Searching for Mechanisms Underlying the Assembly of Calcium Entry Units: The Role of Temperature and pH.

ABSTRACT: Store-operated Ca²⁺ entry (SOCE) is a mechanism that allows muscle fibers to recover external Ca²⁺, which first enters the cytoplasm and then, via SERCA pump, also refills the depleted intracellular stores (i.e., the sarcoplasmic reticulum, SR). We recently discovered that SOCE is mediated by Calcium Entry Units (CEUs), intracellular junctions formed by: (i) SR stacks containing STIM1; and (ii) I-band extensions of the transverse tubule (TT) containing Orai1. The number and size of CEUs increase during prolonged muscle activity, though the mechanisms underlying exercise-dependent formation of new CEUs remain to be elucidated. Here, we first subjected isolated extensor digitorum longus (EDL) muscles from wild type mice to an ex vivo exercise protocol and verified that

SUBMITTER: Girolami B 

PROVIDER: S-EPMC10049691 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature