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51.
Susan C Burleigh Teun van de Laar Corné JM Stroop Wout MJ van Grunsven Niaobh O’Donoghue Pauline M Rudd Gavin P Davey 《BMC biotechnology》2011,11(1):1-17
Background
The photorespiratory nitrogen cycle in C3 plants involves an extensive diversion of carbon and nitrogen away from the direct pathways of assimilation. The liberated ammonia is re-assimilated, but up to 25% of the carbon may be released into the atmosphere as CO2. Because of the loss of CO2 and high energy costs, there has been considerable interest in attempts to decrease the flux through the cycle in C3 plants. Transgenic tobacco plants were generated that contained the genes gcl and hyi from E. coli encoding glyoxylate carboligase (EC 4.1.1.47) and hydroxypyruvate isomerase (EC 5.3.1.22) respectively, targeted to the peroxisomes. It was presumed that the two enzymes could work together and compete with the aminotransferases that convert glyoxylate to glycine, thus avoiding ammonia production in the photorespiratory nitrogen cycle.Results
When grown in ambient air, but not in elevated CO2, the transgenic tobacco lines had a distinctive phenotype of necrotic lesions on the leaves. Three of the six lines chosen for a detailed study contained single copies of the gcl gene, two contained single copies of both the gcl and hyi genes and one line contained multiple copies of both gcl and hyi genes. The gcl protein was detected in the five transgenic lines containing single copies of the gcl gene but hyi protein was not detected in any of the transgenic lines. The content of soluble amino acids including glycine and serine, was generally increased in the transgenic lines growing in air, when compared to the wild type. The content of soluble sugars, glucose, fructose and sucrose in the shoot was decreased in transgenic lines growing in air, consistent with decreased carbon assimilation.Conclusions
Tobacco plants have been generated that produce bacterial glyoxylate carboligase but not hydroxypyruvate isomerase. The transgenic plants exhibit a stress response when exposed to air, suggesting that some glyoxylate is diverted away from conversion to glycine in a deleterious short-circuit of the photorespiratory nitrogen cycle. This diversion in metabolism gave rise to increased concentrations of amino acids, in particular glutamine and asparagine in the leaves and a decrease of soluble sugars. 相似文献52.
53.
A Luquita L Urli MJ Svetaz AM Gennaro ME Giorgetti G Pistone R Volpintesta S Palatnik M Rasia 《Journal of biomedical science》2010,17(1):8
Background
Hyaluronic acid (HA) is present in many tissues; its presence in serum may be related to certain inflammatory conditions, tissue damage, sepsis, liver malfunction and some malignancies. In the present work, our goal was to investigate the significance of hyaluronic acid effect on erythrocyte flow properties. Therefore we performed in vitro experiments incubating red blood cells (RBCs) with several HA concentrations. Afterwards, in order to corroborate the pathophysiological significance of the results obtained, we replicated the in vitro experiment with ex vivo RBCs from diagnosed rheumatoid arthritis (RA) patients, a serum HA-increasing pathology. 相似文献54.
A monoclonal antibody specific for avian early myogenic cells and differentiated muscle 总被引:2,自引:0,他引:2
A monoclonal antibody raised in mouse in response to homogenates of Remark ganglia and dorsal mesentery of chicken embryos was found to exhibit a unique reactivity towards myogenic cells, heart, striated muscles, and smooth muscles in chicken and quail. Indirect immunofluorescence assays were performed at different stages of chicken and quail embryonic development and, after hatching, on tissue sections and cultured cells. They revealed that the cytoplasmic marker recognized by 13F4 is expressed in early embryonic heart, in somitic myotome (from stage 14 onward), in the skeletal muscles in limbs and trunk, in all muscles in the head and the branchial arches, in the smooth muscles of the digestive tract and blood vessels. In myofibrils of striated muscles, the antigen is localized in the Z lines. The antigenicity of the molecule recognized by 13F4 is not associated with a glycolipid or a glycoprotein. It is of peptidic nature and its molecular weight is 54 kDa. We stress the value of this cell-type-specific marker in studies on ontogenesis and differentiation of all muscular structures, namely, of myocardium and striated muscles, which express 13F4 antigenicity from an early developmental stage. 相似文献
55.
E Martinez-Jaramillo R Garza-Morales MJ Loera-Arias O Saucedo-Cardenas R Montes-de-Oca-Luna LR McNally 《Biotechnic & histochemistry》2017,92(3):167-174
Fluorescent proteins are useful reporter molecules for a variety of biological systems. We present an alternative strategy for cloning reporter genes that are regulated by the nisin-controlled gene expression (NICE) system. Lactoccocus lactis was genetically engineered to express green fluorescent protein (GFP), mCherry or near-infrared fluorescent protein (iRFP). The reporter gene sequences were optimized to be expressed by L. lactis using inducible promoter pNis within the pNZ8048 vector. Expression of constructions that carry mCherry or GFP was observed by fluorescence microscopy 2 h after induction with nisin. Expression of iRFP was evaluated at 700 nm using an infrared scanner; cultures induced for 6 h showed greater iRFP expression than non-induced cultures or those expressing GFP. We demonstrated that L. lactis can express efficiently GFP, mCherry and iRFP fluorescent proteins using an inducible expression system. These strains will be useful for live cell imaging studies in vitro or for imaging studies in vivo in the case of iRFP. 相似文献
56.
T-helper 17 cell cytokines and interferon type I: partners in crime in systemic lupus erythematosus?
Zana Brkic Odilia BJ Corneth Cornelia G van Helden-Meeuwsen Radboud JEM Dolhain Naomi I Maria Sandra MJ Paulissen Nadine Davelaar Jan Piet van Hamburg Paul L van Daele Virgil A Dalm P Martin van Hagen Johanna MW Hazes Marjan A Versnel Erik Lubberts 《Arthritis research & therapy》2014,16(2):R62
Introduction
A hallmark of systemic autoimmune diseases like systemic lupus erythematosus (SLE) is the increased expression of interferon (IFN) type I inducible genes, so-called IFN type I signature. Recently, T-helper 17 subset (Th17 cells), which produces IL-17A, IL-17F, IL-21, and IL-22, has been implicated in SLE. As CCR6 enriches for Th17 cells, we used this approach to investigate whether CCR6+ memory T-helper cells producing IL-17A, IL-17F, IL-21, and/or IL-22 are increased in SLE patients and whether this increase is related to the presence of IFN type I signature.Methods
In total, 25 SLE patients and 15 healthy controls (HCs) were included. SLE patients were divided into IFN type I signature-positive (IFN+) (n = 16) and negative (IFN-) (n = 9) patients, as assessed by mRNA expression of IFN-inducible genes (IFIGs) in monocytes. Expression of IL-17A, IL-17F, IL-21, and IL-22 by CD4+CD45RO+CCR6+ T cells (CCR6+ cells) was measured with flow cytometry and compared between IFN+, IFN- patients and HCs.Results
Increased percentages of IL-17A and IL-17A/IL-17F double-producing CCR6+ cells were observed in IFN+ patients compared with IFN- patients and HCs. IL-17A and IL-17F expression within CCR6+ cells correlated significantly with IFIG expression. In addition, we found significant correlation between B-cell activating factor of the tumor necrosis family (BAFF)–a factor strongly correlating with IFN type I - and IL-21 producing CCR6+ cells.Conclusions
We show for the first time higher percentages of IL-17A and IL-17A/IL-17F double-producing CCR6+ memory T-helper cells in IFN+ SLE patients, supporting the hypothesis that IFN type I co-acts with Th17 cytokines in SLE pathogenesis. 相似文献57.
Markus Egli Simon Hafner Curdin Derungs Judith Ascher-Jenull Federica Camin Giacomo Sartori Gerald Raab Luana Bontempo Mauro Paolini Luca Ziller Tommaso Bardelli Marta Petrillo Samuel Abiven 《Biogeochemistry》2016,131(3):321-338
Only scarce information is available on how organic C is incorporated into the soil during the decay and how (micro) climate influences this process. Therefore, we investigated the effect of exposure and elevation on the organic litter decomposition and C-stabilisation in acidic soils of an Alpine environment. An experiment with artificially 13C labelled Norway spruce needles was carried out at north- and south-exposed sites between 1200 and 2400 m a.s.l. in the Italian Alps using mesocosms. After 1 year, the 13C recoveries of the bulk soil were 18.6% at the north-facing slopes and 31.5% at the south-facing slopes. A density fractionation into a light (LF; ≤1.6 g cm?3) and a heavy fraction (HF; >1.6 g cm?3) of the soil helped to identify how the applied substrate was stabilised. At the northern slope, 10.5% of the substrate was recovered in the LF and 8.1% in the HF and at the south-facing slope 22.8% in the LF and 8.1% in the HF. The overall 13C recovery was higher at the south-facing sites due to restricted water availability. Although the climate is humid in the whole area, soil moisture availability becomes more important at south-facing sites due to higher evapotranspiration. However, at sites >1700 m a.s.l, the situation changed, as the northern slope had higher recovery rates. At such altitudes, temperature effects are more dominant. This highlights the importance of locally strongly varying edaphic factors when investigating the carbon cycle. 相似文献
58.
In vitro zygotic embryo culture of wild banana significantly increased the germination compared to greenhouse grown seeds. Embryo orientation and BAP concentration significantly affected germination rate. These factors together with gelling agent, dark and light conditions and coconut water, also showed variable effects on the number of roots per plant, root length, shoot length, number of days to root emergence and number of days to shoot emergence. 相似文献
59.
60.