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51.
WeiJiang Luan Ao Shen ZhiPing Jin SuSheng Song ZhengLong Li AiHua Sha 《中国科学:生命科学英文版》2013,56(12):1113-1123
The class III homeodomain-leucine zipper (HD-Zip III) gene family plays important roles in plant growth and development, including regulation of apical embryo patterning, embryonic shoot meristem formation, leaf polarity, vascular development, and meristem function, with a particularly crucial function in leaf development. Although HD-Zip III members are highly conserved in land plants, previous studies, such as genetic analyses based on multiple mutants in Arabidopsis and other plants, suggest that various HD-Zip III family genes have evolved with distinct functions and pleiotropic effects on plant growth and development. In this study, we analyzed a HD-Zip III member, OsHox33, and demonstrated that it plays an important role in age-dependent leaf senescence in rice. We constructed two specific RNAi vectors derived from the 5′-end region and 3′-UTR of OsHox33 to knockdown its expression. Transgenic plants harboring either RNAi construct displayed similar phenotypes of precocious leaf senescence symptoms, suggesting that knockdown of OsHox33 accelerates leaf senescence in rice. pOsHox33::GUS fusion expression and RT-PCR revealed that OsHox33 is highly expressed in young organs, especially in young meristems such as shoot apical meristems, intercalary meristems, and young callus. In addition, real-time PCR indicated that OsHox33 was more highly expressed in young leaves than in old leaves. To further investigate OsHox33 function, we analyzed chloroplast ultrastructure in different-aged leaves of RNAi plants, and found that OsHox33 knockdown accelerated chloroplast degradation, which is consistent with RNAi phenotypes. Finally, real-time PCR studies showed that OsHox33 can regulate the expression of GS1 and GS2, two senescence-associated genes. Taken together, the work presented here provides new insights into the function of HD-Zip III members in plants. 相似文献
52.
A validated HPLC-DAD-ESI-MSn method for the analysis of non-anthocyanin flavonoids was applied to nine different tissues of twelve lotus genotypes of Nelumbo nucifera and N. lutea, together with an optimized anthocyanin extraction and separation protocol for lotus petals. A total of five anthocyanins and twenty non-anthocyanin flavonoids was identified and quantified. Flavonoid contents and compositions varied with cultivar and tissue and were used as a basis to divide tissues into three groups characterized by kaempferol and quercetin derivatives. Influences on flower petal coloration were investigated by principal components analyses. High contents of kaempferol glycosides were detected in the petals of N. nucifera while high quercetin glycoside concentrations occurred in N. lutea. Based on these results, biosynthetic pathways leading to specific compounds in lotus tissues are deduced through metabolomic analysis of different genotypes and tissues and correlations among flavonoid compounds. 相似文献
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Mithun Das Jin Sha Bertha Hidalgo Stella Aslibekyan Anh N. Do Degui Zhi Dianjianyi Sun Tao Zhang Shengxu Li Wei Chen Sathanur R. Srinivasan Hemant K. Tiwari Devin Absher Jose M. Ordovas Gerald S. Berenson Donna K. Arnett Marguerite R. Irvin 《PloS one》2016,11(1)
In this study, we conducted an epigenome-wide association study of metabolic syndrome (MetS) among 846 participants of European descent in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN). DNA was isolated from CD4+ T cells and methylation at ~470,000 cytosine-phosphate-guanine dinucleotide (CpG) pairs was assayed using the Illumina Infinium HumanMethylation450 BeadChip. We modeled the percentage methylation at individual CpGs as a function of MetS using linear mixed models. A Bonferroni-corrected P-value of 1.1 x 10−7 was considered significant. Methylation at two CpG sites in CPT1A on chromosome 11 was significantly associated with MetS (P for cg00574958 = 2.6x10-14 and P for cg17058475 = 1.2x10-9). Significant associations were replicated in both European and African ancestry participants of the Bogalusa Heart Study. Our findings suggest that methylation in CPT1A is a promising epigenetic marker for MetS risk which could become useful as a treatment target in the future. 相似文献
55.
Jinghui Lei Sha Peng Sonia B. Samuel Suli Zhang Ye Wu Pengli Wang Ya-Feng Li Huirong Liu 《Analytical biochemistry》2016
Human umbilical vein endothelial cells (HUVECS) are used as an irreplaceable tool for the study of vascular diseases. However, the technicians who isolate HUVECs are largely exposed to potential infectious threats. Here we report the development of a specialized instrument to protect researchers from known or unknown infectious agents when they operate on human umbilical cords. This instrument can be assembled by common laboratory supplies and adapted to accommodate umbilical cords of different lengths. When the cord is enclosed within the instrument, the risk of sample contamination and operator infection is greatly reduced. Using our instrument, endothelial cells were successfully isolated from human umbilical veins without contamination. The cells were verified by their cobblestone-like morphology and by immunofluorescence staining (Factor VIII and CD31 positivity and α-SMA negativity). Our instrument simplifies and optimizes the cell extraction process, and most importantly elevates the biosafety to a higher level during the isolation of human umbilical vein endothelial cells. 相似文献
56.
Genomic constitution and taxonomy of the Chinese hexaploids Elymus cylindricus and E. breviaristatus (Poaceae: Triticeae) 下载免费PDF全文
Cai‐Rong Yang Bernard‐R. Baum Wei‐Huan Chen Hai‐Qin Zhang Xiao‐Yan Liu Xing Fan Li‐Na Sha Hou‐Yang Kang Yi Wang Yong‐Hong Zhou 《Botanical journal of the Linnean Society. Linnean Society of London》2016,182(3):650-657
Elymus cylindricus (2n = 6x = 42) and E. breviaristatus (2n = 6x = 42) are distributed in grasslands and deserts of northern and north‐western China. Their genomic constitution and taxonomic status are unclear. Elymus cylindricus was crossed with E. wawawaiensis J.R.Carlson & Barkworth ( StH ), Roegneria grandis Keng ( StY ) and Campeiostachys dahurica (Turcz. ex Griseb.) B.R.Baum, J.L. Y ang & C. Y en var. dahurica ( StYH ). Meiotic pairing in the hybrids E. cylindricus × E. wawawaiensis ( StH ), E. cylindricus × R. grandis ( StY ) and E. cylindricus × C. dahurica var. dahurica ( StYH ) showed on average 10.00, 11.30 and 20.92 bivalents per cell, respectively. Elymus breviaristatus was crossed with C. dahurica var. dahurica ( StYH ) and E. cylindricus. Chromosome pairing in the hybrids of E. breviaristatus × C. dahurica var. dahurica and E. breviaristatus × E. cylindricus showed on average 19.60 and 19.27 bivalents, respectively. Genomic in situ hybridization (GI SH ) revealed the presence of St , Y and H genomes in E. cylindricus and E. breviaristatus. An intergenomic rearrangement was observed in E. cylindricus using GI SH . Meiotic pairing data and GI SH indicated that both E. cylindricus and E. breviaristatus are allohexaploids containing the StYH genomes. Elymus cylindricus and E. breviaristatus should be treated as Campeiostachys dahurica var. cylindrica and Campeiostachys breviaristata, respectively. 相似文献
57.
Sugars act as vital signaling molecules that regulate plant growth, development and stress responses. However, the effects of sugars on stomatal movement have been unclear. In our study, we explored the effects of monosaccharides such as glucose and mannose on stomatal aperture. Here, we demonstrate that glucose and mannose trigger stomatal closure in a dose‐ and time‐dependent manner in epidermal peels of broad bean (Vicia faba). Pharmacological studies revealed that glucose‐ and mannose‐induced stomatal closure was almost completely inhibited by two reactive oxygen species (ROS) scavengers, catalase (CAT) and reduced glutathione (GSH), was significantly abolished by an NADPH oxidase inhibitor, diphenylene iodonium chloride (DPI), whereas they were hardly affected by a peroxidase inhibitor, salicylhydroxamic acid (SHAM). Furthermore, glucose‐ and mannose‐induced stomatal closure was strongly inhibited by a Ca2+ channel blocker, LaCl3, a Ca2+ chelator, ethyleneglycol‐bis(beta‐aminoethylether)‐N,N'‐tetraacetic acid (EGTA) and two water channel blockers, HgCl2 and dimethyl sulfoxide (DMSO); whereas the inhibitory effects of the water channel blockers were essentially abolished by the reversing agent β‐mercaptoethanol (β‐ME). These results suggest that ROS production mainly via NADPH oxidases, Ca2+ and water channels are involved in glucose‐ and mannose‐induced stomatal closure. 相似文献
58.
Weiliang Qi Yao Tang Wei Zhu Daiyan Li Chengdou Diao Lili Xu Jian Zeng Yi Wang Xing Fan Lina Sha Haiqin Zhang Youliang Zheng Yonghong Zhou Houyang Kang 《Planta》2016,244(2):405-416
Main conclusion
A new wheat-rye 1BL?1RS translocation line, with the characteristics of superior stripe rust resistance and high thousand-kernel weight and grain number per spike, was developed and identified from progenies of wheat-rye- Psathyrostachys huashanica trigeneric hybrids.Abstract
The wheat-rye 1BL?1RS translocation line from Petkus rye has contributed substantially to the world wheat production. However, due to extensive growing of cultivars with disease resistance genes from short arm of rye chromosome 1R and coevolution of pathogen virulence and host resistance, these cultivars successively lost resistance to pathogens. In this study, a new wheat-rye line K13-868, derived from the progenies of wheat-rye-Psathyrostachys huashanica trigeneric hybrids, was identified and analyzed using fluorescence in situ hybridization (FISH), genomic in situ hybridization (GISH), acid polyacrylamide gel electrophoresis (A-PAGE), and molecular markers. Cytological studies indicated that the mean chromosome configuration of K13-868 at meiosis was 2n = 42 = 0.14 I + 18.78 II (ring) + 2.15 II (rod). Sequential FISH and GISH results demonstrated that K13-868 was a compensating wheat-rye 1BL?1RS Robertsonian translocation line. Acid PAGE analysis revealed that clear specific bands of rye 1RS were expressed in K13-868. Simple sequence repeat (SSR) and rye 1RS-specific markers ω-sec-p1/ω-sec-p2 and O-SEC5′-A/O-SEC3′-R suggested that the 1BS arm of wheat had been substituted by the 1RS arm of rye. At the seedling and adult growth stage, compared with its recurrent wheat parent SM51 and six other wheat cultivars containing the 1RS arm in southwestern China, K13-868 showed high levels of resistance to stripe rust (Puccinia striiformis f. sp. tritici, Pst) pathogens prevalent in China, which are virulent to Yr10 and Yr24/Yr26. In addition, K13-868 expresses higher thousand-kernel weight and more grain number per spike than these controls in two growing seasons, suggesting that this line may carry yield-related genes of rye. This translocation line, with significant characteristics of resistance to stripe rust and high thousand-kernel weight and grain number per spike, could be utilized as a valuable germplasm for wheat improvement.59.
Anaerobic methane oxidation coupled to nitrite reduction can be a potential methane sink in coastal environments 总被引:1,自引:0,他引:1
60.