NSF/MCB-BSF: Development of novel CRAC channel photoswitches

This project will provide new molecular tools and understanding about Calcium Release Activated Calcium (CRAC) channels. These are key proteins that affect calcium entry and signaling in cells. Calcium is one of the most important signaling molecules in living cells.

Understanding calcium entry and signaling has important implications in understanding numerous cellular processes including migration, proliferation, and gene expression. This NSF-BSF project is led by researchers at the University of Maine in the US, in collaboration with researchers at the Technion in Haifa, Israel. As part of this international collaboration, graduate and undergraduate students will be trained in interdisciplinary research at the interface of organic chemistry, molecular biology, and biophysics.

Interactions and training will be facilitated through regular video meetings and travel to the collaborator’s laboratory in Israel. As a complimentary goal, the Broader Impacts of this proposal will increase research participation of traditionally underrepresented groups in STEM at the University of Maine, particularly women and first-generation college students.

The overarching goal of this project is to better understand and control the function of CRAC channels, which are an essential component of store-operated calcium entry (SOCE), an evolutionary conserved mechanism that regulates intracellular calcium levels in metazoans. The first aim of this proposal will combine synthetic chemistry and molecular biology in order to develop small molecule Light Operated CRAC Channel Inhibitors (LOCIs), which will provide rapid and reversible control of the function of both native and genetically engineered CRAC channels.

A set of LOCIs with different photophysical properties will be synthesized and evaluated using electrophysiological and live cell imaging techniques. As there are multiple CRAC channel isoforms, the second Aim of this project will combine synthetic chemistry and genetic engineering to develop new types of LOCIs with two-component optogenetic constructs that will enable covalent tethering of LOCIs to the cell membrane or directly to different CRAC channel components.

These constructs will enable the control of CRAC channel activity in a cell-type and isoform specific manner and with high spatial and temporal precision. Finally, LOCIs will be used as light activated modulators of calcium dependent biological processes, particularly cell migration and gene expression.

This collaborative US/Israel project is supported by the US National Science Foundation and the Israeli Binational Science Foundation.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.