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Deep Learning Algorithm for Detection of Protein Remote Homology
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作者 Fahriye Gemci Turgay Ibrikci Ulus Cevik 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3703-3713,共11页
The study aims to find a successful solution by using computer algorithms to detect remote homologous proteins,which is a significant problem in the bioinformatics field.In this experimental study,structural classific... The study aims to find a successful solution by using computer algorithms to detect remote homologous proteins,which is a significant problem in the bioinformatics field.In this experimental study,structural classification of proteins(SCOP)1.53,SCOP benchmark,and the newly created SCOP protein database from the structural classification of proteins—extended(SCOPe)2.07 were used to detect remote homolog proteins.N-gram method and then Term Frequency-Inverse Document Frequency(TF-IDF)weighting were performed to extract features of the protein sequences taken from these databases.Next,a smoothing process on the obtained features was performed to avoid misclassification.Finally,the proteins with balanced features were classified into remote homologs using the built deep learning architecture.As a result,remote homologous proteins have been detected with novel deep learning architecture using both negative and positive protein instances with a mean accuracy of 89.13%and a mean relative operating characteristic(ROC)score of 88.39%.This experiment demonstrated the following:1)The successful outcome of this study in detecting remote homology is auspicious in discovering new proteins and thus in drug discovery in medicine.2)Natural language processing(NLP)techniques were used successfully in bioinformatics,3)the importance of choosing the correct n-value in the n-gram process,4)the necessity of using not only positive but negative instances in a classification problem,and 5)how effective the processes,such as smoothing,are in the classification accuracy in an imbalanced dataset.6)The deep learning architecture gives better results than the support vector machine(SVM)model on the smoothed data to detect proteins’remote homology. 展开更多
关键词 Bioinformatics deep learning N-GRAM remote homolog protein text classification TF-IDF weighting
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Subcellular Distribution and Chemical Forms of Cadmium in the Medicine Food Homology Plant Platycodon grandiflorum(Jacq.)A.DC.
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作者 Jia An Xiang Wang +7 位作者 Yajiang Jing Jianping Huang Qilong Wang Gang Zhang Jing Gao Liang Peng Wenli Huang Yonggang Yan 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第5期1405-1420,共16页
Although Platycodon grandiflorum(Jacq.)A.DC.is a renowned medicine food homology plant,reports of excessive cadmium(Cd)levels are common,which affects its safety for clinical use and food consumption.To enable its Cd ... Although Platycodon grandiflorum(Jacq.)A.DC.is a renowned medicine food homology plant,reports of excessive cadmium(Cd)levels are common,which affects its safety for clinical use and food consumption.To enable its Cd levels to be regulated or reduced,it is necessary to first elucidate the mechanism of Cd uptake and accumulation in the plant,in addition to its detoxification mechanisms.This present study used inductively couple plasma-mass-spectrometry to analyze the subcellular distribution and chemical forms of Cd in different tissues of P.grandiflorum.The experimental results showed that Cd was mainly accumulated in the roots[predominantly in the cell wall(50.96%-61.42%)],and it was found primarily in hypomobile and hypotoxic forms.The proportion of Cd in the soluble fraction increased after Cd exposure,and the proportion of insoluble phosphate Cd and oxalate Cd increased in roots and leaves,with a higher increase in oxalate Cd.Therefore,it is likely that root retention mechanisms,cell wall deposition,vacuole sequestration,and the formation of low mobility and low toxicity forms are tolerance strategies for Cd detoxification used by P.grandiflorum.The results of this study provide a theoretical grounding for the study of Cd accumulation and detoxification mechanisms in P.grandiflorum,and they can be used as a reference for developing Cd limits and standards for other medicine food homology plants. 展开更多
关键词 CADMIUM Platycodon grandiflorum inductively coupled plasma-mass-spectrometry subcellular distribution chemical forms heavy metal tolerance medicine food homology
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Histological Assessment of Bone Regeneration in the Maxilla with Homologous Bone Graft:A Feasible Option for Maxillary Bone Reconstruction
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作者 Sergio Henrique Gonçalves Motta Ana Paula Ramos Soares +1 位作者 Juliana Campos Hasse Fernandes Gustavo Vicentis Oliveira Fernandes 《Journal of Renewable Materials》 EI CAS 2024年第1期131-148,共18页
Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilize... Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilized)graft and verify its reliability.Eight individuals were included from 2014 to 2018.The first surgery was performed to install homologous bone blocks in the maxilla.The period of the second intervention varied between 5 months and 15 days to 11 months(≈7.93 months).The biopsies were taken from the central region of the matured graft during the surgery for implant placement.All patients presented clinical and radiographic conditions for the installation of dental implants.There was a 100%of survival rate.The histological assessment showed that the homologous block bone graft was an osteoconductive biomaterial,with connective tissue present,and newly formed bone juxtaposed on its surface.There were bone trabeculae with osteocytes and active osteoblasts with connective tissue in the mineralization process;the remodeling process can be found through the reverse lines.A limited focus of necrosis with fibrosis was detected,with small resorption and areas of inflammatory infiltrate,but without clinical significance.The homologous block bone graft can be considered a feasible option to substitute the autogenous bone graft(gold standard),with predictable clinical and favorable histological results.The patients had a shorter surgical period,low morbidity,and an unlimited amount of biomaterial available at an accessible cost. 展开更多
关键词 Regeneration bone graft HISTOLOGY homologOUS allogenous AUTOGENOUS
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B7 homolog 3 in pancreatic cancer
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作者 Dijana Perovic Marija Dusanovic Pjevic +5 位作者 Vladimir Perovic Milka Grk Milica Rasic Maja Milickovic Tanja Mijovic Petar Rasic 《World Journal of Gastroenterology》 SCIE CAS 2024年第31期3654-3667,共14页
Despite advances in cancer treatment,pancreatic cancer(PC)remains a disease with high mortality rates and poor survival outcomes.The B7 homolog 3(B7-H3)checkpoint molecule is overexpressed among many malignant tumors,... Despite advances in cancer treatment,pancreatic cancer(PC)remains a disease with high mortality rates and poor survival outcomes.The B7 homolog 3(B7-H3)checkpoint molecule is overexpressed among many malignant tumors,including PC,with low or absent expression in healthy tissues.By modulating various immunological and nonimmunological molecular mechanisms,B7-H3 may influence the progression of PC.However,the impact of B7-H3 on the survival of patients with PC remains a subject of debate.Still,most available scientific data recognize this molecule as a suppressive factor to antitumor immunity in PC.Furthermore,it has been demonstrated that B7-H3 stimulates the migration,invasion,and metastasis of PC cells,and enhances resistance to chemotherapy.In preclinical models of PC,B7-H3-targeting monoclonal antibodies have exerted profound antitumor effects by increasing natural killer cell-mediated antibodydependent cellular cytotoxicity and delivering radioisotopes and cytotoxic drugs to the tumor site.Finally,PC treatment with B7-H3-targeting antibody-drug conjugates and chimeric antigen receptor T cells is being tested in clinical studies.This review provides a comprehensive analysis of all PC-related studies in the context of B7-H3 and points to deficiencies in the current data that should be overcome by future research. 展开更多
关键词 B7 homolog 3 Pancreatic cancer PROGNOSIS Signaling pathways IMMUNOTHERAPY
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Polycystic Ovary Syndrome-Related Infertility Based on the Theory of“Liver and Kidney Homology”
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作者 Meng Dong Hongli Zhu 《Journal of Clinical and Nursing Research》 2023年第1期1-6,共6页
Polycystic ovary syndrome(PCOS)is an endocrine disorder caused by hypothalamic-pituitary-ovarian(HPO)axis dysfunction.In the field of gynecology and reproduction,PCOS has emerged as both a research hot spot and a chal... Polycystic ovary syndrome(PCOS)is an endocrine disorder caused by hypothalamic-pituitary-ovarian(HPO)axis dysfunction.In the field of gynecology and reproduction,PCOS has emerged as both a research hot spot and a challenging area of study.According to Chinese medicine,this disease is related to kidney deficiency,phlegm and dampness obstruction,blood stasis and interconnection,Chong pulse impassability,the lack of Ren pulse,and the loss of uterine nourishment,all of which affect the normal development and maturation of eggs as well as the duration at which menstrual blood stores.In this paper,based on the theoretical basis of“liver collects blood,regulates the flow of qi,and is the master of drainage,”we explore the rationality of the treatment of this disease from the perspective of“liver and kidney have the same origin”and the development of PCOS-related infertility in relation to dysfunctional internal organs.We also explore the feasibility of treatment from the perspective of“liver and kidney homology,”expand the ideas for treatment,as well as develop and innovate the application of organ identification in PCOS in relation to infertility. 展开更多
关键词 Polycystic ovary syndrome INFERTILITY Liver and kidney homology Dialectical treatment
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Clinical and molecular significance of homologous recombination deficiency positive non-small cell lung cancer in Chinese population:An integrated genomic and transcriptional analysis
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作者 Yifei Wang Yidan Ma +14 位作者 Lei He Jun Du Xiaoguang Li Peng Jiao Xiaonan Wu Xiaomao Xu Wei Zhou Li Yang Jing Di Changbin Zhu Liming Xu Tianlin Sun Lin Li Dongge Liu Zheng Wang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第3期282-297,共16页
Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not ... Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not been fully investigated.This study aimed to systematically analyze the HRD status of untreated NSCLC and its relationship with patient prognosis to further guide clinical care.Methods:A total of 355 treatment-naïve NSCLC patients were retrospectively enrolled.HRD status was assessed using the AmoyDx Genomic Scar Score(GSS),with a score of≥50 considered HRD-positive.Genomic,transcriptomic,tumor microenvironmental characteristics and prognosis between HRD-positive and HRDnegative patients were analyzed.Results:Of the patients,25.1%(89/355)were HRD-positive.Compared to HRD-negative patients,HRDpositive patients had more somatic pathogenic homologous recombination repair(HRR)mutations,higher tumor mutation burden(TMB)(P<0.001),and fewer driver gene mutations(P<0.001).Furthermore,HRD-positive NSCLC had more amplifications in PI3K pathway and cell cycle genes,MET and MYC in epidermal growth factor receptor(EGFR)/anaplastic lymphoma kinase(ALK)mutant NSCLC,and more PIK3CA and AURKA in EGFR/ALK wild-type NSCLC.HRD-positive NSCLC displayed higher tumor proliferation and immunosuppression activity.HRD-negative NSCLC showed activated signatures of major histocompatibility complex(MHC)-II,interferon(IFN)-γand effector memory CD8+T cells.HRD-positive patients had a worse prognosis and shorter progressionfree survival(PFS)to targeted therapy(first-and third-generation EGFR-TKIs)(P=0.042).Additionally,HRDpositive,EGFR/ALK wild-type patients showed a numerically lower response to platinum-free immunotherapy regimens.Conclusions:Unique genomic and transcriptional characteristics were found in HRD-positive NSCLC.Poor prognosis and poor response to EGFR-TKIs and immunotherapy were observed in HRD-positive NSCLC.This study highlights potential actionable alterations in HRD-positive NSCLC,suggesting possible combinational therapeutic strategies for these patients. 展开更多
关键词 Non-small cell lung cancer homologous recombination deficiency genetic alterations transcriptional analysis tumor microenvironment PROGNOSIS
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Low testing rates and high BRCA prevalence: Poly (ADP-ribose) polymerase inhibitor use in Middle East BRCA/homologous recombination deficiency-positive cancer patients
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作者 Naveed Syed Ashish Vittalrao Chintakuntlawar +6 位作者 Deepti Vilasini Aisha Mohamed Al Salami Riad Al Hasan Imrana Afrooz Kanishka Uttam Chandani Ashok Uttam Chandani Aref Chehal 《World Journal of Clinical Oncology》 2024年第7期848-858,共11页
BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breas... BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer.They are also effective for new and recurrent ovarian cancers that are BRCA-or homologous recombination deficiency(HRD)-positive.However,data on these mutations and PARPi use in the Middle East are limited.AIM To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.METHODS This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations,and 25 of 65 ovarian cancer patients tested for HRD.These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023.Data were summarized using descriptive statistics and compared using counts and percentages.Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.RESULTS Among the 472 breast cancer patients,12.1%underwent BRCA testing,and 38.5%of 65 ovarian cancer patients received HRD testing.Pathogenic mutations were found in 25.6%of the tested patients:26.3%breast cancers had germline BRCA(gBRCA)mutations and 24.0%ovarian cancers showed HRD.Notably,40.0%of gBRCA-positive breast cancers and 66.0%of HRD-positive ovarian cancers were Middle Eastern and Asian patients,respectively.PARPi treatment was used in 5(33.3%)gBRCA-positive breast cancer patients as first-line therapy(n=1;7-months progression-free),for maintenance(n=2;>15-months progression-free),or at later stages due to compliance issues(n=2).Four patients(66.6%)with HRD-positive ovarian cancer received PARPi and all remained progression-free.CONCLUSION Lower testing rates but higher BRCA mutations in breast cancer were found.Ethnicity reflected United Arab Emirates demographics,with breast cancer in Middle Eastern and ovarian cancer in Asian patients. 展开更多
关键词 homologous recombination repair BRCA1 BRCA2 homologous recombination deficiency Ovarian cancer Breast cancer Poly(ADP-ribose)polymerase inhibitors OLAPARIB DNA double-strand breaks
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Mitochondrial carrier homolog 2 increases malignant phenotype of human gastric epithelial cells and promotes proliferation,invasion,and migration of gastric cancer cells
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作者 Jing-Wen Zhang Ling-Yan Huang +3 位作者 Ya-Ning Li Ying Tian Jia Yu Xiao-Fei Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期991-1005,共15页
BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determi... BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determine the role of MTCH2 in gastric cancer.METHODS We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)cells.The mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial function.Mitochondrial function and ATP synthase protein levels were detected via Western blotting.RESULTS The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent tissues.Overexpression of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting apoptosis.CONCLUSION MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells. 展开更多
关键词 Gastric cancer Mitochondrial carrier homolog 2 ATP synthase ATP2A2 Mitochondrial permeability transformation pore
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The Report of Homological Algebra
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作者 Junhui Zhang 《Open Journal of Applied Sciences》 2024年第9期2749-2767,共19页
The current article intends to introduce the reader to the concept of injective and projective modules and to describe the CFT. We present a clear view to show the homological algebra and injective and projective modu... The current article intends to introduce the reader to the concept of injective and projective modules and to describe the CFT. We present a clear view to show the homological algebra and injective and projective modules. 展开更多
关键词 homological Algebra CATEGORY Projective and Injective Module
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Bioinformatics Analysis and Homology Modeling Study of Protein Disulfide Isomerase(mPDI) from Medicago sativa L. 被引量:3
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作者 王海波 施晓东 +1 位作者 张梅芬 郭俊云 《Agricultural Science & Technology》 CAS 2009年第5期59-64,共6页
pdi gene from Medicago sativa L. ,encoding Protein Disulfide Isomerase( mPDI ), has been cloned and sequenced. According to the mRNA and amino acid sequence, the character of mPDI such as the physical and chemical p... pdi gene from Medicago sativa L. ,encoding Protein Disulfide Isomerase( mPDI ), has been cloned and sequenced. According to the mRNA and amino acid sequence, the character of mPDI such as the physical and chemical properties, hydrophilicity/hydrophobicity, signal peptide, secondary structure, coiled coil, transmembrane domains, O-glycogylation site, active site, subcellular localization, functional structural domains and three-dimensional structure were analyzed by a series of bioinformatics software. The results showed that mPDI was a hydrophobic and stable protein with 3 coiled coils, 30-glycogylation sites, 2 structural domains of thioredoxin, 2 active sites of thioredoxin, and located in rough endoplasmic reticulum. It has 512 amino acids, the theoretical pl is 4.98, and signal peptide located in 1-24AA. In the secondary structure, a-helix, random coil, extended chain is 26.37%, 53.32%, 20.31% respectively. The validation of modeling accords with the stereochemistry. 展开更多
关键词 Medicago sativa L. Protein disulfide isomerase homology modeling
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Modeling Rice rgMT as a Plant Metallothionein-Like Protein by the Distance Geometry and Homology Methods
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作者 吕暾 刘进元 +1 位作者 张日清 赵南明 《Acta Botanica Sinica》 CSCD 2003年第11期1297-1306,共10页
Rice metallothionein-like protein (rgMT) shows characteristics of a three-section pattern composed of two highly conserved cysteine rich (CR) domains in the terminals and a spacer without cysteine (cys) residues in th... Rice metallothionein-like protein (rgMT) shows characteristics of a three-section pattern composed of two highly conserved cysteine rich (CR) domains in the terminals and a spacer without cysteine (cys) residues in the center of the molecule. In this paper, the two CR domains and the spacer region were modeled by the distance geometry and homology methods separately. For the CR domains, twenty random models were generated for each cys combination based on the constraint conditions of CXC (C represents cys, X represents any amino acid other than cys), and CXXC motifs and a metal-sulfur chelating cluster. Four models for the N-terminal and two for C-terminal CR domain containing metal chelating structures formed by different combinations of cys were selected from 900 possible conformations. The GOR method was used to predict the secondary structure of the spacer region and its model was built by the homology method. After three parts of the protein were modeled, they were connected to form a three-dimensional structure model of rgMT. The whole conformation showed that rgMT could form two independent metal-sulfur chelating structures connected by a spacer peptide, without a structural or energy barrier for them to form two independent metal-chelating clusters just as mammalian metallothionein (MT) proteins. As all plant metallothionein-like (MT-L) proteins have the same primary structural characteristic, two CR domains connected by a spacer region, and many have the same cys arrangement pattern as rgMT, the three-dimensional structure model of rgMT will provide an important reference for the structural study of other plant MT-L proteins. 展开更多
关键词 distance geometry homology method rice metallothionein-like protein structural modeling
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Use Chou’s 5-Steps Rule to Predict Remote Homology Proteins by Merging Grey Incidence Analysis and Domain Similarity Analysis 被引量:15
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作者 Weizhong Lin Xuan Xiao +1 位作者 Wangren Qiu Kuo-Chen Chou 《Natural Science》 2020年第3期181-198,共18页
Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the exi... Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the existing methods were trained and tested contain many high homologous samples as reflected by the fact that the cutoff threshold was set at 95%. In this study, we reconstructed the benchmark dataset by setting the threshold at 40%, meaning none of the proteins included in the benchmark dataset has more than 40% pairwise sequence identity with any other in the same subset. Using the new benchmark dataset, we proposed a new predictor called “dRHP-GreyFun” based on the grey modeling and functional domain approach. Rigorous cross-validations have indicated that the new predictor is superior to its counterparts in both enhancing success rates and reducing computational cost. The predictor can be downloaded from https://github.com/jcilwz/dRHP-GreyFun. 展开更多
关键词 REMOTE homology PROTEINS Grey Model DOMAIN Similarity Chou’s 5-Steps Rules
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Rodent epididymal cDNAs identified by sequence homology to human and canine counterparts 被引量:4
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作者 Katrin Kppler-Hanno Christiane Kirchhoff 《Asian Journal of Andrology》 SCIE CAS CSCD 2003年第4期277-286,共10页
<abstract>Aim: Identification of the rodent counterparts of human and canine epididymal cDNAs HE3, HE4 and Ce8/Ly6G5C by sequence homology and analysis of their expression patterns and regulation level in the ra... <abstract>Aim: Identification of the rodent counterparts of human and canine epididymal cDNAs HE3, HE4 and Ce8/Ly6G5C by sequence homology and analysis of their expression patterns and regulation level in the rat. Methods: 'Electronic screening' of Expressed Sequence Tag (EST) and genomic databases, followed by RT-PCR and Northern blot analysis. Results: Rodent ESTs and genomic sequences homologous to HE3, HE4 and Ce8/Ly6G5C were identified in the public databases and the 'full-length' rat cDNAs cloned. To emphasise their homology to the human and canine genes, they were named Me3/Re3, Me4/Re4 and Re8 for mouse and rat counterparts, respectively. mRNA expression patterns were analysed in rats, including rat HEl and HE5/CD52 counterparts as controls. Re3 and Re8 mRNAs were only found in the rat epididymis, while Re4 showed a broader tissue distribution. Within the epididymis, Re3 and Re4 mRNAs were detected in all regions; Re8, on the other hand, was restricted to the caput. During postnatal development, Re3 and control mRNAs were found from the earliest stages investigated, while Re8 mRNA was observed only from day 24 postnatum, corresponding to the onset of spermatogenesis in the prepubertal testis. Castration and testosterone supplementation of adult male rats suggested that none of the cloned mRNAs was directly androgen-regulated. Efferent duct ligation, however, showed that Re8 mRNA levels depended on testicular factors other than androgens. Conclusion: The novel rodent cDNAs can now be used to monitor epididymal gene expression more closely and to set up various regulatory and functional studies. 展开更多
关键词 EPIDIDYMIS cDNA homology cloning HE3- HE4- and Ce8-homologous proteins
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Homology Modeling of Mosquitocidal Cry30Ca2 of Bacillus thuringiensis and Its Molecular Docking with N-acetylgalactosamine 被引量:2
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作者 ZHAO Xin Min ZHOU Pan Deng XIA Li Qui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第5期590-596,共7页
Abstract Objective To investigate the theoretical model of the three-dimensional structure of mosquitocida Cry3OCa2 and its molecular docking with N-acetylgalactosamine. Methods The theoretical model of Cry30Ca2 was t... Abstract Objective To investigate the theoretical model of the three-dimensional structure of mosquitocida Cry3OCa2 and its molecular docking with N-acetylgalactosamine. Methods The theoretical model of Cry30Ca2 was the Cry4Ba. Docking studies were performed N-acetylgalactosamine on the putative receptor. predicted by homology modeling on the structure of to investigate the interaction of Cry3OCa2 with Results Cry3OCa2 toxin is a rather compact molecule composed of three distinct domains and has approximate overall dimensions of 95 by 75 by 60A. Domain I is a helix bundle, Domain Ⅱ consists of three antiparallel β-sheets, Domain Ⅲ is composed of two β-sheets that adopt a 13-sandwich fold. Residue 32111e in loop1, residues 342Gin 343Thr and 345Gin in loop2, residue 393Tyr in loop3 of Cry3OCa2 are responsible for the interactions with GalNAc via 7 hydrogen bonds, 6 of them were related to the oxygen atoms of hydroxyls of the ligand, and one to the nitrogen of the ligand. Conclusion The 3D structure of Cry3OCa2 resembles the previously reported Cry toxin structures but shows still some distinctions. Several residues in the loops of the apex of domain Ⅱ are responsible for the interactions with N-acetylgalactosamine. 展开更多
关键词 Cry3OCa2 Bacillus thuringiensis homology modeling MOSQUITOES Molecular docking
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Expression,Purification,Characteristics and Homology Modeling of the HMGS from Streptococcus pneumoniae 被引量:1
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作者 YA-LI BEN GU-ZHEN CUI +5 位作者 CHEN LI RUI HAN JIE ZHANG QING-YE ZHANG JIAN WAN DE-LI LIU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第3期229-236,共8页
Objective To understand the molecular basis for a potential reaction mechanism and develop novel antibiotics with homology modeling for 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase (HMGS). Methods The ... Objective To understand the molecular basis for a potential reaction mechanism and develop novel antibiotics with homology modeling for 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase (HMGS). Methods The genetic engineering technology and the composer module of SYBYL7.0 program were used, while the HMGS three-dimensional structure was analyzed by homology modeling. Results The mvaS gene was cloned from Streptococcus pneumoniae and overexpressed in Escherichia coli from a pET28 vector. The expressed enzyme (about 46 kDa) was purified by affinity chromatography with a specific activity of 3.24 μmol/min/mg. Optimal conditions were pH 9.75 and 10 mmol/L MgCl2 at 37 ℃ The Vmax and Km were 4.69 μmol/min/mg and 213 μmol/L respectively. The 3D model of S.pneumoniae HMGS was established based on structure template of HMGS of Enterococcus faecalis. Conelusion The structure of HMGS will facilitate the structure-based design of alternative drugs to cholesterol-lowering therapies or to novel antibiotics to the Gram-positive cocci, whereas the recombinant HMGS will prove useful for drug development against a different enzyme in the mevalonate pathway. 展开更多
关键词 Streptococcus pneumoniae HMG-CoA synthase Analysis of dynamics homology modeling
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Cloning and Homology Comparison of S Gene for Isolate TH-98 of Porcine Transmissible Gastroenteritis Virus 被引量:1
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作者 RENXiao-feng LIYi-jing 《Agricultural Sciences in China》 CAS CSCD 2003年第3期314-320,共7页
TH-98 isolate of transmissible gastroenteritis virus (TGEV) was propagated and harvested on swine testicle (ST) monolayer cell. Two pairs of primers were designed to amplify S gene by RT-PCR according to the published... TH-98 isolate of transmissible gastroenteritis virus (TGEV) was propagated and harvested on swine testicle (ST) monolayer cell. Two pairs of primers were designed to amplify S gene by RT-PCR according to the published sequence of TGEV'S gene cDNA with Oligo version 4.1 and DNasis software. The products of PCR were named Sa and Sb, of 2.3 kb and 2.1 kb respectively. Sa was inserted in EcoR I and Kpn I sites after Sb was cloned in Kpn I and Pst I multiple cloning sites of the same pUC18 plasmid. The recombinant pUC-S plasmid was identified and analyzed by corresponding restriction endonuclease and nested PCR on the basis of the genetic sites of S gene and pUC18 plasmid, which was identified as S gene of TGEV. Recombinant pUC-S was sequenced and analyzed in comparison with the other strains. Gene sequence comparison indicated that TH-98 shared 99, 97, 98, 97 and 94% identities with Purdue-115(US), Miller(US), TO14(Japan), FS772(British), 96-1933(British), respectively, their deduced amino acid homology was 99, 97, 97, 96 and 93% correspondingly. In addition, the analysis report verified that pUC-S owned a complete open reading frame (ORF) including initiation codon, signal sequences, remaining sequences and termination codon as well. Therefore, the results affirmed that S gene of TGEV TH-98 was extremely conservative. 展开更多
关键词 Transmissible gastroenteritis virus S gene CLONING homology Comparison
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AN ANALOGUE OF KüNNETH THEOREM INSTRONG HOMOLOGY 被引量:1
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作者 Dae- Woong Lee 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期32-40,共9页
After defining the strong tensor product of strong (sub)chain complenes, it is shown that an analogue of the Kunneth theorem holds in strong homology by proving that the kernel (cokernel) of connecting homomorphisms i... After defining the strong tensor product of strong (sub)chain complenes, it is shown that an analogue of the Kunneth theorem holds in strong homology by proving that the kernel (cokernel) of connecting homomorphisms is isomorphic to the direct sum of torsion (tensor) products of strong homology groups. An isomorphism between strong (r-stage) homology groups of inverse systems is also constructed. 展开更多
关键词 Derived limit strong (r-stage) homology strong tensor product Mittag-Leffler property
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Homology Modelling and Structural Comparisons of Capsid-Associated Proteins from Circoviruses Reveal Important Virus-Specific Surface Antigens 被引量:1
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作者 Edward I. Patterson Jade K. Forwood Shane R. Raidal 《Crystal Structure Theory and Applications》 2012年第2期9-16,共8页
Circoviridae represent a growing family of small animal viruses. Some of these viruses have veterinary and medical importance, although, a vast amount of these newly discovered viruses have unknown effects on their ho... Circoviridae represent a growing family of small animal viruses. Some of these viruses have veterinary and medical importance, although, a vast amount of these newly discovered viruses have unknown effects on their hosts. The capsid-associated protein (Cap) of circoviruses is of interest because of its role in viral structure, immune evasion, host cell entry, and nuclear shuttling of viral components. The structure of the porcine circovirus 2 (PCV2) Cap has been solved and offered insight to these functions. Based on the crystallographic PCV2 Cap structure, models from circoviruses isolated from avian, fish, and mammalian hosts have been constructed and analyzed to better understand the roles of these proteins in the virus family. A high degree of conservation is observed in the models, however, the surface antigens differ among viruses. This is likely a reflection of the small genome harbored by circoviruses, and therefore the requirement of their few proteins to carry out specific vital functions, while maintaining enough variation to successfully infect their hosts. Here we describe the putative structures of a range of Cap proteins from circoviruses based on the crystallographic determination of porcine Cap, identifying key regions for function and inhibition of crystal formation. 展开更多
关键词 CIRCOVIRUS Capsid-Associated Protein Structure homology CAP Modelling
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Indonesian avian influenza H274Y mutant neuraminidase homology models assessment 被引量:1
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作者 Sigit Jaya Herlambang Rosari Saleh 《Journal of Biophysical Chemistry》 2011年第3期345-352,共8页
Five models of Indonesian H274Y mutant neuralminidase type 1 (N1) were generated from the template 3CKZ by homology modeling. The template has the best similarity percentage 97% with the model sequence. The models was... Five models of Indonesian H274Y mutant neuralminidase type 1 (N1) were generated from the template 3CKZ by homology modeling. The template has the best similarity percentage 97% with the model sequence. The models was evaluated to search the best model with DOPE, 3D-profiles and PROCHECK in a good rank. The results show model 3 as a potential model to be used in the simulation with the lowest DOPE score, highest verify-3D score and from Ramachandran plots we inferred that it also shared the 1st rank with model 4 based on the 99.4% of the residues found, without Glycine and Proline, at the most favoured and additionally allowed region of both model structures. 展开更多
关键词 NEURAMINIDASE MODEL Assessment homology MODEL MUTANT AVIAN Influenza
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Homology modeling and evolutionary trace analysis of superoxide dismutase from extremophile Acidithiobacillus ferrooxidans 被引量:1
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作者 刘元东 王海东 邱冠周 《Journal of Central South University of Technology》 EI 2007年第5期612-617,共6页
The gene sod in Acidithiobacillusferrooxidans may play a crucial role in its tolerance to the extremely acidic, toxic and oxidative environment of bioleaching. For insight into the anti-toxic mechanism of the bacteria... The gene sod in Acidithiobacillusferrooxidans may play a crucial role in its tolerance to the extremely acidic, toxic and oxidative environment of bioleaching. For insight into the anti-toxic mechanism of the bacteria, a three-dimensional (3D) molecular structure of the protein encoded by this gene was built by homology modeling techniques, refined by molecular dynamics simulations, assessed by PROFILE-3D and PROSTAT programs and its key residues were further detected by evolutionary trace analysis. Through these procedures, some trace residues were identified and spatially clustered. Among them, the residues of Asn38, Glyl03 and Glul61 are randomly scattered throughout the mapped structure; interestingly, the other residues are all distinctly clustered in a subgroup near Fe atom. From these results, this gene can be confirmed at 3D level to encode the Fe-depending superoxide dismutase and subsequently play an anti-toxic role. Furthermore, the detected key residues around Fe binding site can be conjectured to be directly responsible for Fe binding and catalytic function. 展开更多
关键词 BIOLEACHING superoxide dismutase Acidithiobacillus ferrooxidans homology modeling evolutionary trace molecular dynamics
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