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 The research of this group focuses on the identification and characterization of new ion channels as well as the investigation of ion channel regulation mechanisms in ABA and environmental stress signaling transduction in Arabidopsis guard cells.
Principal Investigator: Dr. Yong-Fei Wang, Professor. Email: wangyongfei@sibs.ac.cn
Staff: Lu-Wen Yang, Research Assistant
Postdoctoral Fellow: Dr. Jia-Min Chen
Graduate Students: Ting Ban, Qi-Fei Gao
Identification and Characterization of New Ion Channels and a Study of Ion Channel Regulation Mechanisms in Arabidopsis Guard Cells
The stomata pore formed by two guard cells in the surface of plant leaves allows CO2 intake for photosynthesis and accounts for water loss, and ABA and environmental draught stress trigger stomata closure, which results in water saving and plant survival. Ion flux mediated by ion channels in the plasma membrane of guard cells is the main driving force of water flow and stomatal closure. Ion channel analysis is therefore extremely important. Multiple ion channels in the plasma membrane of guard cells, including S-type anion channel, K+ and Ca2+ channels, involve in ABA and draught stress induced stomata closure. However, the identities of a few channels as well as the regulation mechanism of all ion channels are largely unknown. My previous research discovered the gene of S-type anion channel (SLAC1), which is a key component of ABA signaling pathway. We also found multiple essential regulators of S-type anion channels and Ca2+ channels, including an ABC transporter (AtMRP5), CPK3 and CPK6. In collaboration with Dr. Julian Schroeder in UCSD, we recently cloned two putative calcium channel (Calcium-channel, CAC) genes, CAC1 and CAC2, as well as one upstream regulator gene of CAC1/CAC2, CACR (CAC-regulator). We found that CAC1 and CAC2 have multiple transmembrane domains and locate in the plasma membrane of N. benthamiana cells (Fig.2). The mutations of CAC1 and CAC2 impair the activation of guard cell inward Ca2+ channels and ABA-induced stomata closure in Arabidopsis (Fig.1). We are pursuing further experiments to uncover the functions of CAC1, CAC2 and CACR1 in ABA signaling and stomata closure. We are also working on other ion channels in parallel. Our research goal is to elucidate the regulation mechanisms of multiple ion channels in ABA and draught stress signaling, and may contribute to crop engineering.
Major Publications:
Vahisalu T, Kollist H, Wang YF (co-first author), et al. (2008) SLAC1 is required for plant guard cell S-type anion channel function in stomatal signalling. Nature 452: 487-491.
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