[BK21 Plus Seminar]
           
             
          ▶Subject: Notum in vertebrate neural and head induction: insights on the “default” neural fate
                     
          ▶Speaker: Seong -Moon Cheong PH.D.
                         (Boston Children’s Hospital, Department of Neurology, Harvard Medical School)
                                  
          ▶Date: 4:00PM/July/13(Mon)/2015
                  
          ▶Place: Life Science Bldg. #104

                     
                 *Abctract
             Secreted Wnt morphogens are essential for embryogenesis and homeostasis, and require an unusual lipid/palmitoleoylate modification for receptor binding and activity. Notum is a secreted Wnt antagonist that belongs to the α/β hydrolase superfamily, but its mechanism of action and roles in vertebrate embryogenesis are not fully understood. We previously identified Tiki as a Wnt inactivating protease that cleaves the Wnt amino terminus and acts in the dorsal Organizer for Xenopus head formation. Here we report that Notum is an extracellular Wnt deacylase that hydrolyzes the palmitoleoylate adduct, resulting in inactivated Wnt proteins that form oxidized oligomers incapable of receptor binding. Notum is expressed in na?ve ectoderm and is required for Xenopus neural and head induction, indicating that distinct mechanisms of Wnt inactivation by Tiki in the Organizer and Notum in presumptive neuroectoderm cooperate in vertebrate brain development.

          ▶Inquiry: Prof. Han, Jin Kwan (279-2126)
                  
          * This seminar will be given in Korean.
  please refrain from taking photos during seminars. *