we are taking a multi-scale approach – from single proteins to a whole organism – to address the following mechanobiological questions:​

Research overview

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The decreasing cost of whole genome sequencing and the push toward personalized medicine is driving an exponential growth in the number of human patients who have their genomes sequenced. As a result, more than 80 million variations in the genome, including single nucleotide polymorphisms, insertions, deletions, and other structural variants have been identified. The challenge is thus twofold: first, to identify which human genetic variations cause disease, and second, to elucidate how, at the molecular and cellular level, the genetic changes cause the diseases. The goal of this project is to generate human disease-associated genetic variations in the orthologous genes of C. elegans.

Modeling of human disease in C. elegans

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The actomyosin network is essential for cellular functions such as migration and adhesion, where force generation and sensing are important properties. Parallel actomyosin stress fibers crosslinked by a-actinin can additionally be crosslinked by highly structured arrays of myosin, called myosin stacks, that form when myosin regions in neighboring stress fibers align with each other [Hu et al., 2017]. In a recent study we could additionally show that this specific order of the cytoskeleton plays a role in the capacity of cells to generate forces [Hu, Grobe et al., 2019].

Actomyosin cytoskeleton in fibroblasts

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Contractile tubes are a hallmark of many important animal organs, such as blood and lymphatic vessels, lung airways, mammary and salivary glands, and urinal and reproductive tracts. In larger tubular tissues, contractility is afforded by smooth muscle cells surrounding epithelial cells, and in smaller tubes the epithelial or endothelial cells themselves are contractile. Misregulation of contractility, and hence of tube diameter, is responsible for several human diseases, such as hypertension and asthma. Mechanical cues, sensed by cell adhesion sites and the cytoskeleton, play an important role in regulating cellular contractility. 

Regulation of actomyosin contractility

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Embryogenesis comprises of serial, and on occasion simultaneous, occurrence of highly coordinated and regulated processes that lead to the formation of an organism. These processes are fairly conserved in all animal embryos. During embryogenesis, morphogenetic changes take place to bring about the formation of tissues from an initial mass of cells. Morphogenesis relies on individual and collective cell changes in shape, neighbourhood or identity to drive the generation and folding of individual tissues and organs to allow their functionality.  Extensive research has focused on the mechanisms that orchestrate morphogenesis, yet much remains unexplored.

Cytoskeleton dynamics in embryogenesis

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Cell migration is a critical developmental and physiological phenomenon for embryogenesis, wound healing, tissue repair and remodeling. Cells travel long or short distances to reach their final destination e.g. during embryogenesis cells of different lineages migrate in time and space to form specific tissues or organs at a predetermined location. Likewise, an injured or infected tissue sends out an inflammatory signal which rapidly recruits immune cells for the repair of damaged tissue regaining the tissue integrity. Defects in cell migration have severe consequences like birth defects, vascular disorders, neurological diseases etc. 

3D cell migration