Submitted to: Plant Physiology
Publication Type: Review Article
Publication Acceptance Date: July 14, 1999
Publication Date: N/A
Interpretive Summary: When exposed to environmental stress, such as temperature extremes, poisons, or attack by pathogens, plant cells respond with a large-scale shift in behavior. Normal, "house-keeping" activities are turned off and a small number of stress-related functions are turned on. Included in the stress response are the production of specific chemicals. It has long been assumed that these stress chemicals were able to function individually. A variety of methods were employed to identify some of the stress chemicals produced by corn, and it was shown that many of the chemicals function together in a complex mixture rather than as individuals. This information will be important to researchers in their attempts to increase agricultural productivity by altering the control of plant cell respiration, and to other plant scientists who will try to design more efficient crop plants through either classical breeding or biotechnology.
Technical Abstract: Information necessary to direct the folding of polypeptide chains into a final functional conformation is contained within the primary amino acid sequence. Most proteins, however, require assistance in folding under physiological conditions. This assistance can be supplied by stress proteins/molecular chaperones, and by specific enzymes called folding catalysts. Three recombinant Arabidopsis thaliana stress proteins were demonstrated to function together as a complex in the suppression of thermal denaturation of the model cytoplasmic protein malate dehydrogenase. A model of chaperone function in plant cells was constructed based upon measurements made using this in vitro assay plus previously described protein structural features.