Phosphorylation of HDAC4 by CaMKII promotes nuclear export and derepression of HDAC target genes, which, in cardiomyocytes, will lead to hypertrophic growth (Backs et al., 2006), indicating a central role for CaMKII-HDAC4 signaling pathways in the development of cardiac hypertrophy. The gene discussed is HDAC9; the disease is cardiac hypertrophy.