Towards understanding morphogenesis and function of phloem

  • Hit 104
  • Writer 최고관리자
  • 2017-10-23


[2017 Fall Life Sciences & IBB  Seminar]

▶Subject: Towards understanding morphogenesis and function of phloem

▶Speaker: Prof. Ykä Helariutta (University of Cambridge)
▶Date: 4:30PM/Oct. 27 (Fri.)/2017
▶Place: Auditorium(1F), POSTECH Biotech Center
▶Abctract: My group is investigating the morphogenesis of phloem, a long distance transporting tissue specified to transport the various products derived from the photosynthesis. Based on identification of the gain-of-function mutations in one of the callose synthase isoforms (responsible for formation of callose, b1, 3-glucan polymer that plant uses to regulate symplastic trafficking through plasmodesmata nanochannels) we have recently developed a molecular tool, icals3m, with which we can regulate symplastic molecular trafficking in a time and space specific manner [1].
Using this tool we have identified a family of genes coding for transcription factors that are transcribed in the young sieve element position, and whose protein products move to the adjacent procambial cells to complete procambial/phloem patterning. We are also investigating phloem development (with a focus on sieve element differentiation) in high resolution as a paradigm for how a plant cell progresses from stem cell to a fully differentiated state [2]. In the Arabidopsis root there are some 25 cells from the relatively isodiametric stem cell (touching the quiescent centre of the root) to the elongated cell that loses its nucleus as the final stage of sieve element cell differentiation. Finally, phloem transport is based on the interaction of the sieve element/ companion cell unit with their neighbouring cellular domains (in the root culminating at unfolding of organic substances to the meristem). We are now analysing aspects of plant morphogenesis (and also function) that may involve symplastic communication to the sink tissues through phloem.