1. Annexin A3: a newly identified player in store‑operated calcium entry.
- Author
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Dyrda A, Kuznicki J, and Majewski L
- Subjects
- Animals, Calcium Signaling, ORAI1 Protein, Stromal Interaction Molecule 1 genetics, Zebrafish metabolism, Annexin A3 metabolism, Calcium metabolism, Calcium Channels genetics, Calcium Channels metabolism
- Abstract
Store‑operated calcium entry (SOCE) is important for refilling endoplasmic reticulum (ER) Ca2+ stores and Ca2+ signaling. Extracellular Ca2+ is conducted by highly Ca2+‑selective Orai channels that are activated by stromal interaction molecule proteins (STIMs), which are sensitive ER Ca2+ sensors. We found an approximately five‑fold increase in annexin A3a (anxa3a) expression levels in stim2b knockout zebrafish. The present study investigated whether annexin A3 protein is involved in SOCE. We used Ca2+ imaging and electrophysiological recordings to determine the effect of annexin A2, A3, and A6 overexpression on SOCE and Orai-dependent Ca2+ currents (ICRAC) in cultured cells. Annexin A3 increased SOCE amplitude and potentiated Ca2+ ICRAC currents. These results suggest that annexin A3 is a positive modulator of SOCE.
- Published
- 2021