Storage hunters
Plants use lipids for a variety of functions
We get a lot of our lipids from plants: sunflower oil, olive oil, nuts and seeds are all good sources of fats. But why do plants need fats? They don’t have nerve cells, they can’t feel the cold and they make their own food (glucose) by photosynthesis.
Well, they need phospholipids to make up their cell membranes, as animals do. Another important function of lipids in plants is as the energy store in seeds. Germinating seedlings cannot make their own sugars through photosynthesis, so they rely on stored lipid droplets to fuel their growth.
Other functions of lipids include making hormones and the formation of the cuticle (the waxy, waterproof coating for leaves and stems) and the exine (a tough, stiff coating for pollen grains).
Some genes involved in fat storage in plants have equivalents in yeast and mammals. In humans, mutations in the gene that controls synthesis of the molecule seipin can cause a disorder where fat is stored around the muscles instead of in adipose tissues. The flowering plant Arabidopsis has versions of this gene, suggesting that plants could help us to understand more about human disease.
Lead image:Maize seed.
International Maize and Wheat Improvement Center/Flickr CC BY NC
References
- Biogenesis and functions of lipid droplets in plants (2012)
- Plant phospholipid signaling: ‘in a nutshell’ (2009) [PDF]
- Information sheet on seipin
- Beradinelli–Seip congenital lipodystrophy
Downloadable resources
- Storage hunters PDF [PDF 85KB]
Related resources
Fatty acid primer
A quick guide to how the carbon bonds in fatty acids can be arranged
Fat on the brain
We need fats for our nervous system
Storing fat
How we make triglycerides – one way that the body stores fat