Contact Information

Dr. Rajinder Dhindsa
Biology Department, McGill University
1205 ave Docteur Penfield
Room N3/11B
Montreal, Quebec, Canada H3A 1B1

Tel.: (514)-398-6423
FAX: (514)-398-5069

Research Interests

Molecular stress biology of plants. Low temperature signal transduction, calcium, protein phosphorylation, protein kinases, protein phosphatases, calcium, calcium channels, cold-regulated gene expression and freezing tolerance.

Molecular Biology of Low Temperature Sensing and Freezing Tolerance in Plants

Low temperatures severely limit the distribution and productivity of plants. Different varieties of crop plants vary in their tolerance to cold and any increase in such tolerance would have a major beneficial impact on agricultural production. Therefore, improving the chilling/freezing tolerance of major crop plants is of strategic importance to Canadian agricultural economy. Studies of cytogenetics and the practice of conventional plant breeding have firmly established the genetic basis and multigenic nature of cold tolerance. During the past 10 years, cold-regulated genes have been identified in many plants.

Studies in my laboratory have focused on: i) Isolation and characterization of cold acclimation-specific (cas) genes ii) Transfer of these genes to homologous and heterologous systems in order to study their regulation and function, and to enhance freezing tolerance of the host species; and iii) mechanisms by which plants sense the low temperature signal and transduce it into biochemical processes leading to the expression of cas genes. In low temperature signal transduction we are exploring the relationship between membrane fluidity and calcium influx and relative roles of protein kinases and protein phosphatases.

Selected Publications

  1. Shawky, A., Fayed, A., Heakle, M.Y., Dhindsa, R. & Mansour, A.  The existence and regulation of heat-responsive HSP27 and MAPAPK2 proteins in Tobacco cells.  Zagazig J. Agric. Res., v.32 no. (2), 2005, pp. 491-499.
  2. Sangwan, V. & Dhindsa, R.S. 2002. In vivo and in vitro activation of temperature-responsive Plant Map Kinases.  FEBS Letters, v. 531, pp. 561-564.
  3. Sangwan, V., Orvar, B.L. & Dhindsa, R.S. Early events during low temperature signaling. In:Plant Cold Hardiness: Gene expression and genetic engineering, (eds.) P.H. Li, and T. Palva, Plenum Press, 2002, pp. 43-53.
  4. Sangwan, V., Orvar, B.L., Beyerly, J., Hirt, H. and Dhindsa, R. S. 2002. Opposite changes in membrane fluidity mimic cold and heat stress activation of distinct plant MAP kinase pathways. The Plant Journal 31: 629-638.
  5. Sangwan, V., Foulds, I., Singh, J. and Dhindsa, R. S. 2001. Cold activation of Brassica napus BN115 promoter is mediated by structural changes in membranes and cytoskeleton, and requires Ca2+ influx. The Plant Journal 27: 1-12.
  6. Orvar, B. L., Sangwan, V., Omann, F. and Dhindsa, R. S. 2000. Early steps in cold sensing by plant cells: the role of actin cytoskeleton and membrane fluidity. The Plant Journal 23: 785-794.
  7. Monroy, A., Sangwan, V. and Dhindsa, R. S. 1998. Low temperature signal transduction during cold acclimation: protein phosphatase 2A as an early target for cold-inactivation. The Plant Journal 13: 653-660
  8. Dhindsa, R. S., Monroy, A. F. Sangwan, V., Kawczynski, W. and Labbé, E. 1998. Low temperature signal transduction during cold acclimation of alfalfa. In: Plant Cold Hardiness: Molecular Biology, Biochemistry and Physiology ( P.H. Li and T.H.H. Chen, Eds.) , Plenum Press, NewYork, pp. 15-28.
  9. Monroy, A. F., Labbé, E. and Dhindsa, R. S. (1997). Low temperature perception in plants: Effects of cold on protein phosphorylation in cell-free extracts. FEBS Letters 410: 206-209.
  10. Tahtiharju, S., Sangwan, V., Monroy, A. F., Dhindsa, R. S. and Borg, M. 1997. The induction of kin genes in cold acclimating Arabidopsis thaliana: Evidence for a role of calcium. Planta 203: 442-447.
  11. Monroy, A. F. and Dhindsa, R. S. (1995) Low temperature signal transduction: The induction of cold acclimation-specific genes of alfalfa by calcium at 25°C. Plant Cell 7: 321-331.
  12. Dhindsa, R. S. and Monroy, A. F. 1994. Low temperature signal transduction and cold-induced gene expression and cold acclimation: Multiple roles of low temperature. In: Molecular and Cellular Mechanisms of Stress Tolerance in Plants (J.H. Cherry, Ed.) NATO ASI Series, Vol H86 Springer-Verlag, pp. 501-514.
  13. Monroy, A. F., Sarhan, F. and Dhindsa, R. S. (1993) Cold-induced changes in freezing tolerance, protein phosphorylation, and gene expression: Evidence for a role of calcium. Plant Physiology 102:1227-1235.
  14. Monroy, A. F., Castonguay, Y., Laberge, S., Sarhan, F., Vezina, L. P. and Dhindsa, R. S. 1993. A new cold-induced alfalfa gene is associated with enhanced hardening at subzero temperature. Plant Physiol. 102: 873-879.
  15. Wolfraim, L. A., Langis, R., Tyson, H. and Dhindsa, R. S. 1993. Complementary DNA sequence, expression, and transcript stability of a cold acclimation-specific gene, cas18, of alfalfa (Medicago falcata) cells. Plant Physiol. 101: 1275-1282.

Last update: Aug. 17/2009