Ithai RabinowitchView all speakers
Ithai Rabinowitch studied Industrial Engineering at Tel Aviv University, then switched to neuroscience, carrying out a PhD at the Interdisciplinary Center for Neural Computation at the Hebrew University of Jerusalem, under the supervision of Prof. Idan Segev. His work consisted of computational modeling of the effects of homeostatic synaptic plasticity, a relatively slow and compensatory form of plasticity, in dendritic branches, the intricate tree-like structure stemming from neocortical neurons.
Ithai next embarked on a postdoc in Bill Schafer’s lab at the MRC Laboratory for Molecular Biology, Cambridge, UK, where he worked on natural and artificial modifications of neuronal connectivity in the nematode C. elegans and on combining mathematical modeling with neuroimaging to investigate the C. elegans nose touch circuit. Ithai is currently a postdoc in Millet Treinin’s lab at the Hebrew University of Jerusalem, continuing his work on artificial neural circuit connections and on cross-modal plasticity in C. elegans.
The beautiful field of synthetic biology is successfully modifying, converting or plainly reinventing cellular and molecular processes, with the aim of improving our understanding of biology, and perhaps even improving biology. We wished to adopt the perspective and principles of synthetic biology to neuroscience, targeting neuronal connectivity rather than genetic interactions, and reprogramming whole animal behavior rather than cellular function. The fundamental building blocks of neural circuits underlying neuronal connectivity are synapses. In order to artificially modify synaptic connectivity we sought to introduce a new synapse between adjacent neurons in an existing neural circuit. However, inserting heterologous chemical synapses into a circuit would be difficult due to their enormous complexity and hundreds of constituent proteins. In contrast, electrical synapses, or gap junctions, consist of as little as one protein type. Moreover, the molecular constituents of vertebrate and invertebrate gap junctions belong to completely distinct protein families: connexins are exclusive to vertebrates and innexins to invertebrates. Importantly, while proteins from the same family can interact to form heterotypic gap junctions, no compatibility has been found between connexins and innexins. Thus, we reasoned that connexins expressed heterologously in neurons of the invertebrate nematode C. elegans would form gap junctions exclusively between themselves, and that these new connections could be used to modify existing connections in intact animals. We demonstrate that a genetically modified mammalian connexin gene can be functionally expressed in the C. elegans nervous system. Using this approach, we have been able to target the insertion of functional electrical synapses into existing inhibitory and excitatory chemical synaptic connections in the C. elegans olfactory circuit. We present data demonstrating their impact on neural transmission as well as whole animal behavior.