Recent advances in stem cell biology have established the feasibility of 
reprogramming human and murine fibroblast cells into induced pluripotent stem 
cells. Three master regulators have been demonstrated to be sufficient in the 
management of cell status of 'pluripotent' versus 'differentiated'. The same 
strategy has been used to directly convert one somatic cell type into another 
cell type, such as the converting of exocrine pancreas cells into cells closely 
resembling beta cells and the reprogramming of fibroblast cells into functional 
neuron cells. Srivastava's group reported the first direct reprogramming of 
mouse fibroblast cells into mesoderm lineage cells (cardiomyocytes) with the 
enforced expression of three cardiac transcriptional factors: Gata4, Mef2c, and 
Tbx5. The induced cardiomyocytes exhibit a global gene expression profile and 
basic electrophysiological characteristics similar to those of postnatal 
cardiomyocytes. This study made significant advances in cardiovascular and stem 
cell fields and has important implications in understanding heart developmental 
biology as well as in potential therapies of human cardiovascular diseases.