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961.
Caragana korshinskii seedlings maintain positive photosynthesis during short-term,severe drought stress 总被引:1,自引:0,他引:1
Seedling performance may determine plant distribution, especially in water-limited environments. Plants of Caragana korshinskii commonly grow in arid and semiarid areas in northwestern China, and endure water shortage in various ways, but little is
known about their performance when water shortage occurs at early growth stages. The water relations, photosynthetic activity,
chlorophyll (Chl) content and proline accumulation were determined in 1-year-old seedlings growing in a 1:1 mixture of Loess
soil and Perlite and subjected to (1) a water deficit for 20 days and (2) kept adequately watered throughout. The water deficit induced low (−6.1 MPa) predawn leaf water potentials (LWP), but did
not induce any leaf abscission. Stomatal conductance (g
s), leaf transpiration rate (E), and net photosynthetic rate (P
N) decreased immediately following the imposition of the water deficit, while the maximal photochemical efficiency of photosystem
II (PSII) (Fv/Fm) and the effective quantum yield of PSII (ΦPSII) decreased 15 days later. An early and rapid decrease in g
s, reduced E, increased Chl (a+b) loss, increased the apparent rate of photochemical transport of electrons through PSII (ETR)/P
N, as well as a gradual increase in non-photochemical quenching of fluorescence (NPQ) and proline may have contributed to preventing
ΦPSII from photodamage. C. korshinskii seedlings used a stress-tolerance strategy, with leaf maintenance providing a clear selective advantage, considering the
occasional rainfall events during the growing season. 相似文献
962.
Li Wen-Ru Ma Yong-Kai Shi Qing-Shan Xie Xiao-Bao Sun Ting-Li Peng Hong Huang Xiao-Mo 《Applied microbiology and biotechnology》2018,102(17):7555-7564
Applied Microbiology and Biotechnology - Garlic oil can disrupt the quorum sensing (QS) pathways of the opportunistic pathogen Pseudomonas aeruginosa; however, the underlying mechanisms for this... 相似文献
963.
964.
Meng F Han Y Teng W Li Y Li W 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(8):1459-1465
Soybean aphid (Aphis glycines Matsumura) results in severe yield loss of soybean in many soybean-growing countries of the world. A few loci have been previously
identified to be associated with the aphid resistance in soybean. However, none of them was via isoflavone-mediated antibiosis
process. The aim of the present study was to conduct genetic analysis of aphid resistance and to identify quantitative trait
loci (QTL) underlying aphid resistance in a Chinese soybean cultivar with high isoflavone content. One hundred and thirty
F5:6 derived recombinant inbred lines from the ‘Zhongdou 27’ × ‘Jiunong 20’ cross were used. Two QTL were directly associated
with resistance to aphid as measured by aphid damage index. qRa_1, close to Satt470 on soybean linkage group (LG) A2 (chromosome
8), was consistently detected for 3- and 4-week ratings and explained a large portion of phenotypic variations ranging from
25 to 35%. qRa_2, close to Satt144 of LG F (chromosome 13), was detected for 3- and 4-week ratings and could explain 7 and
11% of the phenotypic variation, respectively. These two QTL were highly associated with high isoflavone content and both
positive alleles were derived from ‘Zhongdou 27’, a cultivar with higher isoflavone content. The results revealed that higher
individual or total isoflavones contents in soybean lines could protect soybean against aphid attack. These two QTL detected
jointly provide potential for marker-assisted selection to improve the resistance of soybean cultivars to aphid along with
the increase of isoflavone content. 相似文献
965.
Vibrio cholerae can be differentiated into epidemic and non-epidemic strains by sorbitol fermentation speed, but little research has been done on its mechanisms. In this study, we investigated differential protein expression of the two strains in response to sorbitol metabolism. V. cholerae strains were cultured in media with and without sorbitol, respectively. Proteins were separated by 2-DE, and those that showed different expression in the two media were identified by MALDI-TOF MS. Fifteen proteins in epidemic strains and 11 proteins in non-epidemic strains showed a different expression in sorbitol medium. Among them, 4 proteins were common to epidemic and non-epidemic strains. Gene sequence analysis showed that some mutations occurred in these proteins between the two strains. Potential functions of these proteins included sugar uptake, amino acid uptake, electron transport, sulfate and thiosulfate transport. 相似文献
966.
Chemokine-like factor 1 (CKLF1) is a cytokine with chemotactic effects on leukocytes and a functional ligand of CCR4. This cytokine is widely expressed and the level of expression is reported to be upregulated in asthma and rheumatoid arthritis (RA), disease conditions in which T lymphocytes are over-activated. In order to determine the expression profile of CKLF1 in activated T lymphocytes, we first employed a PCR-based method on human blood fractions cDNA panels and found that CKLF1 was upregulated in activated CD4+ and CD8+ cells, with no obvious changes in CD19+ cells. We further performed kinetic analyses of CKLF1 expression in phytohemagglutinin (PHA)-stimulated human peripheral blood lymphocytes (PBL) at both the mRNA and protein levels. In resting PBL, the constitutive expression of CKLF1 was low at mRNA level and barely detectable at the protein level; however, both were remarkably upregulated by PHA, appearing at 8h after PHA-stimulation and persisting up to 72h. These results suggest that CKLF1 may be involved in T lymphocyte activation and further study of CKLF1 function will prove valuable. 相似文献
967.
968.
969.
Li Xiaoyu Liang Qiao-Xia Lin Jin-Ran Peng Jinying Yang Jian-Hua Yi Chengqi Yu Yang Zhang Qiangfeng Cliff Zhou Ke-Ren 《中国科学:生命科学英文版》2020,63(4):501-515
RNA can interact with RNA-binding proteins(RBPs), mRNA, or other non-coding RNAs(ncRNAs) to form complex regulatory networks. High-throughput CLIP-seq, degradome-seq, and RNA-RNA interactome sequencing methods represent powerful approaches to identify biologically relevant ncRNA-target and protein-ncRNA interactions. However, assigning ncRNAs to their regulatory target genes or interacting RNA-binding proteins(RBPs) remains technically challenging. Chemical modifications to mRNA also play important roles in regulating gene expression. Investigation of the functional roles of these modifications relies highly on the detection methods used. RNA structure is also critical at nearly every step of the RNA life cycle. In this review, we summarize recent advances and limitations in CLIP technologies and discuss the computational challenges of and bioinformatics tools used for decoding the functions and regulatory networks of ncRNAs. We also summarize methods used to detect RNA modifications and to probe RNA structure. 相似文献
970.
A huge amount of information is stored in genomic DNA and this stored information resides inside the nucleus with the aid of chromosomal condensation factors. It has been reported that the repeat nucleosome core particle (NCP) consists of 147-bp of DNA and two copies of H2A, H2B, H3 and H4. Regulation of chromosomal structure is important to many processes inside the cell. In vivo, a group of histone chaperones facilitate and regulate nucleosome assembly. How NCPs are constructed with the aid of histone chaperones remains unclear. In this study, the histone chaperone-mediated nucleosome assembly process was investigated using single-molecule tethered particle motion (TPM) experiments. It was found that Asf1 is able to exert more influence than Nap1 and poly glutamate acid (PGA) on the nucleosome formation process, which highlights Asf1’s specific role in tetrasome formation. Thermodynamic parameters supported a model whereby energetically favored nucleosomal complexes compete with non-nucleosomal complexes. In addition, our kinetic findings propose the model that histone chaperones mediate nucleosome assembly along a path that leads to enthalpy-favored products with free histones as reaction substrates. 相似文献