[2019 Spring Life Sciences & IBB Seminar]
▶Subject: Plant thermomorphogenesis -Warm temperature sensing, signaling, and adaptation-
▶Speaker: Prof. Chung-Mo Park (Department of Chemistry, Seoul National University)
▶Date: 4:15PM/Apr. 12(Fri.)/2019
▶Place: Auditorium(1F), Postech Biotech Center
Plant growth and development is profoundly affected by diverse temperature conditions. While studies have been focused mainly on the effects of stressful temperature extremes in recent decades, accumulating evidence strongly support that nonstressful ambient temperatures also influence a wide array of plant morphogenic aspects, a process termed thermomorphogenesis.
At high ambient temperatures, developing seedlings exhibit a series of architectural changes, such as accelerated hypocotyl elongation, increased leaf hyponasty, and reduction of stomatal density. One such example is the effects of warm temperatures on the heterotrophic-to-autotrophic transition in plants. Chlorophyll biosynthesis enables autotrophic development of developing seedlings. Upon light exposure, the chlorophyll precursor protochlorophyllide produces reactive oxygen species (ROS). Developing seedlings acquire photosynthetic competence through the action of protochlorophyllide oxidoreductases (PORs) that convert protochlorophyllide to chlorophyllide, reducing ROS production that would otherwise induce cellular damages and chlorophyll bleaching. Here, we show that FCA mediates the thermostabilization of PORs to trigger the conversion of protochlorophyllide to chlorophyllide in developing seedlings. FCA also facilitates the thermal induction of POR genes through histone acetylation that promotes the accessibility of RNA polymerases to the gene promoters. The combined action of FCA maintains PORs at warm temperatures, shifting chlorophyll-ROS balance towards autotrophic development. We propose that the FCA-mediated thermal adaptation of autotrophic development allows developing seedlings to cope with the heat-absorbing soil surface layer under natural conditions. The thermal adaptive mechanism would provide a potential basis for studying crop performance at warm temperatures.
▶Inquiry: Prof. Youngsook Lee (279-2296)
* This seminar will be given in English.
Please refrain from taking photos during seminars. *