9416038 Harper This research is focused on exploring the role of Calcium-Dependent Protein Kinases (CDPKs) in mechano-sensory signal transduction. The three specific aims are to: 1) Identify substrates for CDPK- dependent signal transduction pathway, 2) Test the hypothesis that the activity of CDPK isoform AK1 is critical to a mechano-sensory response, and 3) Develop a fluorescent tagging system to monitor dynamic changes in the membrane/cytoskeletal systems of live cells in response to physical stimulation. Since many mechano-sensory responses appear to involve calcium signals, it is important to determine what role CDPKs are playing in these phenomena. Using a CDPK signal transduction pathway as a focus, this research emphasizes the development of unique collaborations and new tools with far reaching implications for research in the field of plant cell biology. For example, the specific aim to identify CDPK substrates will involve a collaboration of researchers from all areas of plant biology. In the second specific aim, the transgenic plants expressing a mutant CDPK will be made available as a tool to all researchers seeking to define the signal transduction pathways involved in a plant's response to an environmental signal. Finally, it is hoped that the tool developed in the third specific aim, GFP tagged membrane/cytoskeletal systems, will provide a foundation for a powerful new approach in investigating the dynamics of cell structure. ***
