TRPC Channels in the SOCE Scenario

• Main Authors: Jose J. Lopez, Isaac Jardin, Jose Sanchez-Collado, Ginés M. Salido, Tarik Smani, Juan A. Rosado
• Format: Article
• Language: English
• Published: MDPI AG 2020-01-01
• Series: Cells
• Subjects: trpc1; stim1; orai1; calcium influx; store-operated ca²⁺ entry (soce)
• Online Access: https://www.mdpi.com/2073-4409/9/1/126

Transient receptor potential (TRP) proteins form non-selective Ca²⁺ permeable channels that contribute to the modulation of a number of physiological functions in a variety of cell types. Since the identification of TRP proteins in <i>Drosophila</i>, it is well known that these channels are activated by stimuli that induce PIP₂ hydrolysis. The canonical TRP (TRPC) channels have long been suggested to be constituents of the store-operated Ca²⁺ (SOC) channels; however, none of the TRPC channels generate Ca²⁺ currents that resemble <i>I</i>_CRAC. STIM1 and Orai1 have been identified as the components of the Ca²⁺ release-activated Ca²⁺ (CRAC) channels and there is a body of evidence supporting that STIM1 is able to gate Orai1 and TRPC1 in order to mediate non-selective cation currents named <i>I</i>_SOC. STIM1 has been found to interact to and activate Orai1 and TRPC1 by different mechanisms and the involvement of TRPC1 in store-operated Ca²⁺ entry requires both STIM1 and Orai1. In addition to the participation of TRPC1 in the <i>I</i>_SOC currents, TRPC1 and other TRPC proteins might play a relevant role modulating Orai1 channel function. This review summarizes the functional role of TRPC channels in the STIM1&#8722;Orai1 scenario.