The death and survival of a cell are precisely controlled during an organism's development and in its response to environments. Many human diseases are caused by a failure in regulating normal cell death processes. Programmed cell death (PCD) is also associated with a variety of developmental processes in plants. However, the plant-encoded molecular machinery that regulates and executes PCD remains largely unknown. The proposed study employs a combination of molecular, genetic, and cell biology approaches to dissect the PCD process mediated by the aspartic protease PCS1, a protein-processing enzyme, using the model plant Arabidopsis. PCS1 has been found to function as an anti-cell death component. Loss of PCS1 function causes excessive cell death of developing gametophytes and embryonic tissues, whereas its over-expression leads to blockage of some normal cell death processes. Cell biology tools will be used to characterize the PCS1-mediated cell death process. Genetic and molecular approaches will be used to identify other components involved in the PCD pathway. The study will advance our understanding of molecular mechanisms that regulate cell death and survival in developmental processes in plants. This project will also make available a useful tool for engineering agriculturally important traits of crops and provide an excellent cross-disciplinary training opportunity for students and post-doctoral fellows.
