Molecular and genetic screening for new components of the CHLORAD system in plants

Plastid organelles are found within all plant species and are responsible for a wide range of fundamental processes including photosynthesis, stress responses and resource management. Chloroplasts are the most well-known and studied member of the plastid organelle family and are chiefly responsible for facilitating the photosynthetic process. Fully functional chloroplasts are composed of a total of ~2000-3000 proteins, of which only ~100 are encoded for within the chloroplast itself. The majority of a chloroplast's proteins are encoded for within nuclear DNA and are synthesised as tagged protein precursors in the cytosol. These precursor proteins undergo a translocation process in which they are imported into the chloroplast organelle, through the paired TOC (translocon on the outer chloroplast membrane) and TIC (translocon on the inner chloroplast membrane) machinery. Through ubiquitin-mediated degradation of TOC proteins, levels of protein import are tightly regulated. Understanding the fundamental processes that govern how protein import into plastids is controlled provides great insight into important processes such as maintenance of photosynthetic machinery, abiotic stress responses, and plant aging/ripening. This project aims to explore potentially undiscovered interactors of the protein import apparatus, as well as components of the CHLORAD system that regulates them, through a variety of molecular and genetic screens in order to further the current understanding of the mechanisms and implications of protein import within plants.