[초청강연] Lipid-mediated regulation of flowering in plants

연제: Regulation of flowering time by membrane phospholipid PG
abstract:
Plants respond to temperature changes by modulating florigen activity to
optimize the timing of flowering. We show that the Arabidopsis thaliana mobile
florigen FLOWERING LOCUS T (FT) interacts with the negatively charged
phospholipid phosphatidylglycerol (PG) at cellular membranes and binds the
lipid bilayer. Perturbing PG biosynthesis in phloem companion cells leads to
temperature-insensitive early flowering. Low temperatures facilitate FT
sequestration in the cellular membrane of the companion cell, thus reducing
soluble FT levels and delaying flowering. A mutant
in PHOSPHATIDYLGLYCEROLPHOSPHATE SYNTHASE 1 accumulates more
soluble FT at lower temperatures and exhibits reduced temperature sensitivity.
Thus, cellular membranes sequester FT through their ability to bind the
phospholipid PG, and this sequestration modulates the plant’s response to
temperature changes.