The TRPA family is comprised of only one mammalian member, the TRPA1 (formerly named ANKTM1). TRPA1 is expressed in peripheral sensory neurons, where it is suggested to contribute to the detection of painful stimuli.
Originally it was thought that TRPA channels sensed painfully cold temperatures, but a more conservative description is that TRPA1 is sensitive to membrane/cytoskeletal perturbations by cold and perhaps stretch. In addition, it is sensitive to pungent natural compounds present in cinnamon oil, mustard oil, and wintergreen oil.