ABSTRACT
Plants have evolved complex molecular, cellular and physiological mechanisms to respond to environmental stressors. Because of the inherent complexity of this response, genetic manipulation to substantially improve water deficit tolerance, particularly in agricultural crops, has been largely unsuccessful, as the improvements are frequently accompanied by slower growth and delayed reproduction. Here, we ectopically express two abiotic stress-responsive bZIP AREB/ABF transcription factor orthologs, Arabidopsis ABF3 and Gossypium hirsutum ABF2D, in G. hirsutum, to compare the effects of exogenous and endogenous AREB/ABF transgene overexpression on dehydration resilience. Our results show that ectopic expression of each of these orthologs increases dehydration resilience, although these increases are accompanied by slower growth. These phenotypic effects are proportional to the ectopic expression level in the GhABF2D transgenic plants, while the phenotypes of all of the AtABF3 transgenic plants are similar, largely independent of ectopic expression level, possibly indicating differential post-transcriptional regulation of these transgenes. Our results indicate that overexpression of exogenous and endogenous ABF homologs in G. hirsutum substantially increases drought resilience, primarily through stomatal regulation, negatively impacting transpiration and photosynthetic productivity.
Subject(s)
Arabidopsis Proteins/metabolism , Basic-Leucine Zipper Transcription Factors/metabolism , Gossypium/physiology , Transcription Factors/metabolism , Arabidopsis Proteins/genetics , Basic-Leucine Zipper Transcription Factors/genetics , Crops, Agricultural , Droughts , Ectopic Gene Expression , Gossypium/genetics , Phenotype , Photosynthesis , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Stomata/genetics , Plant Stomata/physiology , Plant Transpiration/physiology , Plants, Genetically Modified , Stress, Physiological , Transcription Factors/geneticsABSTRACT
Sucrose phosphate synthase (SPS) catalyzes the first step in the synthesis of sucrose in photosynthetic tissues. We characterized the expression of three different isoforms of SPS belonging to two different SPS gene families in alfalfa (Medicago sativa L.), a previously identified SPS (MsSPSA) and two novel isoforms belonging to class B (MsSPSB and MsSPSB3). While MsSPSA showed nodule-enhanced expression, both MsSPSB genes exhibited leaf-enhanced expression. Alfalfa leaf and nodule SPS enzymes showed differences in chromatographic and electrophoretic migration and differences in V (max) and allosteric regulation. The root nodules in legume plants are a strong sink for photosynthates with its need for ATP, reducing power and carbon skeletons for dinitrogen fixation and ammonia assimilation. The expression of genes encoding SPS and other key enzymes in sucrose metabolism, sucrose phosphate phosphatase and sucrose synthase, was analyzed in the leaves and nodules of plants inoculated with Sinorhizobium meliloti. Based on the expression pattern of these genes, the properties of the SPS isoforms and the concentration of starch and soluble sugars in nodules induced by a wild type and a nitrogen fixation deficient strain, we propose that SPS has an important role in the control of carbon flux into different metabolic pathways in the symbiotic nodules.
Subject(s)
Carbon/metabolism , Gene Expression Regulation, Plant , Glucosyltransferases/genetics , Medicago sativa/enzymology , Medicago sativa/genetics , Nitrogen/metabolism , Root Nodules, Plant/enzymology , Allosteric Regulation/genetics , Blotting, Western , Carbohydrate Metabolism/genetics , Chromatography, Ion Exchange , Gene Expression Profiling , Genes, Plant/genetics , Medicago sativa/microbiology , Multigene Family , Nitrogen Fixation/genetics , Plant Leaves/enzymology , Plant Leaves/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Root Nodules, Plant/genetics , Root Nodules, Plant/microbiology , Sinorhizobium meliloti/physiology , Solubility , Starch/metabolism , Symbiosis/geneticsABSTRACT
Gibberellic acid (GA) is both necessary and sufficient to promote fiber elongation in cultured fertilized ovules of the upland cotton variety Coker 312. This is likely due to the temporal and spatial regulation of GA biosynthesis, perception, and subsequent signal transduction that leads to alterations in gene expression and morphology. Our results indicate that the initiation of fiber elongation by the application of GA to cultured ovules corresponds with increased expression of genes that encode xyloglucan endotransglycosylase/hydrolase (XTH) and expansin (EXP) that are involved in promoting cell elongation. To gain a better understanding of the GA signaling components in cotton, that lead to such changes in gene expression, two GA receptor genes (GhGID1a and GhGID1b) and two DELLA protein genes (GhSLR1a and GhSLR1b) that are orthologous to the rice GA receptor (GID1) and the rice DELLA gene (SLR1), respectively, were characterized. Similar to the GA biosynthetic genes, expression of GhGID1a and GhGID1b is under the negative regulation by GA while GA positively regulates GhSLR1a. Recombinant GST-GhGID1s showed GA-binding activity in vitro that was augmented in the presence of GhSLR1a, GhSLR1b, or rice SLR1, indicating complex formation between the receptors and repressor proteins. This was further supported by the GA-dependent interaction of these proteins in yeast cells. Ectopic expression of the GhGID1a in the rice gid1-3 mutant plants rescued the GA-insensitive dwarf phenotype, which demonstrates that it is a functional GA receptor. Furthermore, ectopic expression of GhSLR1b in wild type Arabidopsis led to reduced growth and upregulated expression of DELLA-responsive genes.
Subject(s)
Gibberellins/pharmacology , Gossypium/metabolism , Plant Proteins/metabolism , Signal Transduction/drug effects , Amino Acid Sequence , Electrophoresis, Polyacrylamide Gel , Gene Expression Regulation, Plant/drug effects , Gossypium/genetics , Molecular Sequence Data , Oryza/genetics , Oryza/metabolism , Plant Growth Regulators/pharmacology , Plant Proteins/genetics , Plant Proteins/physiology , Protein Binding , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid , Signal Transduction/genetics , Signal Transduction/physiology , Two-Hybrid System TechniquesABSTRACT
No disponible
Subject(s)
Male , Female , Adult , Aged , Humans , Urine , Anticoagulants , Urologic Diseases , Treatment Outcome , Tomography, X-Ray Computed , Drainage , Venous Thrombosis , Gastroscopy , Gastritis, Hypertrophic , Gastritis, Atrophic , Enterochromaffin Cells , Gastritis, HypertrophicSubject(s)
Fever/microbiology , Legionellosis/diagnosis , Adult , Humans , Legionellosis/complications , MaleABSTRACT
OBJECTIVE: Infective endocarditis (IE) in injection drug users (IDU) have a special etiologic, epidemiological and clinical characteristics different to IE in the general population. The clinical and evolutive features of a group of IE in IVD are reported. METHODS: A retrospective analysis was made of 34 episodes (24 patients) of IE in IDU in the Catagena Area (Murcia, Sapin). RESULTS: A total 34 episodes, 18 was males (75%) and 6 (25%) females with a age media of 26.1 years (DE, 4.3). Eighty-four percents were infected with human immunodeficiency virus. The location of IE was right-side in 26 (73%), left-side in 7 cases (18%) and right-left in one (2%). Staphylocococcus aureus was isolated in 31 cases (91%), it was meticillin-resistant in 4 cases (13%); Pseudomonas aeruginosa, and Streptococcus equisimilis was isolated in one case each. Fever was present in 33 patients (97%) and more than half were cough, pleuritic chest pain and expectoration. Twenty-five patients with right IE has chest X-ray abnormal, specially nodules-infiltrates pulmonary. Vegetations were not observe in 7 (21%) occasions by transthoracic echocardiography. In six of 8 patients with left-side IE present a cerebri embolisms. Two patients with left IE death (21%). The rate of successful therapy in the right-side IE treated during 2 or 4 weeks were 100%. CONCLUSIONS: The IE in IDU is a entity produced mainly by S. aureus, affect preferentially a right-side cavities and the prognosis is generally good.
Subject(s)
Endocarditis, Bacterial/diagnosis , Substance Abuse, Intravenous/complications , Adult , Endocarditis, Bacterial/etiology , Female , Humans , Male , Retrospective StudiesABSTRACT
Objetivo: La endocarditis infecciosa (EI) en usuarios de drogas por vía parenteral (UDVP) tiene unas características etiológicas, epidemiológicas y clínicas diferentes a la EI en la población general. El objetivo del trabajo es describir los aspectos clínicos y evolutivos de la EI en UDVP. Método: Se revisa de forma retrospectiva 34 episodios (en 24 pacientes) de EI en UDVP del área de Cartagena (Murcia). Resultados: De los 34 episodios, 18 eran varones (75 por ciento) y 6 (25 por ciento) mujeres con una edad media de 26,1 años (DE,4,3). El 84 por ciento tenían infección por el virus de la inmunodeficiencia humana. La localización de la endocarditis fue derecha en 26 (73 por ciento) episodios, izquierda en 7 (18 por ciento) y mixta en 1 (2 por ciento). Staphylocococcus aureus se aisló en 31 ocasiones (91 por ciento), siendo resistente in vitro a cloxacilina en 4 ocasiones (13 por ciento); Pseudomonas aeruginosa y Streptococcus equisimilis en una ocasión cada uno. Se constató fiebre en 33 pacientes (97 por ciento) y en más de la mitad tos, dolor pleurítico y/o expectoración. Veinticinco pacientes con EI derecha tenía alteraciones en la radiografía de tórax, especialmente infiltrados-nódulos pulmonares. En la ecocardiografía transtorácica no se vieron vegetaciones en 7 ocasiones (21 por ciento). Seis de los 8 pacientes con EI izquierda presentaron embolismos cerebrales. Fallecieron 2 pacientes (6 por ciento), ambos con EI izquierda. La tasa de curación de las EI derechas tratadas tanto 2 como 4 semanas fue del 100 por ciento. Conclusión: La EI en UDVP es una entidad producida principalmente por S. aureus con predominio de afectación en cavidades derechas y con pronóstico a corto plazo generalmente bueno (AU)
Subject(s)
Adult , Female , Male , Humans , Endocarditis, Bacterial , Retrospective Studies , Substance Abuse, Intravenous , Endocarditis, Bacterial/diagnosis , Endocarditis, Bacterial/etiology , Substance Abuse, Intravenous/complicationsABSTRACT
185 cases of bacteremia admitted at the internal medicine department of "C.S. Virgen de la Arrixaga" in Murcia from 1977 to 1986, were studied retrospectively. The common infection was significantly associated to Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus A group and Neisseria meningitidis and the nosocomial infection was associated to Klebsiella Pneumoniae, Serratia Marcescens y Pseudomonas aeruginosa, Staphylococcus epidermidis and Enterobacter. We did not find significant differences between the common and nosocomial infection caused by E. Coli and Proteus mirabilis. These factors were associated to an increase of mortality: age greater than 40 years, nosocomial infection, Pseudomonas aeruginosa, other associated rapidly lethal diseases, acute clinical state at the beginning of bacteremia, shock and non-correct antibiotic therapy.
