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941.
A proteomic analysis was conducted to map the events during the initial stages of the interaction between the fungal pathogen Fusarium graminearum and the susceptible barley cultivar Scarlett. Quantification of fungal DNA demonstrated a sharp increase in fungal biomass in barley spikelets at 3 days after inoculation. This coincided with the appearance of discrete F. graminearum-induced proteolytic fragments of β-amylase. Based on these results, analysis of grain proteome changes prior to extensive proteolysis enabled identification of barley proteins responding early to infection by the fungus. In total, the intensity of 51 protein spots was significantly changed in F. graminearum-infected spikelets and all but one were identified. These included pathogenesis-related proteins, proteins involved in energy metabolism, secondary metabolism and protein synthesis. A single fungal protein of unknown function was identified. Quantitative real-time RT-PCR analysis of selected genes showed a correlation between high gene expression and detection of the corresponding proteins. Fungal genes encoding alkaline protease and endothiapepsin were expressed during 1-3 days after inoculation, making them candidates for generation of the observed β-amylase fragments. These fragments have potential to be developed as proteome-level markers for fungal infection that are also informative about grain protein quality.  相似文献   
942.
To study the soybean plasma membrane proteome under osmotic stress, two methods were used: a gel‐based and a LC MS/MS‐based proteomics method. Two‐day‐old seedlings were subjected to 10% PEG for 2 days. Plasma membranes were purified from seedlings using a two‐phase partitioning method and their purity was verified by measuring ATPase activity. Using the gel‐based proteomics, four and eight protein spots were identified as up‐ and downregulated, respectively, whereas in the nanoLC MS/MS approach, 11 and 75 proteins were identified as up‐ and downregulated, respectively, under PEG treatment. Out of osmotic stress responsive proteins, most of the transporter proteins and all proteins with high number of transmembrane helices as well as low‐abundance proteins could be identified by the LC MS/MS‐based method. Three homologues of plasma membrane H+‐ATPase, which are transporter proteins involved in ion efflux, were upregulated under osmotic stress. Gene expression of this protein was increased after 12 h of stress exposure. Among the identified proteins, seven proteins were mutual in two proteomics techniques, in which calnexin was the highly upregulated protein. Accumulation of calnexin in plasma membrane was confirmed by immunoblot analysis. These results suggest that under hyperosmotic conditions, calnexin accumulates in the plasma membrane and ion efflux accelerates by upregulation of plasma membrane H+‐ATPase protein.  相似文献   
943.
The comprehension of metal homeostasis in plants requires the identification of molecular markers linked to stress tolerance. Proteomic changes in leaves and cambial zone of Populus tremula×P. alba (717‐1B4 genotype) were analyzed after 61 days of exposure to cadmium (Cd) 360 mg/kg soil dry weight in pot‐soil cultures. The treatment led to an acute Cd stress with a reduction of growth and photosynthesis. Cd stress induced changes in the display of 120 spots for leaf tissue and 153 spots for the cambial zone. It involved a reduced photosynthesis, resulting in a profound reorganisation of carbon and carbohydrate metabolisms in both tissues. Cambial cells underwent stress from the Cd actually present inside the tissue but also a deprivation of photosynthates caused by leaf stress. An important tissue specificity of the response was observed, according to the differences in cell structures and functions.  相似文献   
944.
Three years after a river restoration scheme in the Syr Valley (Luxembourg) we investigated habitat development and habitat use of Galloway cattle deployed in a low-intensity grazing system on a permanent floodplain pasture. Habitats were delimited with a mobile GPS/GIS mapping system and their spatial development was assessed over three consecutive years. During these three years, the patches of the six habitats decreased to 40% of mean initial size, and a rapid net area expansion of wetland habitats (large sedge swamps: +100%, marsh and tall forb grasslands: +43%) was observed. The behavioural patterns and grazing preferences of the cattle were observed directly during the vegetation period in June, August and November. These observations were complemented by a transect analysis of cattle impact indicators in June and November. The cattle grazed the different habitats very selectively, as they preferred the mesophilic, and ruderal grasslands 1.6, and 5.6 times more than expected respectively. During the growing season, the grazing niche breadth declined (3.92 in June to 2.68 in November), and less preferred forage habitats like large sedge swamps were grazed primarily in the autumn. We used bite and step rates to investigate grazing intensity by habitat type. During summer, grazing intensity correlated with forage quality in the different habitat patches, whereas in autumn it was obviously influenced by the effort required to access the desired forage plants in a given habitat. The impact indicators revealed a matter transfer from riparian areas to the valley edge. Here, we give a first insight into habitat development and habitat use of Galloway cattle in a recently restored floodplain area and derive recommendations for the adaptive management of future projects.  相似文献   
945.
Documenting the basic patterns of biodiversity and accurately determining the priority areas are the first steps for conservation studies. Threatened species and IUCN (International Union for Conservation of Nature) Red Lists are among the widely used tools to identify protected areas. Turkey is one of the most important biodiversity centres in the world. The plant diversity of Turkey with over 30% endemic species of approximately 12000 natural vascular plant taxa is well documented through use of a Grid System. However, Turkey has suffered heavy anthropogenic effects having been a settlement for many civilisations throughout the history of humankind. Therefore, Turkey needs a quantitative evaluation of the importance of different grid squares for conserving plant diversity. This paper offers a quantitative approach for aiding the identification of priority areas for biodiversity conservation by analysing the threatened plants in each grid square in terms of endemism, risk categories and distribution characteristics. The grid squares (nearly 220 x 170 km2) were then classified within four different groups in terms of their conservation importance. This national-level information can be used for further research and decision-making processes for conservation planning.  相似文献   
946.
Cell suspension cultures of Lavandula vera (Lamiaceae), Nicotiana tabacum (Solanaceae), and Helianthus annuus (Asteraceae) were cultivated in three different ways: in shake flasks both as free suspensions and in two‐phase systems (in the presence of Amberlite XAD‐4 resin as a second phase), as well as in 3‐L stirred tank reactor, and their volatile metabolic profiles were studied using GC‐MS. A number of compounds, some of them having allelochemical and biological activities, were identified in all the three cell suspension cultures under study. Also the presence of some compounds, unusual for the intact plants, was observed. It was found that the cultivation mode strongly influences the production and the transport (secretion into the culture medium) of the low‐molecular‐mass volatile metabolites. Principal component analyses of 12 common hydrocarbons showed discrimination between the different cultivation modes (shake flasks and two‐phase systems cultivation) by first principal component (PC1) and second principal component (PC2).  相似文献   
947.
蛋白亚硝基化研究进展及其在植物抗病中的作用   总被引:1,自引:1,他引:0  
蛋白亚硝基化(S-nitrosylation)是一种在一氧化氮作用下与蛋白半胱氨酸巯基共价结合,使巯基-SH转化为-SNO的反应。作为一种氧化还原依赖的翻译后调控形式,蛋白亚硝基化对多种蛋白的功能具有调节作用,越来越多的证据表明蛋白亚硝基化在植物抗病中发挥重要的作用。简要介绍了蛋白巯基亚硝基化的特点、检测方法、功能研究以及在植物抗病调节方面的最新进展。  相似文献   
948.
Artificial insemination (AI) with liquid-stored spermatozoa and sperm cryopreservation using directional freezing (DF) have been successful in the beluga. This study built on this foundation to develop a deep intra-uterine AI technique with frozen-thawed semen in beluga. Forty-two ejaculates from one male were cryopreserved using DF technology and subsequently used for 10 insemination attempts with seven females. Percentage pre- and post-thaw progressive motility and viability were (mean ± SD) 73.0 ± 12.2, 38.4 ± 8.8, 88.0 ± 0.1, and 59.3 ± 15.7%, respectively. A series of GnRH injections (3 x 250 μg, IV, 1.5 to 2 h apart) were used to induce ovulation, once a growing follicle >2.5 cm in diameter was visualized via trans-abdominal ultrasonography. Artificial insemination was performed at 30.1 ± 3.8 h post-initial GnRH injection with semen deposited in the uterine horn, 92.6 ± 16.2 cm beyond the genital opening using a flexible endoscope. The external cervical os (cEOS) was located beyond a series of 5 to 10 vaginal rings, 44.8 ± 9.3 cm from the external genital opening. The internal bifurcation of the uterus was 27 ± 6.8 cm beyond the cEOS. Ovulation occurred at 8.5 ± 7.6 h post-AI. Two of 10 inseminations (20%) resulted in pregnancy. The first pregnancy resulted in twins; both calves were born 442 d after AI, with one surviving. The second pregnancy is ongoing. These findings represent the first successful application of AI using frozen-thawed semen in beluga, and are important examples of how assisted reproductive technologies can provide tools for the global management of threatened species.  相似文献   
949.
Fad104 (factor for adipocyte differentiation 104) is a novel gene expressed temporarily in the early stages of adipocyte differentiation. Previously, we showed that fad104 promotes adipocyte differentiation in mouse 3T3-L1 cells and mouse embryonic fibroblasts (MEFs). Furthermore, we reported that implanted wild-type MEFs could develop into adipocytes, whereas fad104-deficient MEFs could not. Interestingly, bone-like tissues were only observed in the implants derived from fad104-deficient MEFs. This result implies that fad104 is involved in osteoblast differentiation. However, the functions of fad104 during osteogenesis are unknown. In this paper, we show that fad104 negatively regulates osteoblast differentiation. During the differentiation process, the level of fad104 expression decreased. Deletion of fad104 facilitated osteoblast differentiation in MEFs, and elevated the level of runx2, a master regulator of osteoblast differentiation. Disruption of fad104 suppressed BMP-2-mediated adipocyte differentiation in MEFs. In conclusion, we demonstrate that fad104 reciprocally regulates differentiation of adipocytes and osteoblast; functions as a positive regulator in adipocyte differentiation and as a negative regulator in osteoblast differentiation.  相似文献   
950.
Plant Ca2+ signals are involved in a sizable array of intracellular signaling pathways after pest invasion. Upon herbivore feeding there is a dramatic Ca2+ influx, followed by the activation of Ca2+-dependent signal transduction pathways that include interacting downstream networks of kinases for defense responses. Notably, Ca2+-binding sensory proteins such as Ca2+-dependent protein kinases (CPKs) have recently been documented to mediate the signaling following Ca2+ influx after herbivory, in phytohormone-independent manners. Here, we review the sequence of signal transductions triggered by herbivory-evoked Ca2+ signaling leading to CPK actions for defense responses, and discuss in a comparative way the involvement of CPKs in the signal transduction of a variety of other biotic and abiotic stresses.  相似文献   
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