Functional genomics of low temperature tolerance in crop plants

Genome Canada and Genome Québec.

Applicants: Fathey Sarhan (UQAM), Jean-François Laliberté (INRS), Patrick Gulick (Concordia), Luc Varin (Concordia).

The current proposal focuses on the identification and characterization of the genetic mechanisms that are central to the induction and regulation of low-temperature (LT) tolerance at the whole plant and molecular level.

LT tolerance has been identified as a "crucial strategic" trait for Canadian crops. LT damage is an abiotic stress of special concern to Canadian agriculture because of our short growing season and severe winters. The identification of genes contributing to frost tolerance and the understanding of their regulation will provide new opportunities for the exploitation of the genetic potential in a wide range of species by expanding our ability to utilize traditional plant breeding methods. The products (proteins) of isolated LT genes also have an application for the production of natural organic compounds for use in LT storage of industrial and food products.

Genes encoding structural proteins, osmolyte-producing enzymes, oxidative stress scavenging enzymes, lipid desaturases and gene regulators can be used to produce transgenic crops and microorganisms. Specific objectives are outlined as follows:

1. Eighty thousand EST sequences will be generated for wheat. Subtracted cDNA libraries will be used to reduce the degree of duplication in the sequencing. We expect to isolate 10,000 unique ESTs.
2. Ten thousand spot microarrays will be generated using the wheat cDNA clones from this program. We expect to expand these microarrays to 20,000 clones through international cooperation. Multiple comparisons will serve to evaluate the relative importance of candidate genes for their contribution to stress tolerance. We anticipate that the microarrays of wheat will be suitable for comparison of gene expression in related species.
3. Transgenic plants will be developed in cereals and Arabidopsis to validate the effectiveness of candidate genes for improving LT tolerance, characterize stress responsive gene promoters, and generate "promoter: reporter" lines to be used for multinational screening for regulatory genes.