The mAKAP signalosome and cardiac myocyte hypertrophy

Cardiac hypertrophy is regulated by a large intracellular signal transduction network. Each of the many signaling pathways in this network contributes uniquely to the control of cell growth. In the last few years, it has become apparent that multimolecular signaling complexes or 'signalosomes' are important for mediating crosstalk between different signaling pathways. These complexes integrate upstream signals and control downstream effectors. In the cardiac myocyte, the protein mAKAPbeta serves as a scaffold for a large signalosome that is responsive to upstream cAMP, Ca(2+), and mitogen-activated protein kinase signaling. The mAKAPbeta signalosome is important for the control of NFATc transcription factor activity and for the overall induction of myocyte hypertrophy.