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Engineering Crops to Better Cope With Global Warming
Fu, J., Momcilovic, I., Clemente, T.E., Nersesian, N., Trick, H.N. and Ristic, Z. 2008. Heterologous expression of a plastid EF-Tu reduces protein thermal aggregation and enhances CO2 fixation in wheat (Triticum aestivum) following heat stress. Plant Molecular Biology 68: 277-288.

The authors set the stage for describing and reporting the findings of their important new study by noting that "heat stress is a major constraint to wheat production and negatively impacts grain quality, causing tremendous economic losses, and may become a more troublesome factor due to global warming."

What was done
Fu et al., as they describe it, "introduced into wheat the maize gene coding for plastidal EF-Tu [protein synthesis elongation factor]," and they "report on the expression of the transgene, and its effect on thermal aggregation of leaf proteins in transgenic plants," as well as "the heat stability of photosynthetic membranes (thylakoids) and the rate of CO2 fixation in young transgenic plants following exposure to heat stress."

What was learned
In reference to what they call "the first demonstration of the introduction of a plastidal EF-Tu in plants that leads to protection against heat injury and enhanced photosynthesis after heat stress," the six U.S. researchers write that this act "led to improved protection of leaf proteins against thermal aggregation, reduced damage to thylakoid membranes and enhanced photosynthetic capability following exposure to heat stress," which results, in their words, "support the concept that EF-Tu ameliorates negative effects of heat stress by acting as a molecular chaperone." They also write that their work constitutes "the first demonstration that a gene other than HSP [heat shock protein] gene can be used for improvement of heat tolerance and that the improvement is possible in a species that has a complex genome, hexaploid wheat."

What it means
Fu et al. conclude their report by stating that their results "strongly suggest that heat tolerance of wheat, and possibly other crop plants, can be improved by modulating expression of plastidal EF-Tu and/or by selection of genotypes with increased endogenous levels of this protein." Hence, there is reason to believe that humanity's major crops could well be genetically "inoculated" against the deleterious consequences of potential future global warming, irrespective of whatever its cause or causes may be.

Reviewed 5 November 2008