- Chronic phospholamban-sarcoplasmic reticulum calcium ATPase interaction is the critical calcium cycling defect in dilated cardiomyopathy. Minamisawa, S., Hoshijima, M., Chu, G., Ward, C.A., Frank, K., Gu, Y., Martone, M.E., Wang, Y., Ross, J., Kranias, E.G., Giles, W.R., Chien, K.R. Cell (1999)