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91.
A field experiment was conducted to determine the seasonal patterns of arbuscular mycorrhiza (AM) in a dryland winter wheat
(Triticum aestivum L.) system and to determine wheat growth and P uptake responses to inoculation with mycorrhizal fungus. Broadcast-incorporated
treatments included (1) no inoculation with mycorrhizal fungus, with and without P fertilizer, and (2) mycorrhizal fungal
inoculation at a rate of 5000 spores of Glomus intraradices (Schenck and Smith), per 30 cm in each row, with and without fertilizer P. Winter wheat was seeded within a day after treatments
were imposed, and roots were sampled at five growth stages to quantify AM. Shoot samples were also taken for determination
of dry matter, grain yield and yield components, and N and P uptake. No AM infection was evident during the fall months following
seeding, which was characterized by low soil temperature, while during the spring, the AM increased gradually. Increases in
wheat grain yields by enhanced AM were of similar magnitude to the response obtained from P fertilization. However, responses
differed at intermediate growth stages. At the tillering stage, P uptake was mainly increased by P fertilization but not by
fungal inoculation. At harvest, enhanced AM increased P uptake regardless of whether or not fertilizer P was added. The AM
symbiosis increased with rising soil temperatures in the spring, in time to enhance late-season P accumulation and grain production.
Accepted: 15 July 1998 相似文献
92.
Changtian Pan Dandan Yang Xiaolin Zhao Chen Jiao Yanqiu Yan Anthony Tumbeh Lamin‐Samu Qiaomei Wang Xiangyang Xu Zhangjun Fei Gang Lu 《Plant, cell & environment》2019,42(4):1205-1221
High temperature (HT) is becoming an increasingly serious factor in limiting crop production with global climate change. During hot seasons, owing to prevailing HT, cultivated tomatoes are prone to exhibiting stigma exsertion, which hampers pollination and causes fruit set failure. However, the underlying regulatory mechanisms of the HT‐induced stigma exsertion remain largely unknown. Here, we demonstrate that stigma exsertion induced by HT in cultivated tomato is caused by more seriously shortened stamens than pistils, which is different from the stigma exsertion observed in wild tomato species. Under the HT condition, the different responses of pectin, sugar, expansin, and cyclin cause cell wall remodelling and differentially localized cell division and selective cell enlargement, which further determine the lengths of stamens and pistils. In addition, auxin and jasmonate (JA) are implicated in regulating cell division and cell expansion in stamens and pistils, and exogenous JA instead of auxin treatment can effectively rescue tomato stigma exsertion through regulating the JA/COI1 signalling pathway. Our findings provide a better understanding of stigma exsertions under the HT condition in tomato and uncover a new function of JA in improving plant abiotic stress tolerance. 相似文献
93.
94.
Miao Yin Liang Zhang Xiao-ming Sun Liu-feng Mao Jie Pan 《Molecular biology reports》2010,37(4):2049-2054
To investigate the effect of apolipoprotein E (apoE) on cytokine expression profile of the liver of young mice, quantitative
RT-PCR (qRT-PCR) assay and cytokine antibody array for multiplex analysis of 62 cytokines have been used to analyze characteristics
of expression of cytokines in the liver of 6-week-old apoE-null (apoE−/−) mice. The levels of plasma cytokines were also analyzed. The mRNA level of IL-1β, IL-2, IL-6, ICAM-1, VCAM-1, MCP-1, NF-κB
(p65), IFN-γ and IκB-α were increased significantly in apoE−/− mice comparative to wild-type (WT) mice. IL-4, IL-10 and GM-CSF, however, were slightly decreased. Compared with WT, levels
of 21 cytokines altered twofold or more in apoE−/− mice, including 10 cytokines increased and 11 decreased. Expression patterns of IL-1β, IL-2, IL-4, IL-6, IL-10, GM-CSF, IFN-γ
and VCAM-1 showed identical trend between cytokine antibody array and qRT-PCR analysis. Moreover, levels of IL-1β, IFN-γ and
IL-6 in the plasma were elevated, while IL-4 was lightly decreased in apoE−/− mice compared to those in WT mice. These results implied that promotion of type I immune response in the liver of young apoE−/− mice due to alteration of these cytokines, and the phenotypes may be caused by the regulation of NF-κB. The inflammation
and lipid metabolism dysfunction in the liver cooperated in dysfunction of the liver in young apoE−/− mice. 相似文献
95.
96.
Seema Sharma Haiyan Zheng Yuanpeng J. Huang Asli Ertekin Yoshitomo Hamuro Paolo Rossi Roberto Tejero Thomas B. Acton Rong Xiao Mei Jiang Li Zhao Li‐Chung Ma G. V. T. Swapna James M. Aramini Gaetano T. Montelione 《Proteins》2009,76(4):882-894
Disordered or unstructured regions of proteins, while often very important biologically, can pose significant challenges for resonance assignment and three‐dimensional structure determination of the ordered regions of proteins by NMR methods. In this article, we demonstrate the application of 1H/2H exchange mass spectrometry (DXMS) for the rapid identification of disordered segments of proteins and design of protein constructs that are more suitable for structural analysis by NMR. In this benchmark study, DXMS is applied to five NMR protein targets chosen from the Northeast Structural Genomics project. These data were then used to design optimized constructs for three partially disordered proteins. Truncated proteins obtained by deletion of disordered N‐ and C‐terminal tails were evaluated using 1H‐15N HSQC and 1H‐15N heteronuclear NOE NMR experiments to assess their structural integrity. These constructs provide significantly improved NMR spectra, with minimal structural perturbations to the ordered regions of the protein structure. As a representative example, we compare the solution structures of the full length and DXMS‐based truncated construct for a 77‐residue partially disordered DUF896 family protein YnzC from Bacillus subtilis, where deletion of the disordered residues (ca. 40% of the protein) does not affect the native structure. In addition, we demonstrate that throughput of the DXMS process can be increased by analyzing mixtures of up to four proteins without reducing the sequence coverage for each protein. Our results demonstrate that DXMS can serve as a central component of a process for optimizing protein constructs for NMR structure determination. Proteins 2009. © 2009 Wiley‐Liss, Inc. 相似文献
97.
Two novel cyano‐containing oligo(phenylenevinylene) (OPV) derivatives have been designed and synthesized. Photophysical and sensing properties of the two compounds were studied. Such studies reveal the intramolecular charge transfer process between cyano groups and OPV core. The results showed that the alkyl difference of substituted OPV leads to the changes of molecular configuration and metallo‐response of two compounds. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
98.
99.
Background
Bryopsis hypnoides Lamouroux is a siphonous green alga, and its extruded protoplasm can aggregate spontaneously in seawater and develop into mature individuals. The chloroplast of B. hypnoides is the biggest organelle in the cell and shows strong autonomy. To better understand this organelle, we sequenced and analyzed the chloroplast genome of this green alga.Principal Findings
A total of 111 functional genes, including 69 potential protein-coding genes, 5 ribosomal RNA genes, and 37 tRNA genes were identified. The genome size (153,429 bp), arrangement, and inverted-repeat (IR)-lacking structure of the B. hypnoides chloroplast DNA (cpDNA) closely resembles that of Chlorella vulgaris. Furthermore, our cytogenomic investigations using pulsed-field gel electrophoresis (PFGE) and southern blotting methods showed that the B. hypnoides cpDNA had multimeric forms, including monomer, dimer, trimer, tetramer, and even higher multimers, which is similar to the higher order organization observed previously for higher plant cpDNA. The relative amounts of the four multimeric cpDNA forms were estimated to be about 1, 1/2, 1/4, and 1/8 based on molecular hybridization analysis. Phylogenetic analyses based on a concatenated alignment of chloroplast protein sequences suggested that B. hypnoides is sister to all Chlorophyceae and this placement received moderate support.Conclusion
All of the results suggest that the autonomy of the chloroplasts of B. hypnoides has little to do with the size and gene content of the cpDNA, and the IR-lacking structure of the chloroplasts indirectly demonstrated that the multimeric molecules might result from the random cleavage and fusion of replication intermediates instead of recombinational events. 相似文献100.
Rong Pan Lixiang Cao Haiwei Huang Renduo Zhang Yu Mo 《Applied microbiology and biotechnology》2010,88(4):997-1005
In this study, dried and humid fruiting bodies of Tremella fuciformis and Auricularia polytricha were examined as cost-effective biosorbents in treatment of heavy metals (Cd2+, Cu2+, Pb2+, and Zn2+) in aqueous solution. The humid T. fuciformis showed the highest capacity to adsorb the four metals in the multi-metal solutions. The Pb2+ adsorption rates were 85.5%, 97.8%, 84.8%, and 91.0% by dried T. fuciformis, humid T. fuciformis, dried A. polytricha, and humid A. polytricha, respectively. The adsorption amount of Pb2+ by dried and humid T. fuciformis in Cd2+ + Pb2+, Cu2+ + Pb2+, Pb2+ + Zn2+, Cd2+ + Cu2+ + Pb2+, and Cd2+ + Zn2+ + Pb2+ solutions were not lower than that in Pb2+ solutions. The results suggested that in humid T. fuciformis, Cd2+, Cu2+, and Zn2+ promoted the Pb2+ adsorption by the biomass. In the multi-metal solutions of Cd2+ + Cu2+ + Pb2+ + Zn2+, the adsorption amount and rates of the metals by all the test biosorbents were in the order of Pb2+ > Cu2+ > Zn2+ > Cd2+. Compared with the pseudo first-order model, the pseudo second-order model described the adsorption kinetics much better,
indicating a two-step biosorption process. The present study confirmed that fruiting bodies of the jelly fungi should be useful
for the treatment of wastewater containing Cd2+, Cu2+, Pb2+, and Zn2+. 相似文献