Oxygen is needed for the production of sufficient cellular energy to sustain life. Low oxygen availability, or anoxia, therefore has devastating effects on the viability of many organisms, including plants. Reduction in oxygen levels can come from the plant's own consumption of the available oxygen in densely packed tissues, or from the vagaries of the surroundings such as soil compaction, seasonal flooding and even agricultural practices related to cultivation or irrigation. Surviving these conditions requires the plant to sense the lowering of oxygen availability and shift its energy metabolism to systems to cope with the impending energy deficit. Although this response is essential for survival, our current understanding of this sensory system in plants is highly incomplete, especially at the level of the cellular events that sense and signal a fall in oxygen availability. Therefore, the research in this proposal seeks to more fully characterize the early events that trigger, coordinate and regulate plant responses to low oxygen availability using an integrated approach of imaging of low oxygen-related cellular signaling activities, characterization of associated changes in gene expression and analysis of the responses of mutants impaired in these cell and molecular events. In addition to advancing fundamental knowledge of how plants adapt to the environment, the research in this proposal will also be of long-term relevance to agriculture where seasonal flooding, likely exacerbated by climate change, may become a significant factor in future crop productivity. Integrated into this basic research is also an effort to develop a plant biology movie resource aimed at engaging and educating the general public. This effort will intimately involve undergraduate students in the making and presentation of the movies.