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Yu Zhang Jia Luo Zhe Liu Xudong Liu Ying Ma Bohang Zhang Yuxuan Chen Xiaofeng Li Zhiguo Feng Ningning Yang Dayun Feng Lei Wang Xinqiang Song 《Bioscience reports》2021,41(7)
Colorectal cancer (CRC) is one of the most common tumors worldwide and is associated with high mortality. Here we performed bioinformatics analysis, which we validated using immunohistochemistry in order to search for hub genes that might serve as biomarkers or therapeutic targets in CRC. Based on data from The Cancer Genome Atlas (TCGA), we identified 4832 genes differentially expressed between CRC and normal samples (1562 up-regulated and 3270 down-regulated in CRC). Gene ontology (GO) analysis showed that up-regulated genes were enriched mainly in organelle fission, cell cycle regulation, and DNA replication; down-regulated genes were enriched primarily in the regulation of ion transmembrane transport and ion homeostasis. Weighted gene co-expression network analysis (WGCNA) identified eight gene modules that were associated with clinical characteristics of CRC patients, including brown and blue modules that were associated with cancer onset. Analysis of the latter two hub modules revealed the following six hub genes: adhesion G protein-coupled receptor B3 (BAI3, also known as ADGRB3), cyclin F (CCNF), cytoskeleton-associated protein 2 like (CKAP2L), diaphanous-related formin 3 (DIAPH3), oxysterol binding protein-like 3 (OSBPL3), and RERG-like protein (RERGL). Expression levels of these hub genes were associated with prognosis, based on Kaplan–Meier survival analysis of data from the Gene Expression Profiling Interactive Analysis database. Immunohistochemistry of CRC tumor tissues confirmed that OSBPL3 is up-regulated in CRC. Our findings suggest that CCNF, DIAPH3, OSBPL3, and RERGL may be useful as therapeutic targets against CRC. BAI3 and CKAP2L may be novel biomarkers of the disease. 相似文献
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探讨蛋白酶体抑制剂MG132 在诱导人白血病K562细胞凋亡过程中作用.分别以不同浓度的蛋白酶体抑制剂MG132 处理人白血病细胞K562,通过MTT法检测K562细胞活力,应用Annexin Ⅴ和PI 双染的细胞流式法检测K562细胞凋亡率和细胞内活性氧(ROS) 水平,应用酶标仪法检测K562细胞内Caspase- 3活性变化的情况.结果表明,随着MG132浓度的增加,各个指标与对照组比较差异均有显著性(P<0.05):K562细胞增殖明显受到抑制;细胞凋亡率明显增加,且当MG132浓度为900 nmol/L时,细胞凋亡率达36.5 %;同时,ROS 水平和caspase- 3活性明显升高.因次,蛋白酶体抑制剂MG132可显著抑制人白血病细胞K562增殖并促进其凋亡. 相似文献
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中国松杉类植物濒危等级划分的比较 总被引:19,自引:0,他引:19
本文根据世界保护监测中心(WCMC)和国际松杉类植物专家(CSG)编制的濒危植物名录,以及中国植物红皮书(第1卷)列出中国受威胁松杉类植物共141种及变种。通过对上述三者濒危等级的比较表明,它们在中国松杉类植物濒危等级的划分上并不完全一致,主要原因是划分物种濒危等级的标准不同或资料依据不完全等。最后,作者根据1994年IUCN提出的物种受威胁等级划分标准草案(2.3版本),对中国松杉类一些濒危种类的等级划分作了初步分析和讨论。 相似文献
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Whether shrinking body size is a universal response to climate change remains controversial. Moreover, the mechanisms underlying body size shifts are poorly understood. Here, assuming that life history traits evolve to maximize fitness according to life history plasticity theory, we hypothesized that under global warming temperate multivoltine insects should emerge earlier with a smaller body mass in the early growing season, but emerge later with a larger body mass in the late season. We tested this hypothesis by conducting two field artificial warming experiments in an alpine meadow: 1) with one pre‐dispersal seed predator species (tephritid flies, Tephritis femoralis) and its two host‐plant species flowering in early and late growing seasons, respectively, and 2) with the tephritid flies and one host species with a flowering season that occupies parts of both the early and late growing seasons. These experiments were complemented by a microcosm chamber warming experiment, in which increasing and decreasing temperature trends were set to simulate temperature variation pattern in early and late growing seasons, respectively, but photoperiod was held constant. Warming generally advanced the adult emergence and decreased the body size (adult body mass) in the early season but delayed the emergence and increased the size in the late season in both field experiments, indicating that the seasonally different effects of warming on the fly body size was constant regardless of host‐plant identity. The chamber warming resulted in consistent responses of emerging timing and body size to the simulated seasonal warming, demonstrating that the temperature increase per se and its interaction with direction of temperature change, but not other correlated effects, should be primarily responsible for the observed contrasting shifts of body size at different times of the season. Our results indicate that taking into account temperate seasonal patterns of temperature variation could be of general importance for predicting animal body size changes in the warmed future. 相似文献
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东海浮游植物数量分布与优势种 总被引:16,自引:0,他引:16
根据1997~2000年东海23°30′~33°N、118°30′~128°E海域4个季节海洋调查资料,运用定量、定性方法,探讨了东海浮游植物总丰度的平面分布、季节分布及变化的动力学机制,同时还探讨了东海浮游植物优势种的生态学特征和对温盐环境适应特征。结果表明:东海浮游植物总丰度有明显的季节分布,秋季总丰度达到4季最高峰,均值为211.91×104cell.m-3,夏季次之(50.40×104cell.m-3),冬季11.34×104cell.m-3,春季(2.01×104cel.lm-3)最低。春夏季东海近海(Ⅰ和Ⅲ)高于外海(Ⅱ和Ⅳ),秋冬季东海北部外海(Ⅱ)高于近海(Ⅰ),南部近海(Ⅲ)高于外海(Ⅳ)。4季共出现优势种(Y≥0.02)11种,冬季的主要优势种为洛氏角毛藻和细弱海链藻,春季的主要优势种为洛氏角毛藻和夜光藻,夏季以拟弯角毛藻和细长翼根管藻为主要优势种,秋季优势种仅为聚生角毛藻。浮游植物的聚集强度指数为较大正值,聚集作用明显。从全年的逐步回归分析结果看,温度是影响浮游植物总丰度季节分布的主要因子,盐度是次要因子。浮游植物的11个优势种之间生存环境适应比较,洛氏角毛藻和中华盒形藻生长温度幅度较大,可以在12~28℃水温增长,因而春、夏和冬季都成为优势种。中肋骨条藻适合生长的水温范围都较小,仅为22~28℃。聚生角毛藻更小,仅21~25℃。洛氏角毛藻和中华盒形藻生长温盐度和高分布区温盐度范围比聚生角毛藻和中肋骨条藻都广,而秋季数量却低于聚生角毛藻。 相似文献
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Heparinase I from Flavobacterium heparinum, a source of diverse polysaccharidases, suffers from low yields, insufficient purity for structural studies and insolubility when expressed as a recombinant product in Escherichia coli that is devoid of glycosaminoglycan polysaccharidases. In this study, cDNA coding for the orthologue of F. heparinum heparinase I was constructed from genomic information from the mammalian gut symbiont Bacteroides thetaiotaomicron and expressed in E. coli as a fusion protein with GST at the N-terminus. This resulted in high yield (30 mg/g dry bacteria) of soluble product and facilitated one-step affinity purification to homogeneity. Purified heparinase I bearing the GST fusion exhibited a Km of 2.3 μM and Vmax of 42.7 μmol/min with a specific activity of 164 U/mg with heparin (average 12,000 Da) as substrate. The results indicate a 2-fold improvement in yield, specific activity and affinity for heparin as substrate over previous reports. The data suggest that the heparinase I from the gut symbiont exhibits a higher intrinsic affinity for heparin than that from F. heparinum. The purified GST fusion enzyme exhibited a requirement for Ca2+ and a pH optimum between 6.7 and 7.3 that was similar to the enzyme freed of the N-terminal GST portion. Our study revealed that catalytic activity of heparinase I requires a reducing environment. The GST facilitated immobilization of heparinase I in solid phase either for clinical purposes or for structural studies in absence of interference by contaminating polysaccharidases. 相似文献
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植物叶蛋白提取方法的比较 总被引:8,自引:0,他引:8
随着畜牧业的迅速发展,蛋白质饲料供应严重不足的问题日益突出。世界各国都在积极寻求开发利用蛋白质饲料资源[1]。其中开发利用植物叶蛋白是一条有效的途径[2]。我国有高等植物30000余种,可作饲料的有2000余种[3],山东省有高等植物近2400种,可... 相似文献
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