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
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
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
Let A be a tame Hecke algebra of type A. A new minimal projective bimodule resolution for A is constructed and the dimensions of all the Hochschild homology groups and cyclic homology groups are calculated explicitly.
In this paper, we propose a new algorithm to compute the homology of a finitely generated chain complex. Our method is based on grouping several reductions into structures that can be encoded as directed acyclic graph...In this paper, we propose a new algorithm to compute the homology of a finitely generated chain complex. Our method is based on grouping several reductions into structures that can be encoded as directed acyclic graphs. The organized reduction pairs lead to sequences of projection maps that reduce the number of generators while preserving the homology groups of the original chain complex. This sequencing of reduction pairs allows updating the boundary information in a single step for a whole set of reductions, which shows impressive gains in computational performance compared to existing methods. In addition, our method gives the homology generators for a small additional cost.展开更多
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
<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
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
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
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
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
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
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
Osteoporosis is a systemic chronic metabolic bone disease,mainly in the elderly and postmenopausal women.At present,most of the clinical treatment is western medicine,but the curative effect is not very significant.In...Osteoporosis is a systemic chronic metabolic bone disease,mainly in the elderly and postmenopausal women.At present,most of the clinical treatment is western medicine,but the curative effect is not very significant.In the treatment of osteoporosis,traditional Chinese medicine(TCM)is mainly based on the overall concept of TCM.This article briefly analyzes osteoporosis from the theory of"liver and kidney homology,"discusses the research on osteoporosis in TCM,and hopes to provide reference for the clinical treatment and research of osteoporosis.展开更多
μC/OS-Ⅱ is an open source real-time kernel adopting priority preemptive schedule strategy. Aiming at the problem of μC/OS-Ⅱ failing to support homology priority tasks scheduling, an approach for solution is propos...μC/OS-Ⅱ is an open source real-time kernel adopting priority preemptive schedule strategy. Aiming at the problem of μC/OS-Ⅱ failing to support homology priority tasks scheduling, an approach for solution is proposed. The basic idea is adding round-robin scheduling strategy in its original scheduler in order to schedule homology priority tasks through time slice roundrobin. Implementation approach is given in detail. Firstly, the Task Control Block (TCB) is extended. And then, a new priority index table is created, in which each index pointer points to a set of homology priority tasks. Eventually, on the basis of reconstructing μC/OS-Ⅱ real-time kernel, task scheduling module is rewritten. Otherwise, schedulability of homology task supported by modified kernel had been analyzed, and deadline formula of created homology tasks is given. By theoretical analysis and experiment verification, the modified kernel can support homology priority tasks scheduling, meanwhile, it also remains preemptive property of original μC/OS-Ⅱ.展开更多
We introduce a homology-based recombination approach for generating a cDNA construct. This method depends on amplifying several exon fragments and their fusions by the homology-based recombination. This method provide...We introduce a homology-based recombination approach for generating a cDNA construct. This method depends on amplifying several exon fragments and their fusions by the homology-based recombination. This method provides a way to generate the cDNA sequence of any gene without any need for its mRNA. The paper describes the strategy by assembling cDNA of the MYB1 and MYB2 genes of Arabidopsis thaliana.展开更多
The purpose of this paper is to define Hochschild type homology of Bihomassociative algebras and Chevalley-Eilenberg type homology of Bihom-Lie algebras with non-trivial coefficients in their bimodules respectively.In...The purpose of this paper is to define Hochschild type homology of Bihomassociative algebras and Chevalley-Eilenberg type homology of Bihom-Lie algebras with non-trivial coefficients in their bimodules respectively.In particular,we give their low order homology in detail.展开更多
A homological analogue of curve complex of a closed connected orientable surface is developed and studied. The dis-tance in this complex is shown to be quite computable and an algorithm given (Theorem 3.5). As an appl...A homological analogue of curve complex of a closed connected orientable surface is developed and studied. The dis-tance in this complex is shown to be quite computable and an algorithm given (Theorem 3.5). As an application of this complex it is shown that for a closed orientable 3-manifold, and any of its Heegaard splittings, one can give an algorithm to decide whether the manifold contains a 2-sided, non-separating, closed incompressible surface (Theorem 1.1).展开更多
The base sequence in genome was governed by some fundamental principles such as reverse-complement symmetry, multiple fractality and so on, and the analytical method of the genome structure, the “Sequence Spectrum Me...The base sequence in genome was governed by some fundamental principles such as reverse-complement symmetry, multiple fractality and so on, and the analytical method of the genome structure, the “Sequence Spectrum Method (SSM)”, based on the structural features of genomic DNA faithfully visualized these principles. This paper reported that the sequence spectrum in SSM closely reflected the biological phenomena of protein and DNA, and SSM could identify the interactive region of protein-protein and DNA-protein uniformly. In order to investigate the effectiveness of SSM we analyzed the several protein-protein and DNA-protein interaction published primarily in the genome of Saccharomyces cerevisiae. The method proposed here was based on the homology of sequence spectrum, and it advantageously and surprisingly used only base sequence of genome and did not require any other information, even information about the amino-acid sequence of protein. Eventually it was concluded that the fundamental principles in genome governed not only the static base sequence but also the dynamic function of protein and DNA.展开更多
基金This work was supported by the Major Science and Technology Projects in Inner Mongolia Autonomous Region(No.2019ZD005)the National Natural Science Foundation of China(No.81903751)+1 种基金by the Natural Science Basic Research Project of Shaanxi Science and Technology Department(No.2019JQ-877)by the Scientific Research Project of Shaanxi Administration of Traditional Chinese Medicine(No.2019-ZZ-ZY018).
文摘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.
文摘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.
基金This study is carried out by Cukurova University Scientific Research Projects(BAP)is supported with Project No:FDK-2019-11621.
文摘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.
文摘Let A be a tame Hecke algebra of type A. A new minimal projective bimodule resolution for A is constructed and the dimensions of all the Hochschild homology groups and cyclic homology groups are calculated explicitly.
文摘In this paper, we propose a new algorithm to compute the homology of a finitely generated chain complex. Our method is based on grouping several reductions into structures that can be encoded as directed acyclic graphs. The organized reduction pairs lead to sequences of projection maps that reduce the number of generators while preserving the homology groups of the original chain complex. This sequencing of reduction pairs allows updating the boundary information in a single step for a whole set of reductions, which shows impressive gains in computational performance compared to existing methods. In addition, our method gives the homology generators for a small additional cost.
文摘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.
文摘<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.
基金supported by grants from Hunan Provincial Natural Science Foundation of China(No.12JJ3021)the National Natural Science Foundation of China(No.30670052,30570050)863 Program of China(2006AA02Z187)
文摘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.
基金supported by the National Natural Science Foundation of China (No. 30771429)Science and Technology Research Project of Ministry of Education (No.106116)+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education (No. 20060511002)the Natural Science Foundation of Hubei Province (No. 2006ABA197)
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
文摘Osteoporosis is a systemic chronic metabolic bone disease,mainly in the elderly and postmenopausal women.At present,most of the clinical treatment is western medicine,but the curative effect is not very significant.In the treatment of osteoporosis,traditional Chinese medicine(TCM)is mainly based on the overall concept of TCM.This article briefly analyzes osteoporosis from the theory of"liver and kidney homology,"discusses the research on osteoporosis in TCM,and hopes to provide reference for the clinical treatment and research of osteoporosis.
基金Supported by the "Chunhui" Plan of Ministry of Education of China (Z2005-2-11013)
文摘μC/OS-Ⅱ is an open source real-time kernel adopting priority preemptive schedule strategy. Aiming at the problem of μC/OS-Ⅱ failing to support homology priority tasks scheduling, an approach for solution is proposed. The basic idea is adding round-robin scheduling strategy in its original scheduler in order to schedule homology priority tasks through time slice roundrobin. Implementation approach is given in detail. Firstly, the Task Control Block (TCB) is extended. And then, a new priority index table is created, in which each index pointer points to a set of homology priority tasks. Eventually, on the basis of reconstructing μC/OS-Ⅱ real-time kernel, task scheduling module is rewritten. Otherwise, schedulability of homology task supported by modified kernel had been analyzed, and deadline formula of created homology tasks is given. By theoretical analysis and experiment verification, the modified kernel can support homology priority tasks scheduling, meanwhile, it also remains preemptive property of original μC/OS-Ⅱ.
文摘We introduce a homology-based recombination approach for generating a cDNA construct. This method depends on amplifying several exon fragments and their fusions by the homology-based recombination. This method provides a way to generate the cDNA sequence of any gene without any need for its mRNA. The paper describes the strategy by assembling cDNA of the MYB1 and MYB2 genes of Arabidopsis thaliana.
基金Supported by the National Science Foundation of China(Grant Nos.11047030,11171055).
文摘The purpose of this paper is to define Hochschild type homology of Bihomassociative algebras and Chevalley-Eilenberg type homology of Bihom-Lie algebras with non-trivial coefficients in their bimodules respectively.In particular,we give their low order homology in detail.
文摘A homological analogue of curve complex of a closed connected orientable surface is developed and studied. The dis-tance in this complex is shown to be quite computable and an algorithm given (Theorem 3.5). As an application of this complex it is shown that for a closed orientable 3-manifold, and any of its Heegaard splittings, one can give an algorithm to decide whether the manifold contains a 2-sided, non-separating, closed incompressible surface (Theorem 1.1).
文摘The base sequence in genome was governed by some fundamental principles such as reverse-complement symmetry, multiple fractality and so on, and the analytical method of the genome structure, the “Sequence Spectrum Method (SSM)”, based on the structural features of genomic DNA faithfully visualized these principles. This paper reported that the sequence spectrum in SSM closely reflected the biological phenomena of protein and DNA, and SSM could identify the interactive region of protein-protein and DNA-protein uniformly. In order to investigate the effectiveness of SSM we analyzed the several protein-protein and DNA-protein interaction published primarily in the genome of Saccharomyces cerevisiae. The method proposed here was based on the homology of sequence spectrum, and it advantageously and surprisingly used only base sequence of genome and did not require any other information, even information about the amino-acid sequence of protein. Eventually it was concluded that the fundamental principles in genome governed not only the static base sequence but also the dynamic function of protein and DNA.