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Diacylglycerol (DAG) kinases (Dgk), which phosphorylate DAG to generate phosphatidic acid, act as either positive or negative key regulators of cell signaling. We previously showed that Src mediates growth factors-induced activation of Dgk-α, whose activity is required for cell motility, proliferation and angiogenesis. Here, we demonstrate that both hepatocytes growth factor (HGF) stimulation and v-Src transformation induce tyrosine phosphorylation of Dgk-α on Y335, through a mechanism requiring its proline-rich C-terminal sequence. Moreover, we show that both proline-rich sequence and phosphorylation of Y335 of Dgk-α mediate:(i) its enzymatic activation,(ii) its ability to interact respectively with SH3 and SH2 domains of Src,(iii) its recruitment to the membrane. In addition, we show that phosphorylation of Dgk-α on Y335 is required for HGF-induced motility, while its constitutive recruitment at the membrane by …