FIG. 2.

PM activation of TRPV1, M8, and A1. (A) Activation of TRPA1 via mechanical stimuli is proposed to be similar to that of TRPV1 and M8. TRPA1 is also activated by organic extracts of combustion-derived PM through the electrophilic and menthol/propofol binding sites. (B) TRPV1 activation by coal fly ash is proposed to occur through charge and mechanical interactions with the poor-loop region, as described in our most recent publication (Deering-Rice et al., 2012), resulting in cell-type specific responses (epithelial vs. neuronal). (C) Due to sequence similarity between TRPM8 and V1, mechanical activation by PM is proposed to occur in the poor-loop region. (A color image is available in the online version.)