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Relationships among KRAS mutation status,expression of RAS pathway signaling molecules,and clinicopathological features and prognosis of patients with colorectal cancer 预览
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作者 Xiang-Bin Wan Ai-Qin Wang +6 位作者 Jian Cao Zhi-Chuang Dong Ning Li Sen Yang Miao-Miao Sun Zhi Li Su-Xia Luo 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第7期808-823,共16页
BACKGROUND The RAS/RAF/MEK/ERK and PI3K/AKT/mTOR signaling pathways all belong to mitogen-activated protein kinase(MAPK)signaling pathways,Mutations in any one of the upstream genes(such as the RAS gene or the BRAF ge... BACKGROUND The RAS/RAF/MEK/ERK and PI3K/AKT/mTOR signaling pathways all belong to mitogen-activated protein kinase(MAPK)signaling pathways,Mutations in any one of the upstream genes(such as the RAS gene or the BRAF gene)may be transmitted to the protein through transcription or translation,resulting in abnormal activation of the signaling pathway.This study investigated the relationship between the KRAS gene mutation and the clinicopathological features and prognosis of colorectal cancer(CRC),and the effect of KRAS mutations on its associated proteins in CRC,with an aim to clarify the cause of tumor progression and drug resistance caused by mutation of the KRAS gene.AIM To investigate the KRAS gene and RAS pathway signaling molecules in CRC and to analyze their relationship with clinicopathological features and prognosis METHODS Colorectal cancer tissue specimens from 196 patients were analyzed for KRAS mutations using quantitative polymerase chain reaction and for KRAS,BRAF,MEK,and ERK protein expression levels using immunohistochemistry of tumor microarrays.To analyze differences of RAS pathway signaling molecule expression levels in different KRAS gene status,the relationships between these parameters and clinicopathological features,4-year progression-free survival,and overall survival were analyzed by independent sample t test,Kaplan-Meier plots,and the log-rank test.Predictors of overall and disease-free survival were assessed using a Cox proportional hazards model.RESULTS Of the 196 patients,62(32%)carried mutations in codon 12(53/62)or codon 13(9/62)in exon 2 of the KRAS gene.KRAS,BRAF,ERK,and MEK protein expression was detected in 71.4%,78.8%,64.3%,and 50.8%of CRC tissues,respectively.There were no significant differences between KRAS mutation status and KRAS,BRAF,MEK,or ERK protein levels.Positive expression of KRAS and ERK was associated with poor tumor differentiation,and KRAS expression was also associated with age<56 years.MEK expression was significantly associated with distant metastasis(P<0.05).T 展开更多
关键词 Colorectal cancer KRAS gene KRAS PROTEIN BRAF PROTEIN MEK PROTEIN ERK PROTEIN
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Pollen Typhae Total Flavone Inhibits Endoplasmic Reticulum Stress-Induced Apoptosis in Human Aortic-Vascular Smooth Muscle Cells through Down-Regulating PERK-eIF2α-ATF4-CHOP Pathway
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作者 CHEN Ming-tai HUANG Ruo-lan +6 位作者 OU Li-jun CHEN Ying-nan MEN Ling CHANG Xiao WANG Ling YANG Yu-zhu ZHANG Zhong 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2019年第8期604-612,共9页
Objective: To test the hypothesis that the inhibition of endoplasmic reticulum(ER) stress-induced apoptosis in oxidized low-density lipoproteins(ox-LDL)-induced human aortic-vascular smooth muscle cells(HA-VSMCs) was ... Objective: To test the hypothesis that the inhibition of endoplasmic reticulum(ER) stress-induced apoptosis in oxidized low-density lipoproteins(ox-LDL)-induced human aortic-vascular smooth muscle cells(HA-VSMCs) was associated with suppression of the protein kinase RNA-like ER kinase(PERK)-eukaryotic translation initiation factor 2α(e IF2α)-activating transcription factor 4(ATF4)-CCAAT/enhancer binding protein homologous protein(CHOP) signaling pathway by Pollen Typhae total flavone(PTF). Methods: Primary HA-VSMCs were cultured and identified. The cultured HA-VSMCs were randomized into 5 groups, including a normal control group, an ox-LDL group(70 μg/m L high ox-LDL), an HPTF group(70 μg/m L high ox-LDL+500 μg/m L PTF), an MPTF group(70 μg/m L high ox-LDL+250 μg/m L PTF), and a LPTF group(70 μg/m L high ox-LDL+100 μg/m L PTF) in the first part;and a normal control group, an ox-LDL group(70 μg/mL high ox-LDL), an MPTF group(70 μg/m L high ox-LDL+250 μg/m L PTF), a sh RNA group(transducted with PERK shRNA lentiviral particles), a scramble shRNA group(transducted with control shRNA lentiviral particles), an MPTF+ox-LDL+shRNA group(250 μg/mL PTF+70 μg/mL high ox-LDL+PERK shRNA lentiviral particles) and an ox-LDL+shRNA group(70 μg/mL high ox-LDL+PERK shRNA lentiviral particles) in the second part. The protein expression levels of ER-associated apoptosis proteins were detected by Western blot, and their m RNA expression levels were detected by quantitative real-time reverse transcription-polymerase chain reaction. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay was applied to test cel viability, and the level of apoptosis was monitored by flow cytometry. Results: The MTT assay and flow cytometry showed that the ox-LDL group had a significant increase in apoptosis, which was attenuated in PTF treatment groups and sh RNA groups. Moreover, the ox-LDL group had increased protein and m RNA levels of binding immunoglobulin protein and ER-associated apoptosis proteins, such as PERK, 展开更多
关键词 Pollen Typhae total flavone endoplasmic reticulum stress PROTEIN KINASE RNA-like endoplasmic reticulum kinase-eukaryotic translation initiation FACTOR 2a -activating transcription FACTOR 4-CCAAT/enhancer binding PROTEIN homologous PROTEIN PATHWAY apoptosis vulnerable atherosclerotic plaque
Protein microarray analysis of cytokine expression changes in distal stumps after sciatic nerve transection 预览
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作者 Xiao-Qing Cheng Xue-Zhen Liang +9 位作者 Shuai Wei Xiao Ding Gong-Hai Han Ping Liu Xun Sun Qi Quan He Tang Qing Zhao Ai-Jia Shang Jiang Peng 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第3期503-511,共9页
A large number of chemokines,cytokines,other trophic factors and the extracellular matrix molecules form a favorable microenvironment for peripheral nerve regeneration.This microenvironment is one of the major factors... A large number of chemokines,cytokines,other trophic factors and the extracellular matrix molecules form a favorable microenvironment for peripheral nerve regeneration.This microenvironment is one of the major factors for regenerative success.Therefore,it is important to investigate the key molecules and regulators affecting nerve regeneration after peripheral nerve injury.However,the identities of specific cytokines at various time points after sciatic nerve injury have not been determined.The study was performed by transecting the sciatic nerve to establish a model of peripheral nerve injury and to analyze,by protein microarray,the expression of different cytokines in the distal nerve after injury.Results showed a large number of cytokines were up-regulated at different time points post injury and several cytokines,e.g.,ciliary neurotrophic factor,were downregulated.The construction of a protein-protein interaction network was used to screen how the proteins interacted with differentially expressed cytokines.Kyoto Encyclopedia of Genes and Genomes pathway and Gene ontology analyses indicated that the differentially expressed cytokines were significantly associated with chemokine signaling pathways,Janus kinase/signal transducers and activators of transcription,phosphoinositide 3-kinase/protein kinase B,and notch signaling pathway.The cytokines involved in inflammation,immune response and cell chemotaxis were up-regulated initially and the cytokines involved in neuronal apoptotic processes,cell-cell adhesion,and cell proliferation were up-regulated at 28 days after injury.Western blot analysis showed that the expression and changes of hepatocyte growth factor,glial cell line-derived neurotrophic factor and ciliary neurotrophic factor were consistent with the results of protein microarray analysis.The results provide a comprehensive understanding of changes in cytokine expression and changes in these cytokines and classical signaling pathways and biological functions during Wallerian degeneration,as well as a bas 展开更多
关键词 cytokines distal stump gene ontology Kyoto Encyclopedia of Genes and Genomes pathway peripheral nerve injury protein microarray protein-protein interaction network Wallerian degeneration
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Chemical synthesis and structure determination of venom toxins
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作者 Bobo Dang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第7期1369-1373,共5页
Venom toxins are widely spread in nature, adopting diverse structures and functions. They often function by blocking or modulating important membrane protein targets thus can be promising therapeutic candidates and bi... Venom toxins are widely spread in nature, adopting diverse structures and functions. They often function by blocking or modulating important membrane protein targets thus can be promising therapeutic candidates and biophysical probes. In this review, we briefly discuss the total chemical synthesis of venom toxins including the different refolding strategies reported during the past decade as well as innovative approaches for structure determination. 展开更多
关键词 VENOM TOXINS Chemical PROTEIN synthesis STRUCTURE DETERMINATION PROTEIN foldin Racemic PROTEIN crystallography
Recent Progress on Functional Genomics Research of Enterovirus 71
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作者 Huiqiang Wang Yuhuan Li 《中国病毒学:英文版》 CAS CSCD 2019年第1期9-21,共13页
Enterovirus 71(EV71) is one of the main pathogens that causes hand-foot-and-mouth disease(HFMD). HFMD caused by EV71 infection is mostly self-limited;however, some infections can cause severe neurological diseases, su... Enterovirus 71(EV71) is one of the main pathogens that causes hand-foot-and-mouth disease(HFMD). HFMD caused by EV71 infection is mostly self-limited;however, some infections can cause severe neurological diseases, such as aseptic meningitis, brain stem encephalitis, and even death. There are still no effective clinical drugs used for the prevention and treatment of HFMD. Studying EV71 protein function is essential for elucidating the EV71 replication process and developing anti-EV71 drugs and vaccines. In this review, we summarized the recent progress in the studies of EV71 noncoding regions(50 UTR and 30 UTR) and all structural and nonstructural proteins, especially the key motifs involving in viral infection, replication, and immune regulation. This review will promote our understanding of EV71 virus replication and pathogenesis, and will facilitate the development of novel drugs or vaccines to treat EV71. 展开更多
关键词 ENTEROVIRUS 71 (EV71) FUNCTIONAL GENOMICS Structural PROTEIN Nonstructural PROTEIN VIRAL PROTEIN function
山西吕梁地区牛、羊乳及其制品的蛋白质组成分析研究
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作者 贺莹 《食品工业》 CAS 北大核心 2019年第2期318-321,共4页
利用考马斯亮蓝G-250法定量测定了吕梁地区的牛羊乳中的蛋白质含量;采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法(SDS-PAGE)分析了牛羊乳中的蛋白质种类。结果表明:羊乳中的蛋白质含量显著高于牛乳,新鲜牛乳的碱性磷酸酶(ALP)活力和过氧化... 利用考马斯亮蓝G-250法定量测定了吕梁地区的牛羊乳中的蛋白质含量;采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法(SDS-PAGE)分析了牛羊乳中的蛋白质种类。结果表明:羊乳中的蛋白质含量显著高于牛乳,新鲜牛乳的碱性磷酸酶(ALP)活力和过氧化物酶(PLO)活力均显著高于新鲜羊乳。牛羊乳中蛋白质的种类差别比较的最佳试验方案:分离胶、浓缩胶浓度分别为12.5%和5%,电压分别为150 V和120 V。从电泳图谱可知:牛乳中的α-酪蛋白含量比羊乳高,而分子量却小于羊乳;牛乳中的β-酪蛋白分子量小于羊乳。因此,α-酪蛋白和β-酪蛋白可作为电泳法区别牛羊乳的特征性蛋白条带。 展开更多
关键词 蛋白质 蛋白提取 蛋白质含量测定 不连续电泳
Biophysical characterization and ligand-binding properties of the elongation factor Tu from Mycobacterium tuberculosis
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作者 Juanjuan Yang Jing Hong +4 位作者 Ling Luo Ke Liu Chun Meng Zhi-liang Ji Donghai Lin 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2019年第2期139-149,共11页
Mycobacterium tuberculosis(Mtb)is the key devastating bacterial pathogen responsible for tuberculosis.Increasing emergence of multi-drug-resistant,extensively drug-resistant,and rifampicin/isoniazid-resistant strains ... Mycobacterium tuberculosis(Mtb)is the key devastating bacterial pathogen responsible for tuberculosis.Increasing emergence of multi-drug-resistant,extensively drug-resistant,and rifampicin/isoniazid-resistant strains of Mtb makes the discovery of validated drug targets an urgent priority.As a vital translational component of the protein biosynthesis system,elongation factor Tu(EF-Tu)is an important molecular switch responsible for selection and binding of the cognate aminoacyl-tRNA to the acceptor site on the ribosome.In addition,EF-Tu from Mtb(MtbEF-Tu)is involved in the initial step of trans-translation which is an effective system for rescuing the stalled ribosomes from non-stop translation complexes under stress conditions.Given its crucial role in protein biosynthesis,EF-Tu is identified as an excellent molecular target for drug design.Here,we reported the recombinant expression,purification,biophysical characterization,and structural modeling of the MtbEF-Tu protein.Our results demonstrated that prokaryotic expression plasmids of pET28a-MtbEF-Tu could be expressed efficiently in Escherichia coli.We successfully purified the 6× His-tagged proteins with a yield of 16.8 mg from 1 l of Luria Bertani medium.Dynamic light scattering experiments showed that MtbEF-Tu existed in a monomeric form,and circular dichroism experiments indicated that MtbEF-Tu was well structured.Moreover,isothermal titration calorimetry experiments displayed that the purified MtbEF-Tu protein possessed intermediate binding affinities for guanosine-5′-triphosphate(GTP)and GDP.The GTP/GDP-binding sites were predicted by flexible molecular docking approach which reveals that GTP/GDP binds to MtbEF-Tu mainly through hydrogen bonds.Our work lays the essential basis for further structural and functional studies of MtbEF-Tu as well as MtbEF-Tu-related novel drug developments. 展开更多
关键词 tuberculosis MtbEF-Tu PROTEIN BIOSYNTHESIS PROTEIN expression and purification protein-guanine NUCLEOTIDE interaction
Impact of bacterial chaperonin GroEL-GroES on bacteriorhodopsin folding and membrane integration
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作者 Xinwei Lu Baomei Xu +6 位作者 Haiyan Sun Junting Wei Haixia Chi Naseer Ullah Khan Xiaojuan Wang Xiaoqiang Wang Fang Huang 《生物物理学报:英文版》 CSCD 2019年第3期133-144,共12页
Our understanding of molecular chaperone function in membrane protein biogenesis lags far behind that in soluble protein biogenesis. Through a combined approach including isothermal titration calorimetry, UV-Vis spect... Our understanding of molecular chaperone function in membrane protein biogenesis lags far behind that in soluble protein biogenesis. Through a combined approach including isothermal titration calorimetry, UV-Vis spectroscopy, and fluorescence spectroscopy, the behavior of ATP-dependent chaperonin GroEL-GroES, a paradigmatic chaperone of soluble protein folding, was investigated in the refolding of membrane protein bacteriorhodopsin (BR) and its membrane insertion. We found that BR bound asymmetrically to the double-ring GroEL, w让h a much higher affinity when it was partially denatured. GroEL alone showed a clear influence on BR refolding, but the presence of ATP was necessary to significantly enhance both the rate and yield of the GroEL-mediated folding, in contrast to the adverse effect of GroES on the folding yield. However;synergy between ATP and GroES was shown to be required not only for releasing high-affinity BR species from GroEL, but also for unfolding and rescuing the misfolded conformers complexed to GroEL. This is consistent with the observation that maximum rate enhancement of BR refolding or assembly with the prepared inverted membrane vesicles was achieved when the complete chaperonin system was used. Our results support the iterative unfolding mechanism of GroEL activity previously proposed for soluble proteins, whereby GroEL might perform repeated unfolding and release of BR, thus offering additional opportunities for timely folding or membrane integration. This work provides important information on the convergence of folding of membrane and soluble proteins in light of folding pathways and the role of molecular chaperones. 展开更多
关键词 CHAPERONIN MEMBRANE PROTEIN MEMBRANE reconstitution PROTEIN FOLDING PROTEIN structure
Navigating the dynamic landscape of alpha-synuclein morphology:a review of the physiologically relevant tetrameric conformation 预览
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作者 Heather RLucas Ricardo DFernández 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第3期407-415,共9页
N-acetylatedα-synuclein(αSyn)has long been established as an intrinsically disordered protein associated with a dysfunctional role in Parkinson’s disease.In recent years,a physiologically relevant,higher order conf... N-acetylatedα-synuclein(αSyn)has long been established as an intrinsically disordered protein associated with a dysfunctional role in Parkinson’s disease.In recent years,a physiologically relevant,higher order conformation has been identified as a helical tetramer that is tailored by buried hydrophobic interactions and is distinctively aggregation resistant.The canonical mechanism by which the tetramer assembles remains elusive.As novel biochemical approaches,computational methods,pioneering purification platforms,and powerful imaging techniques continue to develop,puzzling information that once sparked debate as to the veracity of the tetramer has now shed light upon this new counterpart inαSyn neurobiology.Nuclear magnetic resonance and computational studies on multimericαSyn structure have revealed that the protein folding propensity is controlled by small energy barriers that enable large scale reconfiguration.Alternatively,familial mutations ablate tetramerization and reconfigure polymorphic fibrillization.In this review,we will discuss the dynamic landscape ofαSyn quaternary structure with a focus on the tetrameric conformation. 展开更多
关键词 ALPHA-SYNUCLEIN amyloid fibrils intrinsically disordered protein MULTIMER N-ACETYLATION OLIGOMER Parkinson’s disease protein folding protein structure TETRAMER
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考马斯亮蓝法检测不同乳中乳清蛋白含量
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作者 聂昌宏 郑欣 +4 位作者 阿依居来克·卡得尔 李欣荣 阿地力江·依米提 郭伟 高晓黎 《食品安全质量检测学报》 CAS 2019年第5期1138-1142,共5页
目的建立考马斯亮蓝法(coomassie brilliant blue method, CCB)检测乳品中蛋白质的方法,并对几种常见乳中总蛋白质含量及乳清蛋白含量进行检测比较。方法用考马斯亮蓝G-250显色,以牛血清蛋白为对照品,采用可见分光光度法在检测波长595n... 目的建立考马斯亮蓝法(coomassie brilliant blue method, CCB)检测乳品中蛋白质的方法,并对几种常见乳中总蛋白质含量及乳清蛋白含量进行检测比较。方法用考马斯亮蓝G-250显色,以牛血清蛋白为对照品,采用可见分光光度法在检测波长595nm处测定各种乳中蛋白质的含量。结果该方法在0.005~0.1 mg/mL范围内与吸光度呈现良好的线性关系(r=0.9995),回收率为99.45%、相对标准偏差(relative standard deviation,RSD)为2.03%;不同种类乳中蛋白质含量存在差别,乳清蛋白占比也有很大的不同。结论考马斯亮蓝法检测蛋白,显色灵敏,具有简便,快捷,成本低等特点。各种乳蛋白检测比较中,马乳的乳清蛋白占比最接近母乳,这为马乳的进一步开发提供了新的理论基础。 展开更多
关键词 考马斯亮蓝法 蛋白质 乳清蛋白
Differential expression of glial cell line-derived neurotrophic factor splice variants in the mouse brain 预览
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作者 Xiao-He Gu Heng Li +4 位作者 Lin Zhang Tao He Xiang Chai He Wei Dian-Shuai Gao 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期270-276,共7页
Glial cell line-derived neurotrophic factor(GDNF) plays a critical role in neuronal survival and function. GDNF has two major splice variants in the brain,α-pro-GDNF and β-pro-GDNF, and both isoforms have strong neu... Glial cell line-derived neurotrophic factor(GDNF) plays a critical role in neuronal survival and function. GDNF has two major splice variants in the brain,α-pro-GDNF and β-pro-GDNF, and both isoforms have strong neuroprotective effects on dopamine neurons. However, the expression of the GDNF splice variants in dopaminergic neurons in the brain remains unclear. Therefore, in this study, we investigated the mRNA and protein expression of α-and β-pro-GDNF in the mouse brain by real-time quantitative polymerase chain reaction, using splice variant-specific primers, and western blot analysis. At the mRNA level,β-pro-GDNF expression was significantly greater than that of α-pro-GDNF in the mouse brain. In contrast, at the protein level,α-pro-GDNF expression was markedly greater than that of β-pro-GDNF. To clarify the mechanism underlying this inverse relationship in mRNA and protein expression levels of the GDNF splice variants, we analyzed the expression of sorting protein-related receptor with A-type repeats(SorLA) by real-time quantitative polymerase chain reaction. At the mRNA level, SorLA was positively associated with β-pro-GDNF expression, but not with α-pro-GDNF expression. This suggests that the differential expression of α-and β-pro-GDNF in the mouse brain is related to SorLA expression. As a sorting protein, SorLA could contribute to the inverse relationship among the mRNA and protein levels of the GDNF isoforms. This study was approved by the Animal Ethics Committee of Xuzhou Medical University, China on July 14, 2016. 展开更多
关键词 Δ78 locus BRAIN region dopaminergic neurons GLIAL cell line-derived NEUROTROPHIC factor mouse BRAIN precursor protein α-pro-GDNF β-pro-GDNF sorting protein-related receptor with A-type REPEATS splice variants
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Decoding the Structural Keywords in Protein Structure Universe
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作者 Wessam Elhefnawy Min Li +1 位作者 Jian-Xin Wang Yaohang Li 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期3-15,共13页
Although the protein sequence-structure gap continues to enlarge due to the development of high-throughput sequencing tools,the protein structure universe tends to be complete without proteins with novel structural fo... Although the protein sequence-structure gap continues to enlarge due to the development of high-throughput sequencing tools,the protein structure universe tends to be complete without proteins with novel structural folds deposited in the protein data bank (PDB)recently.In this work,we identify a protein structural dictionary (Frag-K)composed of a set of backbone fragments ranging from 4 to 20 residues as the structural "keywords"that can effectively distinguish between major protein folds.We firstly apply randomized spectral clustering and random forest algorithms to construct representative and sensitive protein fragment libraries from a large scale of high-quality,non-homologous protein structures available in PDB.We analyze the impacts of clustering cut-offs on the performance of the fragment hbraries.Then,the Frag-K fragments are employed as structural features to classify protein structures in major protein folds defined by SCOP (Structural Classification of Proteins).Our results show that a structural dictionary with N400 4-to 20-residue Frag-K fragments is capable of classifying major SCOP folds with high accuracy. 展开更多
关键词 PROTEIN FRAGMENT FOLD recognition PROTEIN structure UNIVERSE
不同花源蜂蜜蛋白质组分及提取方法的比较 预览
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作者 张颖 张光艳 +1 位作者 王宇翔 曹炜 《食品与发酵工业》 CAS CSCD 北大核心 2019年第14期91-96,共6页
比较中国不同花源蜂蜜蛋白质组分及提取方法的差异。以枣花蜜、荆条蜜、龙眼蜜、土蜂蜜、洋槐蜜和油菜蜜为研究对象,比较6种蜂蜜蛋白质电泳行为差异;采用超滤法和硫酸-钨酸钠沉淀法提取蜂蜜蛋白,分析2种蛋白质提取方法的适用性及分离效... 比较中国不同花源蜂蜜蛋白质组分及提取方法的差异。以枣花蜜、荆条蜜、龙眼蜜、土蜂蜜、洋槐蜜和油菜蜜为研究对象,比较6种蜂蜜蛋白质电泳行为差异;采用超滤法和硫酸-钨酸钠沉淀法提取蜂蜜蛋白,分析2种蛋白质提取方法的适用性及分离效果。6种不同花源蜂蜜蛋白质相对分子质量集中在14.4~97.4kDa,但蛋白质组成和含量在品种间差异明显,而枣花蜜、龙眼蜜和土蜂蜜在>97.4kDa存在较多高分子质量蛋白;超滤法适合提取枣花蜜、荆条蜜、洋槐蜜和油菜蜜蛋白质,而龙眼蜜和土蜂蜜适合用硫酸-钨酸钠沉淀法分离,2种方法获得的6种蜂蜜蛋白在SDS-PAGE和RP-HPLC图谱中呈现明显的分子质量和疏水性差异。这为基于蛋白质差异构建蜂蜜花源鉴别技术奠定理论基础。 展开更多
关键词 蜂蜜 蛋白质 蛋白质提取 电泳 反相高效液相色谱
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Effects of High Hydrostatic Pressure on the Solubilities and Structures of Alaska Pollock Protein 预览
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作者 LIU Chuyi MA Xiaoming +1 位作者 Li Bo LI Bafang 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期413-419,共7页
Alaska pollock is an important protein source which is extensively used in the food industry.Pollock protein isolates(PPI)with significantly enriched protein contents could be prepared using isoelectric solubilization... Alaska pollock is an important protein source which is extensively used in the food industry.Pollock protein isolates(PPI)with significantly enriched protein contents could be prepared using isoelectric solubilization/precipitation(ISP)processing;however,the functional properties of this process is limited by the large amount of water-insoluble proteins.In this study,we investigated the influence of high hydrostatic pressure(HHP)treatment on the solubility and structural changes of PPI.PPI obtained using ISP is treated with hydrostatic pressures of 200,300,400,and 500 MPa for up to 15 min,and the HHP-treated samples were observed to exhibit significantly improved solubilities.Further biochemical assays reveal that the continuous HHP treatments reduce the contents of free sulfhydryl groups and promote the formation of macromolecules with better water solubilities,which may induce the solubility improvements of the HHP-treated PPI.Our results indicate that HHP can be utilized to effectively prepare highly water-soluble Alaska pollock protein in food processing. 展开更多
关键词 Alaska POLLOCK PROTEIN isolate(PPI) SOLUBILITY high HYDROSTATIC pressure PROTEIN structure
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Transcriptional dysregulation in neurodegenerative diseases:who tipped the balance of Yin Yang 1 in the brain? 预览
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作者 Zhefan Stephen Chen Ho Yin Edwin Chan 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第7期1148-1151,共4页
Yin Yang 1(YY1)is a multi-functional transcription factor that regulates gene expression in a range of cell types,including neurons.It controls neuronal differentiation,as well as neuronal specification and migration ... Yin Yang 1(YY1)is a multi-functional transcription factor that regulates gene expression in a range of cell types,including neurons.It controls neuronal differentiation,as well as neuronal specification and migration during the development of the mammalian nervous system.Besides,YY1 also mediates the transcription of genes that are required for neuronal survival.An impairment of the transcriptional function of YY1 causes neuronal death.This review summarizes recent research findings that unveil the dysfunction of YY1 in multiple neurodegenerative disorders.The expression of disease proteins perturbs the function of YY1 via distinct molecular mechanisms,including recruitment to protein aggregates,protein degradation and aberrant nuclear/cytoplasmic shuttling.Understanding the pathogenic roles of YY1 will further broaden our knowledge of the disease mechanisms in distinct neurodegenerative disorders. 展开更多
关键词 Alzheimer’s disease amyotrophic lateral SCLEROSIS neurodegeneration PROTEIN aggregates recruitment PROTEIN degradation SUBCELLULAR localization TRANSCRIPTIONAL regulation YIN Yang 1
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中国境内4种常见蛇毒的蛋白质组学研究 预览
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作者 张经硕 向平 沈敏 《蛇志》 2019年第2期175-177,183共4页
目的研究中华眼镜蛇毒、尖吻蝮蛇毒、银环蛇毒和金环蛇毒的蛋白构成。方法采用鸟枪蛋白质组学策略结合无标记定量方法检测4种蛇毒的蛋白种类及丰度。结果金属蛋白酶Aculysin-2、金属蛋白酶前体H4、心脏毒素1e、磷脂酶B81b、Thaicobrin... 目的研究中华眼镜蛇毒、尖吻蝮蛇毒、银环蛇毒和金环蛇毒的蛋白构成。方法采用鸟枪蛋白质组学策略结合无标记定量方法检测4种蛇毒的蛋白种类及丰度。结果金属蛋白酶Aculysin-2、金属蛋白酶前体H4、心脏毒素1e、磷脂酶B81b、Thaicobrin、乙酰胆碱酯酶在多种毒液中均被检出,可能成为影响免疫鉴定方法准确度的因素。结论揭示不同蛇毒的蛋白构成的异同可以为蛇伤鉴定方法的开发与蛇伤救治提供基础。 展开更多
关键词 蛇毒 蛋白质 蛋白质组学 无标记定量 蛋白质丰度
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蛋白质互作技术研究进展 预览
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作者 卢艳艳 王超 侍福梅 《湖北农业科学》 2019年第12期5-10,21共7页
蛋白质作为细胞活性及功能的执行者,以复杂有序的动态互作协调着细胞的增殖与分化、衰老与死亡以及环境应答等各种重要生理过程。重点介绍了酵母双杂交系统、双分子荧光互补、噬菌体展示技术、荧光共振能量转移技术、谷胱甘肽巯基转移... 蛋白质作为细胞活性及功能的执行者,以复杂有序的动态互作协调着细胞的增殖与分化、衰老与死亡以及环境应答等各种重要生理过程。重点介绍了酵母双杂交系统、双分子荧光互补、噬菌体展示技术、荧光共振能量转移技术、谷胱甘肽巯基转移酶融合蛋白沉降技术、免疫共沉淀技术等蛋白质互作研究技术的原理及在生物学中的应用,以及生物信息学在蛋白质互作研究中的应用,并对目前及未来蛋白质互作技术的发展方向进行了探讨。 展开更多
关键词 蛋白质 生物信息 蛋白质互作
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小麦籽粒不同部位蛋白质理化特性研究进展 预览
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作者 代美瑶 巩艳菲 +1 位作者 李芳 张波 《中国粮油学报》 EI CAS CSCD 北大核心 2019年第7期132-138,共7页
制粉工序不同节点或逐层研磨的小麦粉表示籽粒从外到内不同部位的组分,因其蛋白组分含量和性质各不相同,具有不同的加工特性。明确不同部位蛋白质理化特性,可为制粉、配粉和专用粉生产提供参考。本文综述了小麦蛋白质的分类、蛋白质及... 制粉工序不同节点或逐层研磨的小麦粉表示籽粒从外到内不同部位的组分,因其蛋白组分含量和性质各不相同,具有不同的加工特性。明确不同部位蛋白质理化特性,可为制粉、配粉和专用粉生产提供参考。本文综述了小麦蛋白质的分类、蛋白质及其组分在小麦籽粒中的分布,以及不同组分蛋白质的理化性质。小麦籽粒由内向外,蛋白质含量逐渐增大,面筋含量先逐渐增加后降低。越接近外层胚乳或糊粉层,清蛋白、球蛋白、麦醇溶蛋白、麦谷蛋白、十二烷基硫酸钠可溶蛋白、谷蛋白大聚体含量、面筋指数、沉降指数等呈现逐渐增大的趋势,各蛋白质组分的增加幅度不同;面团吸水率和拉伸面积逐渐增加,延伸性逐渐降低;面团形成时间、稳定时间、拉伸阻力等变化规律不明显,总体表现为波动至较大值后降低。 展开更多
关键词 小麦 籽粒结构 蛋白质 蛋白质组分 理化特性
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Protein kinase A inhibition induces EPAC-dependent acrosomal exocytosis in human sperm
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作者 Diana Itzhakov Yeshayahu Nitzan Haim Breitbart 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第4期337-344,共8页
To in teract with the egg, the spermatozo on must un dergo several biochemical and motility modifications in the female reproductive tract, collectively called capacitation. Only capacitated sperm can undergo acrosoma... To in teract with the egg, the spermatozo on must un dergo several biochemical and motility modifications in the female reproductive tract, collectively called capacitation. Only capacitated sperm can undergo acrosomal exocytosis, near or on the egg, a process that allows the sperm to penetrate and fertilize the egg. In the present study, we investigated the invoIvement of cyclic adenosine monophosphate (cAMP)-dependent processes on acrosomal exocytosis. Inhibition of protein kinase A (PKA) at the end of capacitation induced acrosomal exocytosis. This process is cAMP-dependent;however, the addition of relatively high concentration of the membrane-permeable 8-bromo-cAMP (8Br-cAMP, 0.1 mmol l^-1) analog induced significant inhibition of the acrosomal exocytosis. The induction of acrosomal exocytosis by PKA inhibition was significantly inhibited by an exchange protein directly activated by cAMP (EPAC) ESI09 inhibitor. The EPAC selective substrate activated AE at relatively low concentrations (0.02-0.1 μmol l^1), whereas higher concerttrations (>5 pmol l^-1) were inhibitory to the AE induced by PKA inhibition. Inhibition of PKA revealed about 50% increase in intracellular cAMP levels, conditions under which EPAC can be activated to induce the AE. Induction of AE by activating the actin severing?protein, gelsolin, which causes F-actin dispersion, was inhibited by the EPAC inhibitor. The AE induced by PKA inhibition was mediated by phospholipase C activity but not by the Ca^2+-channel, CatSper. Thus, inhibition of PKA at the end of the capacitation process induced EPAC/phospholipase C-dependent acrosomal exocytosis. EPAC mediates F-actin depolymerization an d/or activation of effectors down stream to F-actin breakdown that lead to acrosomal exocytosis. 展开更多
关键词 acrosomal EXOCYTOSIS exchange PROTEIN directly activated by cyclic ADENOSINE MONOPHOSPHATE PROTEIN kinase A sperm
近红外光谱技术无损检测大米中蛋白质
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作者 刘文丽 严虞虞 +2 位作者 吴东慧 滕明攀 何诗慧 《食品工业》 CAS 北大核心 2019年第1期205-209,共5页
为建立一种无损的大米蛋白质近红外检测方法,以138份大米作为样本,分别对蛋白质和蛋白质(干基)进行近红外建模。经优化得到相应的最佳模型,两模型的内部校正决定系数R^2内分别为0.9506和0.9652,内部相对分析误差RPD内分别为4.50和5.36,... 为建立一种无损的大米蛋白质近红外检测方法,以138份大米作为样本,分别对蛋白质和蛋白质(干基)进行近红外建模。经优化得到相应的最佳模型,两模型的内部校正决定系数R^2内分别为0.9506和0.9652,内部相对分析误差RPD内分别为4.50和5.36,内部交叉验证标准差RMSECV分别为0.197和0.231,外部校正决定系数R^2外分别为0.9565和0.9741,外部相对分析误差RPD外分别为4.79和6.21,外部交叉验证标准差RMSEP分别为0.147和0.215。对比两模型,蛋白质(干基)的近红外模型具有更好的线性和预测能力,但RMSECV较蛋白质大,精密度不如蛋白质近红外模型。 展开更多
关键词 大米 近红外光谱技术 蛋白质 蛋白质(干基)
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