Polycystin-2 functions as a calcium leak channel under endoplasmic reticulum stress to protect against myocardial ischemia.

Polycystin-2 acts as a PERK-dependent calcium leak channel under ER stress to protect against myocardial infarction in mice.

• Why it matters: Understanding how ER stress influences calcium signaling is crucial because unresolved ER stress worsens diseases like myocardial infarction, but the specific calcium sources involved are unclear.
• What they did: The study examined cardiomyocytes and MI models, finding that ER-localized polycystin-2 is upregulated during MI and facilitates an ER calcium leak at MERCs, requiring PERK phosphorylation.
• The result: This reveals that polycystin-2 provides mitochondrial calcium under ER stress in a PERK-dependent manner, and its upregulation may serve as a cardioprotective mechanism during MI.