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51.
The recent genome-wide association study identified a link between vitiligo and genetic variants in the ribonuclease T2 (RNASET2) gene; however, the functional roles of RNASET2 in vitiligo pathogenesis or in melanocyte apoptosis have yet to be determined. The current study was designed to investigate the vitiligo-related expression pattern of RNASET2 and its molecular function involving apoptosis-related signaling proteins and pathways. The results showed overexpression of RNASET2 in epidermis specimens from 40 vitiligo patients compared with that from matched healthy controls. In addition, in vitro analyses indicated that overexpression of RNASET2 was inducible in cultured primary human melanocytes and keratinocytes by stress conditions, that is, exposure to UV irradiation, hydrogen peroxide, and inflammatory factors, respectively, and led to increased cell apoptosis via the tumor necrosis factor receptor-associated factor 2 (TRAF2)–caspases pathway through the physical interaction of RNASET2 with TRAF2. Thus, RNASET2 may contribute to vitiligo pathogenesis by inhibiting TRAF2 expression and, as such, RNASET2 may represent a potential therapeutic target of vitiligo.  相似文献   
52.
【目的】解析出芽短梗霉CCTCC M2012223的基因组序列信息,分析其代谢产物聚苹果酸、黑色素、普鲁兰多糖合成相关基因,为深入研究遗传多样性和代谢工程改造提供序列背景信息。【方法】使用Illumina Hi Seq高通量测序平台对出芽短梗霉CCTCC M2012223菌株进行全基因组测序,并对测序数据进行序列拼接,基因预测与功能注释,COG/GO聚类分析,比较基因组学分析等。下载其他5株出芽短梗霉基因组序列,比较分析6株菌的种内同源基因、全基因组进化以及代谢产物合成相关基因。【结果】出芽短梗霉CCTCC M2012223基因组序列全长30756831 bp,GC含量47.49%,编码9452个基因。比较基因组分析表明出芽短梗霉CCTCC M2012223的基因组组装长度最长,6株菌的同源基因数达到7092个,普鲁兰多糖和聚苹果酸合成相关基因的蛋白序列有很高的保守性。出芽短梗霉CCTCC M2012223和Aureobasidium pullulans var.melanogenum亲缘关系最近,而这2株菌的黑色素合成相关基因的蛋白序列有一些插入和突变。【结论】本研究解析了出芽短梗霉CCTCC M2012223的基因组序列信息,获得黑色素、普鲁兰多糖和聚苹果酸合成相关基因,为后续的代谢机制解析和改造提供相关依据。  相似文献   
53.
Three-dimensional quantitative structure–activity relationship (3D-QSAR) studies were performed on a series of substituted 1,4-dihydroindeno[1,2-c]pyrazoles inhibitors, using molecular docking and comparative molecular field analysis (CoMFA). The docking results from GOLD 3.0.1 provide a reliable conformational alignment scheme for the 3D-QSAR model. Based on the docking conformations and alignments, highly predictive CoMFA model was built with cross-validated q 2 value of 0.534 and non-cross-validated partial least-squares analysis with the optimum components of six showed a conventional r 2 value of 0.911. The predictive ability of this model was validated by the testing set with a conventional r 2 value of 0.812. Based on the docking and CoMFA, we have identified some key features of the 1,4-dihydroindeno[1,2-c]pyrazoles derivatives that are responsible for checkpoint kinase 1 inhibitory activity. The analyses may be used to design more potent 1,4-dihydroindeno[1,2-c]pyrazoles derivatives and predict their activity prior to synthesis.  相似文献   
54.
It is well known that nitric oxide (NO) enhances salt tolerance of glycophytes. However, the effect of NO on modulating ionic balance in halophytes is not very clear. This study focuses on the role of NO in mediating K+/Na+ balance in a mangrove species, Kandelia obovata Sheue, Liu and Yong. We first analyzed the effects of sodium nitroprusside (SNP), an NO donor, on ion content and ion flux in the roots of K. obovata under high salinity. The results showed that 100 μM SNP significantly increased K+ content and Na+ efflux, but decreased Na+ content and K+ efflux. These effects of NO were reversed by specific NO synthesis inhibitor and scavenger, which confirmed the role of NO in retaining K+ and reducing Na+ in K. obovata roots. Using western-blot analysis, we found that NO increased the protein expression of plasma membrane (PM) H+-ATPase and vacuolar Na+/H+ antiporter, which were crucial proteins for ionic balance. To further clarify the molecular mechanism of NO-modulated K+/Na+ balance, partial cDNA fragments of inward-rectifying K+ channel, PM Na+/H+ antiporter, PM H+-ATPase, vacuolar Na+/H+ antiporter and vacuolar H+-ATPase subunit c were isolated. Results of quantitative real-time PCR showed that NO increased the relative expression levels of these genes, while this increase was blocked by NO synthesis inhibitors and scavenger. Above results indicate that NO greatly contribute to K+/Na+ balance in high salinity-treated K. obovata roots, by activating AKT1-type K+ channel and Na+/H+ antiporter, which are the critical components in K+/Na+ transport system.  相似文献   
55.
56.

Objectives

FBXW7 acts as a tumour suppressor by targeting at various oncoproteins for ubiquitin‐mediated degradation. However, the clinical significance and the involving regulatory mechanisms of FBXW7 manipulation of NSCLC regeneration and therapy response are not clear.

Materials and Methods

Immunohistochemical staining and qRT‐PCR were applied to detect FBXW7 and Snai1 expression in 100 samples of NSCLC and matched tumour‐adjacent tissues. FBXW7 manipulation of cancer biological functions were studied by using MTT assay, immunoblotting, flow cytometry, transwells, wound healing assay, and sphere‐formation assays. Immunofluorescence and co‐immunoprecipitation were used to analyse the possible interaction between Snai1 and FBXW7.

Results

We detected the decreased FBXW7 expression in majority of the NSCLC tissues, and lower FBXW7 level was correlated with advanced TNM stage. Furthermore, those patients with decreased FBXW7 expression tend to have both poorer 5‐year survival outcomes, and shorter disease‐free survival, comparing to those with higher FBXW7 levels. Functionally, we found that FBXW7 enforcement suppressed NSCLC progression by inducing cell growth arrest, increasing chemo‐sensitivity and inhibiting Epithelial‐mesenchymal Transition (EMT) progress. Results further showed that FBXW7 could interact with Snai1 directly to degrade its expression through ubiquitylating alternation in NSCLC, which could be partially abrogated by restoring Snai1 expression.

Conclusions

FBXW7 conduction of tumour suppression was partly through degrading Snai1 directly for ubiquitylating regulation in NSCLC
  相似文献   
57.
沙丘稀有种准噶尔无叶豆花部综合特征与传粉适应性   总被引:1,自引:0,他引:1  
植物花部特征进化与传粉适应性一直是进化生态学领域关注的核心问题之一。以古尔班通古特沙漠自然生长的准噶尔无叶豆为对象,对其花部特征和传粉特性进行了野外观察和室内的分析研究。结果表明:种群花期历时21 d,花序花期历时7-12 d,单花花期一般3 d,若遇阴雨天气,花期可延长1-2 d,整个花期龙骨瓣一直保持闭合状态。单花10枚花药在旗瓣微张时已全部完成散粉。准噶尔无叶豆主要靠分泌花蜜、鲜艳的花色以及旗瓣基部的黄色辐射状纹理结构吸引传粉者。准噶尔无叶豆花期的有效传粉者为4种蜂类昆虫,它们的平均访花频率为(7.75±0.57)次·花-1·d-1,访花高峰期表现为三峰型: 13:00-14:00,16:00-17:00和19:00-20:00。准噶尔无叶豆人工套袋实验表明该种为自交亲和型,主动自交少见,生殖成功依赖传粉者。胚珠成功受精至果实完全成熟阶段存在自交衰退,柱头角质层结构和花粉刷结构是准噶尔无叶豆在进化过程中形成的减少自交,倾向异交的机制。  相似文献   
58.
为了建立最佳的人妊娠子宫平滑肌细胞的原代培养方法和初步检测子宫平滑肌细胞中Transgelin蛋白的表达,采用组织块贴壁法和酶消化法进行人妊娠子宫平滑肌原代培养.发现组织贴块培养的细胞呈典型的梭状肌细胞样生长,经过传代纯化,通过免疫细胞化学方法检测平滑肌肌动蛋白(smooth muscle acting,SMA)进行细胞鉴定及检测Trangsgelin(smooth muscle 22 alpha,SM22-α)蛋白,得到SMA、snd2-α荧光免疫细胞化学染色为阳性.结果表明组织贴块法对妊娠子宫平滑肌细胞损伤小,可获得状态良好的纯净的子宫平滑肌细胞,子宫平滑肌细胞中大量表达sm2-α,为进一步研究sm22-α在子宫平滑肌细胞中作用打下基础.  相似文献   
59.
不同林地清理方式对杉木林土壤肥力的影响   总被引:23,自引:1,他引:23  
研究了杉木林采伐迹地及采伐后的炼山迹地的土壤物理性质、养分含量、微生物数量和酶活性.结果表明,采伐迹地的非毛管孔隙比杉木林地增加23%,自然含水量和毛管持水量则下降2%;炼山迹地土壤容重比杉木林地增加10%,非毛管孔隙、自然含水量和毛管持水量分别下降61%、48%和26%.采伐迹地有机质、全N、全P和全K含量分别比杉木林地下降14%、14%、3%和22%,炼山迹地分别下降37%、37%、47%和7%.采伐迹地碱解N和有效K含量分别比杉木林地增加24%和31%,有效P含量比杉木林地下降1%;炼山迹地的碱解N、有效P和有效K含量分别比杉木林地下降2%、43%和40%.采伐迹地的细菌、真菌和放线菌数量比杉木林地增加1.4、11.3和0.8倍;炼山迹地细菌数量比杉木林地减少24%,真菌和放线菌数量增加了.0和0.倍.采伐迹地脲酶、过氧化氢酶和纤维素分解酶活性分别为杉木林地1.9、1.6和2.1倍,而炼山迹地分别为后者的3.4%、90%和106%.湿润土壤有机质、全N和全P含量高,疏松多孔的土壤有利于碱解N、速效P、速效K积累和脲酶活性的增加.真菌数量随毛管孔隙的增加而减少.通气良好有利于提高土壤过氧化氢酶活性.  相似文献   
60.
溴氨酸降解菌株的分离和特性   总被引:4,自引:0,他引:4  
从化工厂污泥中中分离到4个对蒽醌染料中间体溴氨酸有显降解和脱色作用的菌株。经鉴定,4株菌均为假单胞菌属(Pseudomonas sp.)。脱色效果最好的N1菌株能以溴酸为唯一碳源生长,其脱色效果受温度和pH影响较大,最佳生长条件是30℃,pH7.2。  相似文献   
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