Disordered Motifs and Domains in Cell Control
Monday Speaker Abstracts
Plant Stress: Membrane Binding of the Disordered Plant Dehydrins
Pia Harryson
.
Stockholm University, Stockholm, Sweden.
Sudden temperature changes and vanishing supply of water present major challenges to plant
survival, growth and productivity. This project investigates the biological and molecular function
of the stressed induced dehydrin proteins to broaden our understanding on how plants adapt to
drought, temperature changes or salty soils. Although highly expressed during stress is the
molecular function of dehydrins yet unclear. Dehydrins are intrinsically disordered proteins
expressed under water-related stress in plants. As a clue to their function, some dehydrins are
found to interact in an orderly manner with negatively-charged lipids, supporting the idea of a
key role in safeguarding membrane integrity. We have earlier reported that this lipid interaction
is modulated electrostatically by global and local charge. Of particular interest is the pronounced
effect of local charge that shed light on how dehydrin function is regulated in vivo: membrane
binding and vesicle assembly is controlled by protonation of histidine switches flanking the
conserved K-segments. However, the lipid binding capacity varies among the 4 dehydrins in this
study, from some showing low/no binding examples of strong specific binding. These data
indicate a functional diversity among the plant dehdyrins.
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