Date: 14th May 2025
Time: 13:00
Title: Investigating leaf epidermis: from development to tissue organization and unique features
Location: Auditorium 1041, Biocentre 2, Viikinkaari 5
Host: Anne Vaten
Abstract: The leaf epidermis plays a crucial role as the plant's frontline, regulating CO2 entry for photosynthesis while providing protection against dehydration. This talk will explore the importance and uniqueness of the leaf epidermis from three perspectives: cell, tissue, and morphology. First, the leaf epidermis comprises multiple cell types organized in specific patterns. However, how the epidermal stem cells decide to differentiate into different cell types has been a critical question in developmental biology. Unlike the previous understanding of homeodomain proteins as transcription factors, we identified a novel homeodomain-like (HDL) protein that interacts with histone modifiers to form chromatin condensates during the S phase, reshaping the chromatin landscape and influencing cell cycle and fate decisions. Second, I will examine how epidermal cells affect the arrangement of the underlying mesophyll cells and demonstrate the significance of coordinated tissue growth for efficient photosynthesis. Lastly, I will use luffa as an example to illustrate how our research can be applied in agriculture. The leaf structure of luffa contains extrafloral nectaries that play a role in plant defense. We found that these extrafloral nectaries are actually specialized features of the leaf epidermis, and the cellular arrangement within the leaf tissue facilitates nectar secretion. By elucidating leaf epidermal development and its role in leaf tissue organization, we can better understand developmental plasticity in plants and explore opportunities for enhancing plant growth under changing conditions.
Kimmy Ho is an associate research fellow at the Institute of Plant and Microbial Biology, Academia Sinica, Taiwan. She has been interested in how cells divide appropriately and obtain specific cell fates in a complex tissue. As a principal investigator in Academia Sinica, her group investigates the leaf epidermal development, focusing on the cell fate determination, cuticle formation and the arrangement of mesophyll cells integrated to form proper epidermal patterns and achieve better water use efficiency. In 2024, she was selected as a member of the EMBO global investigators.