Functional characterization of a calcium-permeable cation channel in plants

• Applicant: Professor Dr. Edgar Peiter
• Subject Area: Plant Biochemistry and Biophysics
• Term: from 2011 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 212350280

To counter abiotic and biotic stress, intricate signalling networks that govern the initation of defense and resistance responses have evolved in plants. The understanding of the central elements of stimulus-response coupling is vital for a targeted improvement of crops. A very early response of plants to most abiotic and biotic stress factors is an elevation of cytosolic free calcium ([Ca2+]cyt), which is mediated by the activation of Ca2+-permeable ion channels. Our knowledge on the molecular identity of those channel proteins is still very rudimentary, which presents a major obstacle in our understanding of signalling und stress responses in plants. The Ca2+-permeable Two Pore Channel 1 has previously been identified in the vacuolar membrane and initial analyses suggested its involvement in Ca2+-dependent processes. This project aims to elucidate the role of this channel in stimulus responses and to analyse the circumstances under which this channel is required in the generation of [Ca2+]cyt signals. Furthermore, the mode of negative feedback regulation of the channel and its activation by second messenger molecules will be analysed by a combination of electrophysiological and cell biological approaches, including [Ca2+]cyt imaging using aequorin and Yellow Cameleon techniques. The knowledge gained from those experiments will aid in our understanding of Ca2+ homeostasis and signalling, which may eventually be used in the design of crops with more efficient stress responses.

• DFG Programme: Research Grants