In these conditions there was a decrease in the expression of sarcoplasmic reticulum Ca2+ ATPase activity (Serca2a), a Ca2+ reuptake pump critical for cardiac contractility and whose reduced expression is a marker for heart failure, as well as of several genes encoding for proteins in the vicinity of the cardiac Z disk/titin cytoskeleton: Calsarcin-1, Casq2, Ldb3, Melusin and Titin. Furthermore, in miR-22-/- mice the transcription factor Purb is upregulated; this in turn negatively regulates Srf, itself a transcription factor that modulates Serca2a expression. The gene discussed is TTN; the disease is heart failure.