Research
We seek to understand the regulation of the algal CO2- concentrating mechanism.
As the most important biological process on Earth, photosynthesis fixes CO2 from the environment, forming the foundation for all kinds of carbon-based materials that impact nearly every aspect of our daily lives, including food, clothing, housing, fuel, and medicine.
Approximately 30-40% of global CO2 fixation is mediated by the algal CO2-concentrating mechanism (CCM). This CCM enhances photosynthetic CO2 fixation and is present in most eukaryotic algae. Evidence suggests that engineering CCMs into non-CCM crops could increase yields by up to 60%, while reducing water and nitrogen fertilizer usage.
The algal CCM is inducible, and algal cells only activate their CCM when necessary to conserve energy, responding rapidly to environmental changes. Defects in CCM activation can lead to cell death, underscoring the importance of precise regulation. Understanding the regulation of the algal CCM is crucial not only for uncovering the basic principles underlying global-scale algal CO2 fixation but also for optimizing engineered algal CCM to promote sustainable agriculture, enhance biofuel production, and advance carbon capture technologies.
Despite its global significance, fundamental questions about the regulation of the algal CCM remain unanswered. For example, although it is known that the induction of the algal CCM is triggered by light and limiting CO2 levels (air level or lower), how algae sense these changing signals and activate the CCM remains unknown. Moreover, the activation of the algal CCM is accompanied by the upregulation of numerous CCM genes, indicating large-scale transcriptional regulation, yet the underlying mechanism is unclear. Additionally, the rapid initiation of algal CCM induction and the detection of phosphorylation on key CCM proteins suggest a potentially major role for phosphorylation. However, no kinase that regulates CCM proteins has been identified. Answering these questions will provide a comprehensive understanding of how algal cells perceive external signals and regulate the CCM at both the transcriptional and post-translational levels. This knowledge will significantly advance our molecular understanding of algal CCM regulation and guide efforts to optimize its engineering for agricultural and environmental applications.
Our lab investigates the regulation of the algal CCM using cutting-edge approaches in genetics, molecular biology, cell biology, biochemistry, biophysics, and structural biology. Using the well-established model alga Chlamydomonas reinhardtii, we aim to elucidate how algal cells detect environmental changes and activate their CCM through coordinated gene expression and protein modification. Our findings will advance the understanding of the regulatory mechanism of algal CCM, and contribute to tackling major global challenges, including enhancing food security and supporting sustainable agricultural practices, which will ultimately improve the lives of millions of people worldwide.
