"The genetics behind variable drug responses is not peculiar to humans but exists also in other branches on the tree of life," Nature Chemical Biology quoted Sean Cutler, an assistant professor of plant cell biology at UC Riverside, as saying.
"We can harness simple organisms to understand more about the genetics and biochemistry of variable drug responses, which could help uncover new factors that contribute to variable drug responses in humans," he added.
Cutler and his colleagues have studied a weedy plant in the mustard family called Arabidopsis thaliana, and discovered a key protein in the plant that creates drug resistance.
He says that the protein, called UGT (UDP-glycosyltransferase), is a member of a family of proteins that also affect drug sensitivity in humans.
"Similar biochemical processes are affecting drug sensitivity in both plants and animals. These similarities suggest that plants can be useful for studying problems of human interest like drug responses," Cutler said.
The researchers screened thousands of drug-like compounds during the study and discovered a new molecule called hypostatin, which acts like a drug in inhibiting plant growth in some Arabidopsis plants.
At the same time, the researchers grew Arabidopsis plants in a solution containing hypostatin, which allowed the plant cells to take up hypostatin.
Cutler's team found that the plants' UGT activates hypostatin by adding a sugar molecule to it.
The researchers also found that hypostatin did not work properly in plants that had a genetically defective UGT because sugar molecules were not added to it, as a result of which the growth of such plants was not affected.
"This mechanism is very similar to that seen in humans, where altered drug sensitivity can occur because of defective or atypical sugar-tagging proteins," Cutler said.
The study was conducted as part of an ongoing research aimed at identifying and characterizing new bioactive compounds in plants.
Cutler has revealed that his team is not contemplating expanding their search for other sugar-activated molecules.