Fusicoccin, 14-3-3 Proteins, and Defense Responses in Tomato Plants

• Published in: Plant physiology (Bethesda) Vol. 119; no. 4; pp. 1243 - 1250
• Main Authors: Roberts, Michael R., Bowles, Dianna J.
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01-04-1999; American Society of Plant Biologists
• Subjects: 14-3-3 Proteins; Amino Acid Sequence; Amino acids; Base Sequence; Biological and medical sciences; Cell Biology and Signal Transduction; Cell membranes; Complementary DNA; DNA Primers - genetics; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Gene Expression - drug effects; Gene expression regulation; Genes; Genes, Plant; Glycosides - pharmacology; Humans; Leaves; Lycopersicon esculentum; Molecular Sequence Data; Pathogens; Pathology, epidemiology, host-fungus relationships. Damages, economic importance; Phylogeny; Phytopathology. Animal pests. Plant and forest protection; Plant cells; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Proteins; Proteins - chemistry; Proteins - genetics; Proteins - metabolism; Sequence Homology, Amino Acid; Solanum lycopersicum - drug effects; Solanum lycopersicum - genetics; Solanum lycopersicum - metabolism; Tomatoes; Toxins; Tyrosine 3-Monooxygenase; Enzyme; Mycotoxin; H; Activation; Structure function relationship; transporting ATPase; Toxin; Binding protein; Signal transduction; Vegetable crop; Gene; Dicotyledones; Angiospermae; Lycopersicon esculentum; Hydrolases; Defense mechanism; Spermatophyta; Elicitation; Solanaceae; Sequencing
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.119.4.1243

Fusicoccin (FC) is a fungal toxin that activates the plant plasma membrane H+-ATPase by binding with 14-3-3 proteins, causing membrane hyperpolarization. Here we report on the effect of FC on a gene-for-gene pathogen-resistance response and show that FC application induces the expression of several genes involved in plant responses to pathogens. Ten members of the FC-binding 14-3-3 protein gene family were isolated from tomato (Lycopersicon esculentum) to characterize their role in defense responses. Sequence analysis is suggestive of common biochemical functions for these tomato 14-3-3 proteins, but their genes showed different expression patterns in leaves after challenges. Different specific subsets of 14-3-3 genes were induced after treatment with FC and during a gene-for-gene resistance response. Possible roles for the H+-ATPase and 14-3-3 proteins in responses to pathogens are discussed.