9808729 Wang Transduction of biotic and abiotic cues to the cell often requires the function of phospholipases. Activation of Phospholipase D (PLD) generates second messengers and is involved in a broad range of cellular processes, including cell growth, proliferation, differentiation, reproduction, and defense responses. The goals of this project are to understand the mechanisms by which PLDs exert their cellular effects and to identify cellular targets of PLD activation. To elucidate the cellular activation of PLDs, this study will address if PLDs are regulated by phosphorylation and how different PLDs interact with and are stimulated by polyphosphoinositides. To identify the downstream targets of PLD activation, this project will determine if protein physphorylation and reactive oxygen generation are altered in PLD-deficient transgenic Arabidopsis and if PLD activation affects other lipid signaling processes. In addition, the role of PLD in the phytohormone, abscisic acid, response will be investigated. Completion of this project will fill critical gaps in the current knowledge of PLDs and lipid-based signaling in plant growth and development. This study may also identify novel ways to enhance seed germination and to decrease plant post-harvest and in-field losses.
