Lack of functional wolframin causes drop in plasmalemmal sodium-calcium exchanger type 1 expression at early stage in rat model of Wolfram syndrome.

In previously introduced rat model of Wolfram syndrome, we have shown that in cardiac myocytes lacking functional wolframin protein the calcium transients and contractile response are significantly changed. Therefore, in this model, we evaluated protein and mRNA expression levels of following proteins involved in cardiac myocytes calcium homeostasis: the ryanodine receptor type 2, calsequestrin type 2, the junctophilin type 2 and plasmalemmal sodium-calcium exchanger type 1 (NCX1). For NCX1 we detected a significant decrease in expression both on protein and mRNA level. Thus, beyond its impact on endoplasmic reticulum stress, calcium, and mitochondria, wolframin influences processes in the myocyte plasma membrane.