Emerging Concepts in Ion Channel Biophysics

Emerging Concepts in Ion Channel Biophysics

Thursday Speaker Abstracts

Temperature-dependent Gating in Ion Channels Feng Qin . State University of New York at Buffalo, Buffalo, NY, USA.

Mammals involve specific sensory neurons for pain and thermal sensation. Recent discoveries of transient receptor potential (TRP) channels have unraveled a group of thermal TRP channels that are responsible for transduction of physiologically relevant temperatures as well as detection of chemical cues especially those correlated to thermal perception (e.g. capsaicin, the hot ingredient of chili peppers, menthol, a cooling compound from mint, and oregano, savory and thyme, the warmth-producing spices). Thermal TRP channels are directly activated by temperature and exhibit unprecedented strong temperature dependence, some of which reach a Q10 value as large as 100, as compared to a value of 2-3 for most ion channels. The strong temperature dependence of thermal channels results from a large enthalpy change between closed and open states, about five times that of ligand- or voltage-gated channels. But how and where thermal TRP channels attain the large energetic has long been a mystery. We have investigated, by unique fast temperature jumps, the heat activation of vanilloid receptors (TRPV1-4) and have explored the biophysics and molecular basis underlying temperature sensing by the channels. This lecture will present our understanding of mechanisms of temperature-dependent gating in ion channels and will discuss critical issues and challenges facing the study of thermal channels.

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