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Induction of Proteins in Response to Biotic and
Abiotic Stresses
Timothy S. Artlip and Michael E. Wisniewski
U.S. Department of Agriculture–Agriculture Research Service, Kearneysville, West Virginia
657I. INTRODUCTION
The responses of plants and crops to environmental stresses generally involve some alteration in protein
synthesis. Protein-based responses include qualitative changes in general protein synthesis or the up- or
down-regulation of specific proteins. These changes depend on the nature, duration, and severity of the
stress. The primary focus of this chapter will be on proteins that are induced or increase in abundance in
response to an environmental stress. Although decreases of specific proteins can be physiologically sig-
nificant, most research has centered on inducible proteins on the assumption that they confer some pro-
tection to the organism that leads to increased survival.
Two broad areas of stress will be considered: biotic (pathogen, herbivore) and abiotic (physical en-
vironment). Each confronts the plant with a particular set of challenges. In general, biotic stresses engen-
der active structural and biochemical responses to herbivory or microbial attack. Abiotic stresses, con-
versely, induce the plant to adjust its metabolism (acclimation) or alter its pattern of growth in order to
avoid sustained exposure to the stress. As will be seen, biotic and abiotic stresses sometimes result in sim-
ilar plant responses and some degree of commonality is evident. Here, the biotic stresses are considered
first.
It must be noted that because of the rapid, continuing progress in the field, a comprehensive treatise
on all the relevant literature is beyond the scope of this chapter. Instead, this chapter represents a general
overview, and the reader is encouraged to seek out the appropriate references for further information.
II. BIOTIC STRESS
A. General Concepts
Interactions between plants and most pathogens are compatible or incompatible, depending on gene-for-
gene interactions between the plant and the pathogen. The gene-for-gene interactions are generally be-
tween plasma membrane–bound receptors (R or resistance-gene products) and products that may be ex-
pressed by the pathogen. A pathogen-expressed product that is recognized by a plant R-gene product is
termed an avirulent one, and the interaction results in an incompatible interaction between the plant and
the pathogen [1]. This in turn leads to both local and systemic acquired resistance in the plant (see later).