Differential adhesion between cadherin subtypes expressed on cell surfaces is postulated to direct cell segregation during tissue morphogenesis. The studies described here used magnetic twisting cytometry and traction force microscopy to test the impact of cadherin binding selectivity on mechanotransduction and substrate rigidity sensing at cadherin-based adhesions. Micropipette measurements in turn quantified the binding affinities of different cadherin subtypes. Here we present evidence that the ability to transduce mechanical information across cadherin junctions depends on the identity of the ligand, such that only homophilic bonds between identical cadherins support force-activated junction remodeling. Mechanical stimulation with dissimilar cadherins or with anti-cadherin antibodies failed to elicit any response to force. Surprisingly, this behavior does not correlate with protein binding affinities, suggesting that mechanical differences may supercede protein-binding affinities in controlling intercellular organization during development.
Hamid Tabdili was born in Iran and grew up in Tehran, the capital city. He received his B.Sc. degree from Sharif University of Technology in Material Science and Engineering. Later on he moved to England to continue his education in Biomedical Engineering with the focus on Biomedical Applications of Polymers at the University of Sheffield. He graduated with his M.Sc. under the supervision of Professor Short. The title of his thesis was "Nanofabrication of DNA microarray using plasma polymerization". He then came to the U.S. for his Ph.D. studies in 2007, and he was fortunate to be accepted in Professor's Deborah Leckband's Lab at the University of Illinois at Urbana-Champaign. Currently as a Ph.D. candidate he is working on his thesis which is on mechanotransduction at intercellular junction. The main focus of his research is on studying the parameters that modulate cadherin mechanosensing mechanism. The main goals of the project are identifying the key cytoskeletal components and molecular pathways in cadherin-mediated mechanosensing, as well as investigating the potential signaling molecules that are force-dependent and/or modulate the force dependent response through cadherin. Hamid is interested in a research career in leading biotech companies. Outside his education, he is a huge fan of sports, mostly tennis and ski. He is also interested in learning new languages, and is currently studying Spanish as his third language. He is also a huge fan of poetry and Classical music.
From Hamid Tabdili's Trainee profile
Midwest Cancer Nanotechnology Traning Center (M-CNTC) Training the next generation of leaders who will define the new frontiers and applications of nanotechnology in cancer research It is known that more than 1.5 million Americans were diagnosed with cancer during 2010, and half a million have died (Cancer Statistics 2010, ACS). In spite of considerable effort, there has been limited success in reducing per capita deaths from cancer since 1950. This calls for a paradigm shift in the understanding, detection, and intervention of the evolution of cancer from a single cell to tumor scale.
In response to this challenge the M-CNTC has assembled a preeminent interdisciplinary team of researchers and educators across the University of Illinois and clinical collaborators in the Midwest to train the next generation of engineers, physical scientists, and biologists to address the challenge of understanding, managing, diagnosing, and treating cancer using the most recent advancements in nanotechnology.
Cellular and Molecular Mechanics and Bionanotechnology (CMMB-IGERT) Training the next generation of leaders who will define the new frontiers of cellular and molecular mechanics and bionanotechnology Critical experiments during the last decade show a fundamental link between the micro- and macro-mechanical environment (i.e., intracellular forces, local shear, gravitational force) and a variety of cell functionalities, their lineage, and phenotype. These findings pose the grand challenge: what is the underlying molecular mechanism that cells employ to transduce mechanical signals to biochemical pathways?
In response to this challenge the CMMB IGERT launched an interdisciplinary research effort with national and international collaborators.