Expression of the maize ZmGF14-6 gene in rice confers tolerance to drought stress while enhancing susceptibility to pathogen infection

• Published in: Journal of experimental botany Vol. 63; no. 2; pp. 983 - 999
• Main Authors: CAMPO, Sonia, PERIS-PERIS, Cristina, MONTESINOS, Laura, PENAS, Gisela, MESSEGUER, Joaquima, SAN SEGUNDO, Blanca
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01-01-2012
• Subjects: 14-3-3 Proteins - genetics; 14-3-3 Proteins - metabolism; Biological and medical sciences; Disease Susceptibility - immunology; Disease Susceptibility - microbiology; DNA, Complementary - genetics; Droughts; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Fusarium - physiology; Gene Expression Regulation, Plant - physiology; Magnaporthe - physiology; Onions - genetics; Onions - metabolism; Oryza - genetics; Oryza - immunology; Oryza - microbiology; Oryza - physiology; Phytopathology. Animal pests. Plant and forest protection; Plant Diseases - immunology; Plant Diseases - microbiology; Plant physiology and development; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Roots - genetics; Plant Roots - immunology; Plant Roots - microbiology; Plant Roots - physiology; Plants, Genetically Modified; Promoter Regions, Genetic - genetics; Recombinant Proteins - isolation & purification; Research Papers; RNA, Plant - genetics; Seedlings - genetics; Seedlings - immunology; Seedlings - microbiology; Seedlings - physiology; Signal Transduction - physiology; Sodium Chloride - pharmacology; Stress, Physiological - physiology; Transcription Factors - genetics; Transcription Factors - metabolism; Up-Regulation; Zea mays - genetics; 14-3-3 proteins; early endosomes; Monocotyledones; Plant pathogen; Environmental factor; Water stress; Cereal crop; Abiotic factor; abiotic stress; Fungi; Promoter; Oryza sativa; Gene; Gramineae; Pathogenic; Angiospermae; Botany; Fungi Imperfecti; ZmPR4 promoter; Drought; Endosome; Biotic factor; Ascomycota; Zea mays; Magnaporthe oryzae; Tolerance; Protein; Infection; Fusarium verticillioides; biotic stress; Spermatophyta
• ISSN: 0022-0957; 1460-2431
• DOI: 10.1093/jxb/err328

14-3-3 proteins are found in all eukaryotes where they act as regulators of diverse signalling pathways associated with a wide range of biological processes. In this study the functional characterization of the ZmGF14-6 gene encoding a maize 14-3-3 protein is reported. Gene expression analyses indicated that ZmGF14-6 is up-regulated by fungal infection and salt treatment in maize plants, whereas its expression is down-regulated by drought stress. It is reported that rice plants constitutively expressing ZmGF14-6 displayed enhanced tolerance to drought stress which was accompanied by a stronger induction of drought-associated rice genes. However, rice plants expressing ZmGF14-6 either in a constitutive or under a pathogen-inducible regime showed a higher susceptibility to infection by the fungal pathogens Fusarium verticillioides and Magnaporthe oryzae. Under infection conditions, a lower intensity in the expression of defence-related genes occurred in ZmGF14-6 rice plants. These findings support that ZmGF14-6 positively regulates drought tolerance in transgenic rice while negatively modulating the plant defence response to pathogen infection. Transient expression assays of fluorescently labelled ZmGF14-6 protein in onion epidermal cells revealed a widespread distribution of ZmGF14-6 in the cytoplasm and nucleus. Additionally, colocalization experiments of fluorescently labelled ZmGF14-6 with organelle markers, in combination with cell labelling with the endocytic tracer FM4-64, revealed a subcellular localization of ZmGF14-6 in the early endosomes. Taken together, these results improve our understanding of the role of ZmGF14-6 in stress signalling pathways, while indicating that ZmGF14-6 inversely regulates the plant response to biotic and abiotic stresses.