Using plants as models for disease

Some proteins are remarkably well conserved in both plants and animals. Not only does this demonstrate how closely related all living things on Earth are, but it also opens up new avenues of research. Proving that point, Wendy Peer of Purdue University successfully rescued plants deficient in one class of enzymes by giving them a mammalian equivalent.

She and her team knocked out the APM1 protein in the small flowering plant Arabidopsis thaliana. APM1 is one of a class of M1 aminopeptidases that, in humans, are responsible for trimming specific amino acids off of peptide chains, thereby either activating or deactivating those proteins. In addition, the M1 enzymes are thought to rid cells of excess proteins that may be responsible for Alzheimer's disease. Although not as well understood in plants, APM1 is essential for normal plant growth and reproduction.

Peer and her colleagues treated Arabidopsis plants with an APM1 inhibitor, destroying the plants’ natural enzyme. The researchers then genetically altered the plants to produce mammalian M1 proteins. The mammalian proteins effectively rescued the plants. In other words, the mammalian proteins were similar enough to the plant proteins to do the exact same job in the plant cells.

The ability to choose plant models rather than animal models would be a welcome addition for researchers. Not only are plants relatively easy to maintain, but working with them would also bypass many ethical questions faced by both scientists and the public.