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1.
Weixiao Lei Zefu Wang Man Cao Hui Zhu Min Wang Yi Zou Yunchun Han Dandan Wang Zeyu Zheng Ying Li Bingbing Liu Dafu Ru 《DNA research》2022,29(3)
Sophora japonica is a medium-size deciduous tree belonging to Leguminosae family and famous for its high ecological, economic and medicinal value. Here, we reveal a draft genome of S. japonica, which was ∼511.49 Mb long (contig N50 size of 17.34 Mb) based on Illumina, Nanopore and Hi-C data. We reliably assembled 110 contigs into 14 chromosomes, representing 91.62% of the total genome, with an improved N50 size of 31.32 Mb based on Hi-C data. Further investigation identified 271.76 Mb (53.13%) of repetitive sequences and 31,000 protein-coding genes, of which 30,721 (99.1%) were functionally annotated. Phylogenetic analysis indicates that S. japonica separated from Arabidopsis thaliana and Glycine max ∼107.53 and 61.24 million years ago, respectively. We detected evidence of species-specific and common-legume whole-genome duplication events in S. japonica. We further found that multiple TF families (e.g. BBX and PAL) have expanded in S. japonica, which might have led to its enhanced tolerance to abiotic stress. In addition, S. japonica harbours more genes involved in the lignin and cellulose biosynthesis pathways than the other two species. Finally, population genomic analyses revealed no obvious differentiation among geographical groups and the effective population size continuously declined since 2 Ma. Our genomic data provide a powerful comparative framework to study the adaptation, evolution and active ingredients biosynthesis in S. japonica. More importantly, our high-quality S. japonica genome is important for elucidating the biosynthesis of its main bioactive components, and improving its production and/or processing. 相似文献
2.
叶绿体基因组编码许多参与光合作用和其他代谢过程的关键蛋白质,在叶绿体中合成的代谢物对于植物正常的生长发育至关重要。根对紫外线-B辐射敏感[Root-UVB (ultraviolet radiation B)-sensitive, RUS]蛋白属于叶绿体蛋白,由高度保守的DUF647结构域组成,在参与植物形态发生、物质运输和能量代谢等多种生命活动的调控中发挥作用。本文就近年来关于RUS家族在植物的胚胎发育、光形态建成、维生素B6稳态、生长素转运和花药发育等生长发育过程中的相关研究进行回顾和总结,为深入研究其在植物生长发育中的分子调控机制提供了参考。 相似文献
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4.
Katherine M. Littlefield Rene O. Watson Jennifer M. Schneider Charles P. Neff Eiko Yamada Min Zhang Thomas B. Campbell Michael T. Falta Sarah E. Jolley Andrew P. Fontenot Brent E. Palmer 《PLoS pathogens》2022,18(5)
As of January 2022, at least 60 million individuals are estimated to develop post-acute sequelae of SARS-CoV-2 (PASC) after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While elevated levels of SARS-CoV-2-specific T cells have been observed in non-specific PASC, little is known about their impact on pulmonary function which is compromised in the majority of these individuals. This study compares frequencies of SARS-CoV-2-specific T cells and inflammatory markers with lung function in participants with pulmonary PASC and resolved COVID-19 (RC). Compared to RC, participants with respiratory PASC had between 6- and 105-fold higher frequencies of IFN-γ- and TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells in peripheral blood, and elevated levels of plasma CRP and IL-6. Importantly, in PASC participants the frequency of TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells, which exhibited the highest levels of Ki67 indicating they were activity dividing, correlated positively with plasma IL-6 and negatively with measures of lung function, including forced expiratory volume in one second (FEV1), while increased frequencies of IFN-γ-producing SARS-CoV-2-specific T cells associated with prolonged dyspnea. Statistical analyses stratified by age, number of comorbidities and hospitalization status demonstrated that none of these factors affect differences in the frequency of SARS-CoV-2 T cells and plasma IL-6 levels measured between PASC and RC cohorts. Taken together, these findings demonstrate elevated frequencies of SARS-CoV-2-specific T cells in individuals with pulmonary PASC are associated with increased systemic inflammation and decreased lung function, suggesting that SARS-CoV-2-specific T cells contribute to lingering pulmonary symptoms. These findings also provide mechanistic insight on the pathophysiology of PASC that can inform development of potential treatments to reduce symptom burden. 相似文献
5.
土壤不同水分条件对长春花(Catharanthus roseus)生活史型的影响 总被引:4,自引:4,他引:0
为了研究土壤中不同水分条件对长春花生活史型形成及生理代谢的影响,设置对照、轻度干旱、中度干旱和重度干旱等土壤水分梯度,对长春花(Catharanthus roseus(L.)G.Don)幼苗进行处理。对长春花形态指标进行聚类分析发现选择的20个聚类实体被分为2组,第1组为对照(CK)和轻度干旱(LD)处理的植株,第2组为中度干旱(MD)和重度干旱(HD)处理的植株。运用主成分分析(Principal component analysis,PCA)方法对不同土壤水分条件下长春花营养生长(Vegetative growth,V)、有性生殖(Sexual reproduction,S)和无性繁殖(Clone reproduction,C)等3类15种性状进行统计。结果显示,长春花在对照条件下生活史型为V0.39S0.54C0.07,轻度干旱为V0.36S0.50C0.14,中度干旱为V0.53S0.27C0.20,重度干旱为V0.45S0.09C0.46,干旱程度加强显著提高了无性繁殖的比重,降低了有性生殖的比例。同时,对长春花中文朵灵、长春质碱和脱水长春碱等生物碱的含量进行了动态测定,发现重度干旱下的文朵灵、长春质碱和脱水长春碱的含量在16d时分别是对照水平的1.5倍、2.3倍和3.1倍,表明干旱胁迫诱导生物碱积累,为长春花高效栽培提供了理论依据。 相似文献
6.
以模式植物拟南芥为材料,通过PCR和RT-PCR在DNA和RNA水平上筛选鉴定了DTX31基因对应的T-DNA插入突变体,对其表型变化进行了观察.通过半定量RT-PCR分析检测了DTX31基因在拟南芥不同器官及环境胁迫响应中的表达情况,结果发现:DTX31基因在根中表达最高,而在茎、叶、叶柄、花中的表达则较弱;盐和赤霉素使DTX31基因的表达迅速升高,盐胁迫2 h后的表达量达到最高峰,GA处理1 h时就达到最高峰,热激使DTX31基因的表达变化不明显.因此,推测该基因可能是盐和GA信号传导通路中的一个重要调控因子. 相似文献
7.
Enhancement of hyperthermia-induced apoptosis by local anesthetics on human histiocytic lymphoma U937 cells 总被引:2,自引:0,他引:2
Arai Y Kondo T Tanabe K Zhao QL Li FJ Ogawa R Li M Kasuya M 《The Journal of biological chemistry》2002,277(21):18986-18993
The combined effects of hyperthermia at 44 degrees C and local anesthetics on apoptosis in human histiocytic lymphoma U937 cells were investigated. When the cells were exposed to hyperthermia for l0 min marginal DNA fragmentation and nuclear fragmentation were observed. In the presence of amide-type local anesthetics further enhancement was found depending on concentration. The order of the concentration required for maximum induction was the reverse order of the lipophilicity (prilocaine > lidocaine > bupivacaine). Western blotting revealed that in hyperthermia there was initial release of Ca(2+) from the intracellular store site as indicated by increased expression of the type 1 inositol-1,4,5-trisphosphate receptor. However, the combination with lidocaine did not induce any further enhancement. Lidocaine enhanced the decrease in ATP content and the increase in intracellular Ca(2+) concentration in individual cells induced by hyperthermia. In addition, superoxide formation, decrease in the mitochondrial membrane potential, and activation of intracellular caspase-3 were found in the cells treated with hyperthermia and lidocaine. All of these were suppressed in part in the presence of the intracellular Ca(2+) ion chelator BAPTA-AM (bis-(O-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl). The present results indicate that local anesthetics at optimal concentrations enhance hyperthermia-induced apoptosis via Ca(2+)- and mitochondria-dependent pathways. Initial release of Ca(2+) from intracellular store sites caused by hyperthermia and followed by the subsequent increase in the intracellular Ca(2+) concentration and the additional activation of the mitochondrial caspase-dependent pathway (partly regulated by intracellular Ca(2+) concentration) plays a crucial role in the enhancement of apoptosis induced by the combination of hyperthermia and lidocaine. 相似文献
8.
以聚丙烯酰胺凝胶电泳方法测定了331例辽宁满族新生儿脐带血血红蛋白F中Gγ/Aγ比值。结果显示:高Gγ(>80%)者4例,占1.21%,其基因频率(f)为0.00604,低Gγ(30-48%)者6例,占1.81%,其基因频率为0.00906,其余正常,Gγ平均值为65.23±6.38%。未发现AγT链。对其中八例异常者(4例高Gγ值,4例低Gγ值)的染色体DNA进行了基因图谱分析,确定4例高Gγ值者基因型有两种:Gγ-Gγ/Gγ-Aγ二例,Gγ-AGγ-Aγ/Gγ-Aγ二例;4例低Gγ值者基因型有二种,分别为:Aγ-Aγ/Gγ-Aγ二例和-GAγ/Gγ-Aγ二例。其中Aγ-Aγ基因型在中国人群中未见报道过。 相似文献
9.
10.
The islet beta cell-enriched MafA activator is a key regulator of insulin gene transcription 总被引:13,自引:0,他引:13
Zhao L Guo M Matsuoka TA Hagman DK Parazzoli SD Poitout V Stein R 《The Journal of biological chemistry》2005,280(12):11887-11894