Cell size control in Chlamydomonas reinhardtii
Cell size homeostasis is the fundamental property to all organisms. The biggest challenge of studying cell-size control is that size checkpoint defects are difficult to assess due to concurrent growth and division processes. We use Chlamydomonas reinhardtii, a green alga, as a model system to dissect the genetic network governing size control mechanism because it offers a powerful haploid genetic system and utilizes a unique mitotic cell cycle that allows uncoupling of growth and division.
Our previous work has found that the retinoblastoma (RB) tumor suppressor pathway plays a pivotal role in regulating the size-mediated cell cycle control in Chlamydomonas. A particularly exciting discovery is that we have uncovered novel components functioning downstream of the RB pathway. Among them, a novel sulfate/anion transporter provides new insight into the connection between glutathione and cell cycle control. Our studies also reveals that a SUMO protease participates in RB-mediated cell cycle control. We are using transcriptomic and proteomic strategies to understand how these novel components are integrated into the size-mediated cell cycle control.
Growth and development in Phalaenopsis orchids
Phalaenopsis orchids are the economically important because they are the leading exporting ornamental plants in Taiwan. Improving growth and increasing the existing cultivars by marker-assisted molecular breeding are important to ensure the competitiveness of the orchids biotechnology in Taiwan. The research focus of orchid project in my lab is to improve efficiency of micropropagation. Our studies have revealed that protocorm-like body (PLB), direct shoot regeneration, and somatic embryogenesis have distinct developmental pathways that can be used for micropropagation. We use genome-wide comparative transcriptomic approach to decipher the molecular mechanisms underlying these different regeneration pathways. The final goal is to establish an efficient tissue culture platform for micropropagation of orchids.