Expression of the maize ZmGF14-6 gene in rice confers tolerance to drought stress while enhancing susceptibility to pathogen infection.
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.
Department of Molecular Genetics, Centre for Research in Agricultural Genomics CSIC-IRTA-UAB-UB, Parc de Recerca UAB, Edifici CRAG, Campus UAB, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain.
Sonia
S
Campo
Cristina
C
Peris-Peris
Laura
L
Montesinos
Gisela
G
Peñas
Joaquima
J
Messeguer
Blanca
B
San Segundo
D048948:14-3-3 Proteins / Q000235:genetics / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D004198:Disease Susceptibility / Q000276:immunology* / Q000382:microbiology; D055864:Droughts; D005670:Fusarium / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D020082:Magnaporthe / Q000502:physiology; D019697:Onions / Q000235:genetics / Q000378:metabolism; D012275:Oryza / Q000235:genetics / Q000276:immunology* / Q000382:microbiology / Q000502:physiology; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000502:physiology; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D011994:Recombinant Proteins / Q000302:isolation & purification; D036226:Seedlings / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation; D003313:Zea mays / Q000235:genetics*
D048948:14-3-3 Proteins; D018076:DNA, Complementary; D010940:Plant Proteins; D018749:RNA, Plant; D011994:Recombinant Proteins; D014157:Transcription Factors; D012965:Sodium Chloride