Ordered rise and disordered fall: dynamic changes of membrane lipids during girdling-induced tree mortality in Populus yunnanensis.

Understanding the mechanisms behind drought-induced tree mortality is crucial for predicting the impact of global climate change on forests. We studied the mechanism at the cellular level in Populus yunnanensis by profiling membrane lipid molecules in leaves, branch phloem, top and bottom trunk phloem under trunk-girdling-induced drought conditions. We found that both lipid composition and content changed, depending on the tree's tissue positions and the progression of the girdling effect.

Characterisation of manganese toxicity tolerance in .

Manganese (Mn) contamination limits the production and quality of crops, and affects human health by disrupting the food chain. is a pioneer species of Brassicaceae found in mining areas, and has the ability to accumulate heavy metals. However, little is known about the genetic mechanisms of Mn tolerance in .

Polar auxin transport May Be responsive to specific features of flavonoid structure.

Polar auxin transport (PAT) is essential to control root growth. Flavonoids are widely thought to be PAT inhibitors leading to short root developments. However, we found that the flavonoids scutellarin and scutellarein, which both have a 6-hydroxyl group unlike the structure of known flavonoid-PAT-inhibitors, promote PAT in roots.

Submergence induced changes of molecular species in membrane lipids in .

The composition of membrane lipids is sensitive to environmental stresses. Submergence is a type of stress often encountered by plants. However, how the molecular species of membrane lipids respond to submergence has not yet been characterised.

Lipid profiling demonstrates that suppressing Arabidopsis phospholipase Dδ retards ABA-promoted leaf senescence by attenuating lipid degradation.

Senescence is the last phase of the plant life cycle and has an important role in plant development. Degradation of membrane lipids is an essential process during leaf senescence. Several studies have reported fundamental changes in membrane lipids and phospholipase D (PLD) activity as leaves senesce.

Plant adaptation to frequent alterations between high and low temperatures: remodelling of membrane lipids and maintenance of unsaturation levels.

One major strategy by which plants adapt to temperature change is to decrease the degree of unsaturation of membrane lipids under high temperature and increase it under low temperature. We hypothesize that this strategy cannot be adopted by plants in ecosystems and environments with frequent alterations between high and low temperatures, because changes in lipid unsaturation are complex and require large energy inputs. To test this hypothesis, we used a lipidomics approach to profile changes in molecular species of membrane glycerolipids in two plant species sampled from alpine screes and in another two plant species grown in a growth chamber, with the temperature cycling daily between heat and freezing.