Dr. C. Peter Constabel

Research

• Plant biochemistry, genomics and molecular biology; chemical ecology and plant stress adaptation; bioactive phenolics and tannins

My research program aims to understand how plants use phytochemicals to defend against herbivores and pathogens and adapt to environmental stresses. Research in my lab focusses on plant tannins and other bioactive phenolic phytochemicals, which we study in poplar and aspen. We are interested in understanding how these are synthesized, regulated, and how they help adapt poplar trees to their environment.
A major advantage of studying these questions in Populus is that it can be genetically transformed, so that we can create transgenic poplar plants to test the functions of specific genes. We use the tools of biochemistry, molecular biology, genomics, and plant transformation to answer the following fundamental questions.

• What is the adaptive role of tannins in trees, in particular in roots? Are they important for pathogen defense or mycorrhizal interactions?
• How do MYB and other transcription factors regulate biosynthesis of tannins and other phenolics? What is the impact of MYB knock-outs on tannin accumulation and tree adaptation?
• How are the salicinoid phenolic glycosides synthesized? Can we identify enzymes for this as yet unelucidated pathway?

My lab has also studied phenolic plant chemicals in red alder, which synthesize diarylheptanoid phenolics. We have also studied the synthesis and functions of tannins in fruit, in particular in blueberry and salalberry, traditionally used local berries. They contain very high amounts of tannins, which have beneficial effects in the diet and can prevent chronic disease.