Plasmodesmata are plant-unique intercellular communication channels, which allow plant cells to share their cytoplasm and build a multicellular or supracellular organism. These fundamental structures are expected to play crucial roles in orchestrating physiological and developmental programs as well as in controlling systemic defense responses against pathogens. However, what molecular players mediate the signaling through this unique communication system and how this process is mechanistically controlled are not known. The focus of this project is on gaining new insight into how the regulation of plasmodesmal signaling is specifically linked to the onset or progression of programmed cell death induced during developmental progression or by defense responses. By employing novel molecular tools, this project will attempt to correlate the inhibition of plasmodesmal function with controlled cell deaths. The two pressing questions driving this project are: what is the role of plasmodesmal signaling in cell death during defense response? How does a signal sensed at or transduced to the plasmodesmata link to a cell death pathway? Successful outcomes of this research project would provide compelling insights into the role of intercellular communication in death and survival of plant cells. In addition, new discoveries resulting from this project will also contribute to gaining a fundamental insight into how different organisms have independently evolved to meet the same goal of survival as multicellular organisms. As plasmodesmal function is essential for both cell-to-cell communication and long-distance signaling in plants, insights gained by this study could lead to the development of new agricultural technology. For example, manipulation of plants for resistance to the spread of pathogens could be achieved. This research project will actively engage undergraduate and graduate students in cutting-edge research and scientific communications as well as K-12 students in firsthand cell biology experience.