1. Bandell, M., Story, G.M., Hwang, S.W., Viswanath, V., Eid, S.R., Petrus, M.J., Earley, T.J., and Patapoutian, A. (2004). Noxious cold ion channel TRPA1 is activated by pungent compounds and bradykinin. Neuron 41, 849–857.2. Jordt, S.E., Bautista, D.M., Chuang, H.H., McKemy, D.D., Zygmunt, P.M., Ho¨ gesta¨ tt, E.D., Meng, I.D., and Julius, D. (2004). Mustard oils and cannabinoids excite sensory nerve fibres through the TRP channel ANKTM1. Nature 427, 260–265.3. Bahia, P.K., Parks, T.A., Stanford, K.R., Mitchell, D.A., Varma, S., Stevens, S.M., Jr., and Taylor-Clark, T.E. (2016). The exceptionally high reactivity of Cys 621 is critical for electrophilic activation of the sensory nerve ion channel TRPA1. J. Gen. Physiol. 147, 451–465.4. Hinman, A., Chuang, H.H., Bautista, D.M., and Julius, D. (2006). TRP channel activation by reversible covalent modification. Proc. Natl. Acad. Sci. USA 103, 19564–19568.5. Macpherson, L.J., Dubin, A.E., Evans, M.J., Marr, F., Schultz, P.G., Cravatt, B.F., and Patapoutian, A. (2007). Noxious compounds activate TRPA1 ion channels through covalent modification of cysteines. Nature 445, 541–545.6. Bahia, P.K., Parks, T.A., Stanford, K.R., Mitchell, D.A., Varma, S., Stevens, S.M., Jr., and Taylor-Clark, T.E. (2016). The exceptionally high reactivity of Cys 621 is critical for electrophilic activation of the sensory nerve ion channel TRPA1. J. Gen. Physiol. 147, 451–465.7. Palovcak, E., Delemotte, L., Klein, M.L., and Carnevale, V. (2015). Comparative sequence analysis suggests a conserved gating mechanism for TRP channels. J. Gen. Physiol. 146, 37–50.8. Paulsen, C.E., Armache, J.P., Gao, Y., Cheng, Y., and Julius, D. (2015). Struc- ture of the TRPA1 ion channel suggests regulatory mechanisms. Nature 520, 511–517.