Impact of Ca²⁺ signaling on B cell function

In B cells, changes in intracellular concentration of Ca²⁺ drive signal transduction to initiate changes in gene expression and various cellular events, including apoptosis and differentiation. B cell receptor engagement causes a transient Ca²⁺ flux from the endoplasmic reticulum Ca²⁺ store, followed by a continuous increase in intracellular Ca²⁺ concentration, mainly resulting from store-operated Ca²⁺ entry (SOCE). The recent identification of stromal interaction molecule (STIM) and Orai as essential components for SOCE has allowed researchers to probe further the role of Ca²⁺ signals in B cell biology. Here, we summarize the B cell signaling pathways that lead to SOCE, the role of Ca²⁺ signals in B cell regulatory function, and how a breakdown in the balance of Ca²⁺ signals is associated with immune-related disease.