Calcium transport and sensing in TRPC channels - New insights into a complex feedback regulation
Jasmin Baron1, Klaus Groschner1, Oleksandra Tiapko1
1Gottfried-Schatz-Research-Center Medical Physics and Biophysics, Medical University of Graz, Neue Stiftingtalstrasse 6/H03, 8010 Graz, Austria.
Abstract:
Canonical TRP (TRPC) channels are a still enigmatic family of signaling molecules with multimodal sensing features. These channels enable Ca2+ influx through the plasma membrane to control a diverse range of cellular functions. Based on both regulatory- and recently uncovered structural features, TRPC channels are considered to coordinate Ca2+ and other divalent cations not only within the permeation path but also at additional sensory sites. Analysis of TRPC structures by cryo-EM identified multiple regulatory ion binding pockets. With this review, we aim at an overview and a critical discussion of the current concepts of divalent sensing by TRPC channels.
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