A Membrane Potential- and Calpain-Dependent Reversal of Caspase-1 Inhibition Regulates Canonical NLRP3 Inflammasome.

ABSTRACT: The NLRP3 inflammasome senses a range of cellular disturbances, although no consensus exists regarding a common mechanism. Canonical NLRP3 activation is blocked by high extracellular K⁺, regardless of the activating signal. We report here that canonical NLRP3 activation leads to Ca²⁺ flux and increased calpain activity. Activated calpain releases a pool of Caspase-1 sequestered by the cytoskeleton to regulate NLRP3 activation. Using electrophysiological recording, we found that resting-state eukaryotic membrane potential (MP) is required for this calpain activity, and depolarization by high extracellular K⁺ or artificial hyperpolarization results in the inhibition of calpain. Therefore, the MP/Ca²⁺/calpain/Caspase-1 axis acts as an independent re

SUBMITTER: Zhang Y 

PROVIDER: S-EPMC6201321 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature