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101.
山羊草属异源多倍体植物基因组进化的RAPD分析 总被引:5,自引:0,他引:5
和24个随机引物对山羊草属(Aegilops L.)异源多倍体物种对其祖先二倍体物进行RAPD分析,对扩增出的313条带进行聚类分析发现,含D基因组的多倍体与二倍体祖先Ae.squarrosa(DD)在聚类图上聚为一支;除Ae.juvenalis(DDMMUU)聚到上一支外,含U基因组的多倍 与二倍体祖先Ae.umbellulata(UU)在聚类图上聚为另一支;多倍体与其他二倍体均不聚在一起,表明多倍体分别与Ae.squarrosa(DD)、Ae.umbellulata(UU)具有较近的亲缘关系,这说明多倍体开之后,D和U基因组变化较小,而其他基因组则发生了较大的变化。 相似文献
102.
Red-light-induced swelling of the protoplasts isolated from hypocotyl of etiolated mung bean(Phaseolus radiatusL.)was observed only when Ca^2 ions were present in the medium.The optimal CaCl2 concentration was 250μM,Swlling response declined when Ca^2 was supplied into the medium after red light irradiation.The Ca^2 -chelator EGTA eliminated the red-light-induced swelling and 45Ca^2 accumulation in the protoplasts.In conltrast,A23187,a Ca^2 -ionophore,could mimic the effect of red light in darkness.These results indicate that Ca^2 may play a role in light signal transduction.In addition,swelling response was prevented by TFP and CPZ(both are CaM antagonists),implying the involvement of CaM in red-light-induced and Ca^2 -dependent protoplast swelling. 相似文献
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104.
土壤微生物残留物是稳定性碳库的重要组分,然而固氮树种引入对落叶松人工林土壤团聚体微生物残留物分布的影响还不清楚.为了阐明固氮树种对不同团聚体粒级内微生物残留物分布的影响,本研究以氨基糖作为微生物残留物的生物标识物,比较了辽东日本落叶松人工纯林和落叶松与固氮树种赤杨混交林土壤团聚体氨基糖的分布特征.结果表明: 赤杨引入不影响团聚体氨基糖的分布,但显著提高了团聚体氨基糖含量.与纯林相比,混交林土壤不同团聚体各粒级总氨基糖含量增加1.3~1.7倍.其中,混交林土壤团聚体内总氨基糖增加量的66.5%~66.9%来自氨基葡萄糖,30.0%~30.6%来自氨基半乳糖,2.5%~3.2%来自胞壁酸.赤杨引入显著提高了>2000 μm和<250 μm团聚体中的氨基葡萄糖/胞壁酸值,但不影响250~2000 μm粒级团聚体中真菌和细菌残留物的相对贡献.此外,赤杨引入增加了土壤不同团聚体内的氨基糖对土壤有机碳的贡献,但不影响团聚体粒级之间的微生物贡献,说明赤杨对微生物贡献的影响存在空间均一性. 相似文献
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107.
肾上腺髓质素对大鼠肠系膜微血管和微淋巴管的作用 总被引:5,自引:0,他引:5
应用活体显微电视录象技术,观察上腺髓质素对大鼠肠系膜微血管微淋巴管的作用及其对去甲肾上腺素,内皮素作用的是结果表明,ADM直接扩张肠系膜各级微血管和向一淋巴管,拮抗NE和ET引起的微血效及微循环血流液态的异常改变。ADM的上述作用可被一氧化氮生成抑制剂N^9-nitro-L-arginine(L-NNA)显著抑制。 相似文献
108.
基于能值-生态足迹模型的东北老工业基地生态安全评价——以辽宁省为例 总被引:1,自引:1,他引:0
采用能值-生态足迹模型,对辽宁省2003—2012年生态安全状况进行时间序列的定量分析与评价,并采用灰色动力学模型预测其动态变化趋势.结果表明: 研究期内辽宁省人均能值生态承载力从3.13 hm2下降到3.07 hm2,人均能值生态足迹由13.88 hm2增加到21.96 hm2,处于生态赤字状态,且赤字增大趋势明显;生态压力指数由4.43增长到7.16,生态安全预警等级由轻警过渡到中警程度.照此发展,2013—2022年辽宁省人均能值生态承载力将由3.04 hm2下降到2.98 hm2,人均能值生态足迹将由22.72 hm2上升到35.87 hm2;生态赤字将越来越大,生态压力指数将由7.46上升到12.04,生态安全等级将由较安全变为轻度不安全状态,并呈现由中警到重警的生态安全预警等级,生态安全问题亟待解决. 相似文献
109.
HUASHENG ZHU JIANDONG WU YINGLI JIANG JING JIN WEI ZHOU YU WANG GUOMIN HAN YANG ZHAO BEIJIU CHENG 《Journal of genetics》2016,95(3):691-704
Multidrug and toxic compound extrusion (MATE) proteins are a group of secondary active transporters, which widely exist in all living organisms and play important role in the detoxication of endogenous secondary metabolites and exogenous agents. However, to date, no systematic and comprehensive study of this family is reported in maize. Here, a total of 49 MATE genes (ZmMATE) were identified and divided into seven groups by phylogenetic analysis. Conserved intro–exon structures and motif compositions were investigated in these genes. Results by gene locations indicated that these genes were unevenly distributed among all 10 chromosomes. Tandem and segmental duplications appeared to contribute to the expansion and evolution of this gene family. The Ka/ Ks ratios suggested that the ZmMATE has undergone large-scale purifying selection on the maize genome. Interspecies microsynteny analysis revealed that there were independent gene duplication events of 10 ZmMATE. In addition, most maize MATE genes exhibited different expression profiles in diverse tissues and developmental stages. Sixteen MATE genes were chosen for further quantitative real-time polymerase chain reaction analysis showed differential expression patterns in response to aluminum treatment. These results provide a useful clue for future studies on the identification of MATE genes and functional analysis of MATE proteins in maize. 相似文献
110.
Ze-you Wang Jing Xiong Shan-shan Zhang Jian-jun Wang Zhao-jian Gong Min-hui Dai 《Cellular and molecular neurobiology》2016,36(8):1303-1310
Glioblastoma multiforme (GBM) is the most common and lethal type of primary malignant brain tumor. In recent years, increasing reports suggest that discovery of microRNAs (miRNAs) might provide a novel therapeutical target for human cancers, including GBM. The expression and roles of microRNA-183 (miR-183) has been explored in several types of human cancers, including in GBM, and plays important roles in tumor initiation and progression. However, its biological functions in GBM remain largely unknown. In this study, we demonstrated that miR-183 was significantly up-regulated in astrocytoma tissues and glioblastoma cell lines. Introduction of miR-183 mimics into U251 cells could promoted, while its antisense oligos inhibited cell proliferation and invasion. Moreover, we identified neurofilament light polypeptide (NEFL) as a novel target gene of miR-183. The expression levels of NEFL are inversely correlated with that of miR-183 in human astrocytoma clinical specimens. In addition, NEFL-siRNA could significantly attenuate the inhibitory effects of knockdown miR-183 on the proliferation and invasion of U251 cells via mTOR signaling pathway. Overall, This study revealed that miR-183 promotes glioma cell proliferation by targeting NEFL, and also demonstrated that miR-183 could be a potential target for GBM treatment. 相似文献