[BK21 Plus Seminar] ▶Subject: Cross-talks between the control of flowering time and the response to salinity stress in plant ▶Speaker: Dae-Jin Yun, PH.D.(Department of Biochemistry, Gyeongsang National University) ▶Date: 4:00 PM/Jan. 26(Tue.)/2016 ▶Place: Auditorium(1F), Postech Biotech Center *Abctract The Salt Overly Sensitive (SOS) signaling pathway in Arabidopsis comprises the sodium transport protein SOS1, the protein kinase SOS2, and the calcium-binding protein SOS3. The SOS pathway maintains cellular sodium ion homeostasis, thereby imparting salt tolerance to all plant species that have been genetically tested. Environmental challenges, including salinity, typically entail retardation of vegetative growth and delay or cessation of flowering. The flowering time regulator GIGANTEA (GI) is a key component in the photoperiodic control pathway of flowering. Recently, our group discovered a molecular link between GI and adaptation to salt stress that is mechanistically based on GI degradation under saline conditions, thereby retarding flowering. GI and the salt tolerance-related protein kinase SOS2 interact physically. In the absence of stress, the GI:SOS2 complex prevents SOS2-based activation of SOS1, the major plant Na/H antiporter mediating adaptation to salinity. GI-overexpressing, rapidly flowering plants show greater salt sensitivity, whereas gi mutants exhibit delayed flowering and enhanced salt tolerance, in correspondence with the physical status of SOS2. Salt-induced degradation of GI confers salt tolerance by the release of the SOS2 kinase. The GI?SOS2 interaction introduces a higher order regulatory circuit that can explain in molecular terms, the long observed connection between floral transition and adaptive environmental stress tolerance in plant. ▶Inquiry: Prof. Hwang, Il-Doo (279-2291) * This seminar will be given in English. please refrain from taking photos during seminars. *