Molecular Chaperones Confer Abiotic Stress Tolerance in GM Plants

Plants with improved performance under drought conditions have been achieved through multiple transgenic approaches, such as the use of genes coding for osmoprotectants (mostly sugar alcohols), zwitterionic compounds and protein protectants. The transgenic plants performed well under water-deficit stress, at least in laboratories and greenhouses. Nonetheless, the lab experiments demonstrate that plants are amenable to improved stress tolerance through multiple mechanisms of action.

Scientists from Monsanto Company have demonstrated that bacterial cold shock proteins (Csp) can also confer improved stress adaptation to multiple plant species. Csp belongs to a family of molecular chaperones that assist ribonucleic acids (RNA). RNA tends to be trapped in misfolded forms, and CSP proteins, acting as chaperones, can resolve these structures.

Transgenic rice and maize plants expressing Csp proteins (from E. coli and B. subtilis) manifest improved stress tolerance for a number of abiotic stresses, including cold, heat, and water deficits. Importantly, the improvements in water-limited field trials were not associated with yield penalty in high-yielding environments.

The paper published by the journal Plant Physiology is available at http://www.plantphysiol.org/cgi/content/full/147/2/446