Abstract: TOR(target of rapamycin)，a protein kinase with high conservation in structure and function from yeast to mammalian， controls the cell growth and cycle progress by integrating the nutrient， energy and growth factors. The authors reviewed TOR kinase and the related upstream and downstream signaling pathways， and the regulation of amino acid and energy on these signals and subsequently cell growth， for establishing the mechanism of nutrient regulating protein position and providing a new insight into the technology of exact nutrient provision.

Key words: amino acids; energy; TOR; signal transduction; cell growth