Plasma Membrane Lipids Associated with Genetic Variability in Freezing Tolerance and Cold Acclimation of Solanum Species

Abstract

Simultaneous comparisons were made between a freezing-tolerant, cold-acclimating (CA) wild potato species (Solanum commersonii) and a freezing-sensitive, nonacclimating (NA) cultivated species (Solanum tuberosum). Comparative studies allowed differentiation of plasma membrane lipid changes associated with increased freezing tolerance following CA from lipid changes that can result from metabolic adjustment to reduced temperature during CA. Following CA treatment lipid changes found in both the NA and CA species included a decrease in palmitic acid, an increase in unsaturated to saturated fatty acid ratio, an increase in free sterols, an increase in sitosterol, and a slight decrease in cerebrosides. Lipid changes detected only in the acclimating species included an increase in phosphatidylethanolamine, a decrease in sterol to phospholipid ratio, an increase in linoleic acid, a decrease in linolenic acid, and an increase in acylated steryl glycoside to steryl glycoside ratio. These changes were either absent or opposite in the NA species, suggesting an association of these lipid changes with CA. Furthermore, the lipid changes associated with increased freezing tolerance during CA were distinct from lipid differences between the two species in the NA state.

Differential Effect of Plant Lipids on Membrane Organization

“…3). These data demonstrate an impact of ASG/SG amount on membrane physical properties and suggest that the changes in the ratio of conjugated to free forms of sterol could be a major key to modulate the phase behavior of PM, as observed, for example, during dehydration (105). In agreement with such a model, compensatory changes in free sterol versus SG plus ASG suggest an interconversion of the lipids during cold acclimation in rye seedlings (106) or in A. thaliana (107).…”

The Role of Arabidopsis ABCG9 and ABCG31 ATP Binding Cassette Transporters in Pollen Fitness and the Deposition of Steryl Glycosides on the Pollen Coat

“…In plant cells, steryl glycosides are mainly found at the plasma membrane (Hartmann and Benveniste, 1987), where they might regulate membrane properties (Ullmann et al, 1987;Palta et al, 1993;Warnecke et al, 1999). However, no direct evidence for the function or localization of steryl glycosides has been provided for pollen, either at the plasma membrane or in the coat.…”

Drought and extreme temperature tolerance for <em>Tillandsia dasyliriifolia</em>, an epiphytic bromeliad from the northern coastal dune scrubland in Yucatan, Mexico

“…Temperature regulates most of the basic aspects of cell metabolism; high temperatures denature enzymes and lower temperatures freeze tissues and damage cell membranes (Palta et al, 1993;Pastenes and Horton, 1996). Furthermore, most plants grow best when temperatures fluctuate at least a 6 to 7 ºC between day and night (Lüttge, 2004).…”