Bound Ca²⁺ moves faster and farther from single open channels than free Ca².

ABSTRACT: A concept of Ca²⁺ nanodomains established in the cytoplasm after opening single-calcium channels helps mechanistically understand the physiological mechanisms of Ca²⁺ signaling. It predicts standing gradients of cytoplasmic free Ca²⁺ around single channels in the plasma membrane. The fate of bound Ca²⁺ attracted much less attention. This study aimed to examine the profiles of Ca²⁺ bound to low-mobility buffers such as bulky Ca²⁺-binding proteins. The solution of non-linear PDEs for an immobile buffer predicts fast decay of free [Ca²⁺] from the channel lumen and the traveling wave for bound Ca²⁺. For low-mobility buffers like calmodulin, the calculated profiles of free and bound Ca²⁺ are simil

SUBMITTER: Mironov SL 

PROVIDER: S-EPMC10761531 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature