An anhydrobiotic cell line expressing odorant receptors shows odorant responses after dry storage

Odorant receptor-expressing cells have been shown to recognize various odors, which has brought them to the interest of the growing field of cell-based olfactory sensors. However, cell cultures are difficult to use outside a laboratory because of their continuous need for controlled conditions. In this study, the odorant receptor DmOr47a, the co-receptor DmOrco, and the calcium-sensing fluorescent protein GCaMP6f were stably expressed in a Pv11 cell line (Pv11-00443-Or47a), which is desiccatable. This cell line not only retained desiccation tolerance, but also showed dose-dependent fluorescence responses to the DmOr47a ligand pentyl acetate that were recovered 12 h after rehydration. Even more importantly, Pv11-00443-Or47a showed a response to the agonist of DmOrco just 1 h after rehydration, even upon inhibition of protein synthesis. This result demonstrates for the first time that a transmembrane protein can be dry-stored in an orthologous cell culture system. This work also constitutes an initial step towards the development of improved desiccatable sensing cells for use in portable devices.