Hargurdeep (Deep) Saini
deep [dot] saini (at)utoronto [dot] ca
Department of Biology
University of Toronto at Mississauga
3359 Mississauga Road North
Canada L5L 1C6
My general research interests encompass the physiological, biochemical and molecular responses of plants to environmental stresses, defense mechanisms in plants and the application of biotechnology to improve plant tolerance against adverse environments. Our approach to research is multi-disciplinary and employs a wide array of analytical techniques and genetic manipulations to probe biological processes from cellular to whole-plant levels.
Our current research is focused on the roles of thiol and halide methylation in plant metabolism and stress tolerance:
- Thiol methylation: Several plant families, notably the Brassicaceae, accumulate sulfur-containing thioglucosides, glucosinolates, which, upon tissue-disruption through herbivory or infection, are degraded into a variety of toxic, defensive products. We have discovered thiol methyl transferase enzymes that apparently neutralize the products of glucosinolate hydrolysis once their defensive role has been accomplished (Fig. 1). We are investigating the biochemical and molecular regulation, cellular organization, and biological functions of these enzymes.
- Halide methylation: Vast quantities of chloromethane (CH3Cl) are released into the atmosphere by biological sources. Production of CH3Cl via enzymatic methylation of Cl– ions has been viewed as a Cl– detoxification mechanism in saline environments. Thiol methyl transferase enzymes are also capable of methylating halides, including Cl–. We have isolated the genes encoding these enzymes and introduced these into plants that normally do not methylate halides. The efficiency of transgenic plants to methylate chloride, its implications for chloride detoxification and salinity tolerance, and its potential impact on atmospheric chloromethane budget are being evaluated.