Carrying the roots of Chinese civilization to its origins,the Chinese Primer classic has received considerable attention in the international community’s cultural diffusion.The spread of the Chinese Primer class stud...Carrying the roots of Chinese civilization to its origins,the Chinese Primer classic has received considerable attention in the international community’s cultural diffusion.The spread of the Chinese Primer class studies in the United States,aided by missionaries such as E.C.Bridgeman,Samuel Wells Williams,and William Alexander Parsons Martin,sinologists such as Witter Bynner and David Hinton,has been characterized by unidirectionality,permeability,and pluralism.展开更多
[Objective] The aim was to screen out simple methods of DNA extraction and effective ISSR primers suitable to all germplasm materials of Camellia chekiangoleosa.[Method] The modified CTAB method was used in the extrac...[Objective] The aim was to screen out simple methods of DNA extraction and effective ISSR primers suitable to all germplasm materials of Camellia chekiangoleosa.[Method] The modified CTAB method was used in the extraction of the genomic DNA,50 ISSR primers from other Camellia plants were used in the ISSR-PCR amplification for 20 germplasm materials from 10 populations in Fujian,Zhejiang,Jiangxi and Anhui Province.[Result] Pure DNA could be obtained rapidly by using the improved CTAB method,and the 20 selected effective primers had rich polymorphism,clear bands and good repeatability.337 DNA bands were obtained,of which 281 bands were polymorphic,accounting for 83.4% of the total amplified bands.And 16.85 bands could be amplified with a primer,averagely.[Conclusion] The selected 20 primers could be effectively applied to ISSR analysis of the germplasm resources of C.chekiangoleosa in Zhejiang.展开更多
[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus （AIV） ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 su...[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus （AIV） ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 subtypes of AIV accessed in GenBank, and design primers（ by Primer Premier 5.0） on high homologous region of these sequences, and then amplified by RT-PCR. [Result] The multiplex RT-PCR amplification, agarose gel electrophoresis and sequencing results showed that the self-designed primers are successful for detecting AIV. [Conclusion] It is feasible to rapidly diagnose AIV through this method.展开更多
[ Objective] To provide effective primers for the rapid and accurate ISSR analysis of the germplasm materials of Mallotus oblongiolus （Miq.） Muello-Arg.. [Method] The modified CTAB method was used in the extraction ...[ Objective] To provide effective primers for the rapid and accurate ISSR analysis of the germplasm materials of Mallotus oblongiolus （Miq.） Muello-Arg.. [Method] The modified CTAB method was used in the extraction of the genomic DNA. 99 ISSR primers were used in the ISSR-PCR amplification for 20 germplasm materials from 10 populations in Hainan Island, so that some primers, which were suitable to all gerplasm materials of M. oblongiolu, could be selected. [ Result] 15 effective primers with characteristics of rich polymorphism, clear bands, and good repeatability were selected from 99 test primers. The 15 primers selected were used in the ISSR-PCR amplification for 66 germplasm materials of M. oblongiolus. From all of which the abundant and distinct DNA fingerprintings could be obtained. 286 DNA bands were obtained, and of which 231 bands were polymorphic, which amounted to 80.77% of the total bands amplified. And 19.1 bands could be obtained with each primer, averagely. [ Conclusion] The 15 primers selected could be effectively applied to ISSR analysis of the germplasm resources of M. oblongiolus.展开更多
[Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper （Capsicum） hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Re...[Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper （Capsicum） hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Result] According to the polymorphism and heterozygosity, Hpms1-214, Es395 and Hpmsl-5 were determined as three preferred core primers for purity identification of pepper hybrids. By using these three preferred core primers, 97 pepper hybrids （accounting for 97%） had heterozygous band pattern with at least one primer. Es330, Es363, Epms923, Es120 and Es64 were determined as candidate core primers for purity identification of pepper hybrids. Specific primers of 14 varieties were obtained, which could be used to further screen parent-complementary primers of each pepper hybrid. [Con- clusion] This study laid the foundation for constructing standard DNA fingerprints for purity identification of pepper hybrids.展开更多
[Objective] The aim was to explore the special methods for amplification of large-family genes by using primers with high degeneracy.[Method] By using the primers with high degeneracy,conventional PCR,conventional tou...[Objective] The aim was to explore the special methods for amplification of large-family genes by using primers with high degeneracy.[Method] By using the primers with high degeneracy,conventional PCR,conventional touchdown PCR and the optimized abnormal touchdown PCR were respectively carried out to amplify the genomic DNA of Cyprinus carpio.[Result] Only one evident electrophoretic band and a few Sox genes were obtained by using normal PCR;no obvious electrophoretic band but dispersive product was obtained by normal touchdown PCR;ideal result was obtained by the abnormal touchdown PCR that three evident electrophoretic bands and much more Sox genes were amplified.[Conclusion] The research provided theoretical basis for the optimization and selection of PCR amplification conditions of the large-family genes.展开更多
[Objective] Grb-AST7 concatemer including 17 copies of Grb-AST7 was constructed by ＂self template-primer＂ PCR. [Method] Two primers of which were synthesized based on the amino acid sequence of Gryllus bimaculatus’...[Objective] Grb-AST7 concatemer including 17 copies of Grb-AST7 was constructed by ＂self template-primer＂ PCR. [Method] Two primers of which were synthesized based on the amino acid sequence of Gryllus bimaculatus’ Grb-AST7. [Result] Through splicing, a length of 570 bp, containing 17 copies of the Grb-AST7 gene repeats were obtained. Appropriate primer splicing conditions were as follows：splice time 20 min, 25 μl PCR system, containing 2 μl template. [Conclusion] The results laid foundation for the future studies on Grb-AST7 gene expression and bio-activity analysis.展开更多
[Objective] The aim was to explore the reasons of false positives in Different Display Reverse Transcription（DDRT）analysis.[Method] Soybean varieties ＂Jilin 30＂ and ＂Tongnong 13＂ were used as materials to carry ...[Objective] The aim was to explore the reasons of false positives in Different Display Reverse Transcription（DDRT）analysis.[Method] Soybean varieties ＂Jilin 30＂ and ＂Tongnong 13＂ were used as materials to carry out analysis on false positives in DDRT analysis.[Result] An important origin of false positives appeared in DDRT analysis was the non-specific amplification caused by the combination of single primer and cDNA.The parallel PCR test of single primer should be set so as to verify whether the obtained fragments were the false positives or the PCR productions combined with single primer.[Conclusion] This study had provided basis for improving the success rate of DDRT experiment.展开更多
[Objective] This research aimed to develop walnut EST-SSR markers and design corresponding primers.[Method] 5213 EST sequences of walnut（Juglans regia Linn.） public online in NCBI were used for character analysis wi...[Objective] This research aimed to develop walnut EST-SSR markers and design corresponding primers.[Method] 5213 EST sequences of walnut（Juglans regia Linn.） public online in NCBI were used for character analysis with bioinformatics methods,and primers were designed for the selected EST sequences by using Primer 3.0 software.[Result] 207 SSRs were obtained from the EST sequences,including 188 non-redundant sequences,the detection rate was 3.97% with an average distribution distance of 21.12 kb.Totally 92 types of repeat motifs were involved,which were mainly composed of dinucleotide and trinucleotide,accounting for 31.40% and 35.27% of the total number of repeat motifs,respectively.30 pairs of primers were initially selected from the 50 randomly-selected SSR primers by PCR amplification.[Conclusion] This research would lay foundations for the development of EST-SSR molecular markers in walnut and design of the targeted EST-SSR primers by mining and analyzing the SSR sites in walnut EST sequences.展开更多
At present,there are unharmonious factors existing in Chinese family education,which particular manifest in the means of family education.The Three Character Primer,as an epitome of the essence of Chinese traditional ...At present,there are unharmonious factors existing in Chinese family education,which particular manifest in the means of family education.The Three Character Primer,as an epitome of the essence of Chinese traditional culture,can provide enlightenment on building a democratic and harmonious family education means.展开更多
In an effort to simplify the procedure and to reduce the cost of fluorescence SSR analysis, the conditions of the multiplex PCR and the multiplex gel electrophoresis were optimized in the genetic analysis of sunflower...In an effort to simplify the procedure and to reduce the cost of fluorescence SSR analysis, the conditions of the multiplex PCR and the multiplex gel electrophoresis were optimized in the genetic analysis of sunflower (Helianthus annuus L.) inbred lines. Results indicated that factors for a successful multiplex PCR assay were related to the cycling touchdown annealing temperature, the balance of primer concentration at the various loci, the concentration of PCR buffer and the Taq DNA polymerase. Based on the optimization, a tailed primer strategy was outlined, and the effective ways were proposed to overcome the troubleshootings commonly encountered in the multiplex PCR and the multiplex gel electrophoresis.展开更多
AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using ...AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.展开更多
Among many reports investigating microbial diversity from environmental samples with denaturing gradient gel electrophoresis (DGGE), limited attention has been given to the effects of universal primers and DNA extract...Among many reports investigating microbial diversity from environmental samples with denaturing gradient gel electrophoresis (DGGE), limited attention has been given to the effects of universal primers and DNA extraction on the outcome of DGGE analysis. In this study, these effects were tested with 16S rRNA gene-based DGGE on a bacterial community from farming water samples. The results indicate that the number of discernable bands in the DGGE fingerprint differed with the primer pairs used; the bands produced by 63f/518r, 341f/926r and 933f/1387r primer pairs were obviously fewer than those by 968f/1401r. Also, we found that each DNA extraction method resulted in different community profiles, reflected by the number and intensity of bands in the DGGE fingerprint. Furthermore, the main bands (theoretically representing dominant bacteria) differed with the extraction methods applied. It is therefore believed that the effects of universal primers and DNA extraction should be given more attention and carefully chosen before performing an investigation into a new environment with DGGE.展开更多
There is an increasing requirement for traceability of aquaculture products, both for consumer protection and for food safety. There are high error rates in the conventional traceability systems depending on physical ...There is an increasing requirement for traceability of aquaculture products, both for consumer protection and for food safety. There are high error rates in the conventional traceability systems depending on physical labels. Genetic traceability technique depending on DNA-based tracking system can overcome this problem. Genealogy information is essential for genetic traceability, and microsatellite DNA marker is a good choice for pedigree analysis. As increasing genotyping throughput of microsatellites, microsatellite multiplex PCR has become a fast and cost-effective technique. As a commercially important cultured aquatic species, Pacific oyster Crassostrea gigas has the highest global production. The objective of this study was to develop microsatellite multiplex PCR panels with dye-labeled universal primer for pedigree analysis in C. gigas, and these multiplex PCRs were validated using 12 full-sib families with known pedigrees. Here we developed six informative multiplex PCRs using 18 genomic microsatellites in C. gigas. Each multiplex panel contained a single universal primer M13(-21) used as a tail on each locus-specific forward primer and a single universal primer M13(-21) labeled with fluorophores. The polymorphisms of the markers were moderate, with an average of 10.3 alleles per locus and average polymorphic information content of 0.740. The observed heterozygosity per locus ranged from 0.492 to 0.822. Cervus simulations revealed that the six panels would still be of great value when massive families were analysed. Pedigree analysis of real offspring demonstrated that 100% of the offspring were unambiguously allocated to their parents when two multiplex PCRs were used. The six sets of multiplex PCRs can be an important tool for tracing cultured individuals, population genetic analysis, and selective breeding program in C. gigas.展开更多
Tylenchulus semipenetrans is the most economically important and widespread nematode pest of citrus in China.rDNA-ITS of 14 populations of T.semipenetrans which were collected from different citrus groves or Chinese ...Tylenchulus semipenetrans is the most economically important and widespread nematode pest of citrus in China.rDNA-ITS of 14 populations of T.semipenetrans which were collected from different citrus groves or Chinese fir（Cunninghamia lanceolata） plantations in China were amplified and sequenced.The species-specific primers were designed for the first time to diagnosis T.semipenetrans based on the sequences of rDNA-ITS regions of geographic population above.The primers were sensitive to amplify the expected band size（297 bp） from DNA template of a single second-stage juvenile（J2） or different life stages of T.semipenetrans.No specific band was amplified from 15 non-target nematode species which were commonly found in citrus groves.Specificity and reliability of the primers were validated by further PCR amplification of 16 extra populations of T.semipenetrans collected from 4 provinces of China.The primers successfully detected a single J2 of T.semipenetrans within a whole nematode community comprising a large numbers of non-target nematode.The developed diagnostic technique can be used for accurate identification of T.semipenetrans and also as a decision tool for nematode management for citrus or Chinese fir in China.展开更多
基金The National Social Science Foundation of China(No.17AZS012)Jiangsu Province:“Postgraduate Research and Practice Innovation Program”(KYCX22__3585).
文摘Carrying the roots of Chinese civilization to its origins,the Chinese Primer classic has received considerable attention in the international community’s cultural diffusion.The spread of the Chinese Primer class studies in the United States,aided by missionaries such as E.C.Bridgeman,Samuel Wells Williams,and William Alexander Parsons Martin,sinologists such as Witter Bynner and David Hinton,has been characterized by unidirectionality,permeability,and pluralism.
基金Supported by Project of Zhejiang Provincial Department of Scienceand Technology(2010C32043)~~
文摘[Objective] The aim was to screen out simple methods of DNA extraction and effective ISSR primers suitable to all germplasm materials of Camellia chekiangoleosa.[Method] The modified CTAB method was used in the extraction of the genomic DNA,50 ISSR primers from other Camellia plants were used in the ISSR-PCR amplification for 20 germplasm materials from 10 populations in Fujian,Zhejiang,Jiangxi and Anhui Province.[Result] Pure DNA could be obtained rapidly by using the improved CTAB method,and the 20 selected effective primers had rich polymorphism,clear bands and good repeatability.337 DNA bands were obtained,of which 281 bands were polymorphic,accounting for 83.4% of the total amplified bands.And 16.85 bands could be amplified with a primer,averagely.[Conclusion] The selected 20 primers could be effectively applied to ISSR analysis of the germplasm resources of C.chekiangoleosa in Zhejiang.
基金Supported by Important Project of Jinlin Provincial Science and Technology Department(20065020)~~
文摘[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus （AIV） ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 subtypes of AIV accessed in GenBank, and design primers（ by Primer Premier 5.0） on high homologous region of these sequences, and then amplified by RT-PCR. [Result] The multiplex RT-PCR amplification, agarose gel electrophoresis and sequencing results showed that the self-designed primers are successful for detecting AIV. [Conclusion] It is feasible to rapidly diagnose AIV through this method.
基金Supported by Special Fund for Key Disciplines Program of HainanUniversity~~
文摘[ Objective] To provide effective primers for the rapid and accurate ISSR analysis of the germplasm materials of Mallotus oblongiolus （Miq.） Muello-Arg.. [Method] The modified CTAB method was used in the extraction of the genomic DNA. 99 ISSR primers were used in the ISSR-PCR amplification for 20 germplasm materials from 10 populations in Hainan Island, so that some primers, which were suitable to all gerplasm materials of M. oblongiolu, could be selected. [ Result] 15 effective primers with characteristics of rich polymorphism, clear bands, and good repeatability were selected from 99 test primers. The 15 primers selected were used in the ISSR-PCR amplification for 66 germplasm materials of M. oblongiolus. From all of which the abundant and distinct DNA fingerprintings could be obtained. 286 DNA bands were obtained, and of which 231 bands were polymorphic, which amounted to 80.77% of the total bands amplified. And 19.1 bands could be obtained with each primer, averagely. [ Conclusion] The 15 primers selected could be effectively applied to ISSR analysis of the germplasm resources of M. oblongiolus.
基金Supported by Excellent Team Training Program of Yunnan Academy of Agriculture Sciences(YAAS2014YY002)~~
文摘[Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper （Capsicum） hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Result] According to the polymorphism and heterozygosity, Hpms1-214, Es395 and Hpmsl-5 were determined as three preferred core primers for purity identification of pepper hybrids. By using these three preferred core primers, 97 pepper hybrids （accounting for 97%） had heterozygous band pattern with at least one primer. Es330, Es363, Epms923, Es120 and Es64 were determined as candidate core primers for purity identification of pepper hybrids. Specific primers of 14 varieties were obtained, which could be used to further screen parent-complementary primers of each pepper hybrid. [Con- clusion] This study laid the foundation for constructing standard DNA fingerprints for purity identification of pepper hybrids.
文摘[Objective] The aim was to explore the special methods for amplification of large-family genes by using primers with high degeneracy.[Method] By using the primers with high degeneracy,conventional PCR,conventional touchdown PCR and the optimized abnormal touchdown PCR were respectively carried out to amplify the genomic DNA of Cyprinus carpio.[Result] Only one evident electrophoretic band and a few Sox genes were obtained by using normal PCR;no obvious electrophoretic band but dispersive product was obtained by normal touchdown PCR;ideal result was obtained by the abnormal touchdown PCR that three evident electrophoretic bands and much more Sox genes were amplified.[Conclusion] The research provided theoretical basis for the optimization and selection of PCR amplification conditions of the large-family genes.
基金Supported by National Science and Technology Support Projects(No.2007BAD48B02)Agriculture Science and Technology Achievement Transformation Project(No.2007GB23260410)Basic Research Operating Expenses in Central Public Research Institutes(2007HZS1J007)~~
文摘[Objective] Grb-AST7 concatemer including 17 copies of Grb-AST7 was constructed by ＂self template-primer＂ PCR. [Method] Two primers of which were synthesized based on the amino acid sequence of Gryllus bimaculatus’ Grb-AST7. [Result] Through splicing, a length of 570 bp, containing 17 copies of the Grb-AST7 gene repeats were obtained. Appropriate primer splicing conditions were as follows：splice time 20 min, 25 μl PCR system, containing 2 μl template. [Conclusion] The results laid foundation for the future studies on Grb-AST7 gene expression and bio-activity analysis.
文摘[Objective] The aim was to explore the reasons of false positives in Different Display Reverse Transcription（DDRT）analysis.[Method] Soybean varieties ＂Jilin 30＂ and ＂Tongnong 13＂ were used as materials to carry out analysis on false positives in DDRT analysis.[Result] An important origin of false positives appeared in DDRT analysis was the non-specific amplification caused by the combination of single primer and cDNA.The parallel PCR test of single primer should be set so as to verify whether the obtained fragments were the false positives or the PCR productions combined with single primer.[Conclusion] This study had provided basis for improving the success rate of DDRT experiment.
基金Supported by Natural Science Foundation of Zhejiang Province(Y307469)Talent Start-up Fund Project of Zhejiang Agriculture and Forestry University~~
文摘[Objective] This research aimed to develop walnut EST-SSR markers and design corresponding primers.[Method] 5213 EST sequences of walnut（Juglans regia Linn.） public online in NCBI were used for character analysis with bioinformatics methods,and primers were designed for the selected EST sequences by using Primer 3.0 software.[Result] 207 SSRs were obtained from the EST sequences,including 188 non-redundant sequences,the detection rate was 3.97% with an average distribution distance of 21.12 kb.Totally 92 types of repeat motifs were involved,which were mainly composed of dinucleotide and trinucleotide,accounting for 31.40% and 35.27% of the total number of repeat motifs,respectively.30 pairs of primers were initially selected from the 50 randomly-selected SSR primers by PCR amplification.[Conclusion] This research would lay foundations for the development of EST-SSR molecular markers in walnut and design of the targeted EST-SSR primers by mining and analyzing the SSR sites in walnut EST sequences.
文摘At present,there are unharmonious factors existing in Chinese family education,which particular manifest in the means of family education.The Three Character Primer,as an epitome of the essence of Chinese traditional culture,can provide enlightenment on building a democratic and harmonious family education means.
文摘In an effort to simplify the procedure and to reduce the cost of fluorescence SSR analysis, the conditions of the multiplex PCR and the multiplex gel electrophoresis were optimized in the genetic analysis of sunflower (Helianthus annuus L.) inbred lines. Results indicated that factors for a successful multiplex PCR assay were related to the cycling touchdown annealing temperature, the balance of primer concentration at the various loci, the concentration of PCR buffer and the Taq DNA polymerase. Based on the optimization, a tailed primer strategy was outlined, and the effective ways were proposed to overcome the troubleshootings commonly encountered in the multiplex PCR and the multiplex gel electrophoresis.
基金Supported by(in part)Grants UH2CA140233 from the Human Microbiome Project of the NIH Roadmap Initiative and National Cancer InstituteR01AI063477 from the National Institute of Allergy and Infectious Diseases+1 种基金DE-11443 from the National Institute of Dental and Craniofacial ResearchU19DE018385 from the National Institute of Dental & Craniofacial Research
文摘AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.
基金This work was funded by the Special Scientific Foundation of Guangdong Province (No. A305030301)was partly supported by a grant from KLFEE, Ministry of Agriculture (2003-04).
文摘Among many reports investigating microbial diversity from environmental samples with denaturing gradient gel electrophoresis (DGGE), limited attention has been given to the effects of universal primers and DNA extraction on the outcome of DGGE analysis. In this study, these effects were tested with 16S rRNA gene-based DGGE on a bacterial community from farming water samples. The results indicate that the number of discernable bands in the DGGE fingerprint differed with the primer pairs used; the bands produced by 63f/518r, 341f/926r and 933f/1387r primer pairs were obviously fewer than those by 968f/1401r. Also, we found that each DNA extraction method resulted in different community profiles, reflected by the number and intensity of bands in the DGGE fingerprint. Furthermore, the main bands (theoretically representing dominant bacteria) differed with the extraction methods applied. It is therefore believed that the effects of universal primers and DNA extraction should be given more attention and carefully chosen before performing an investigation into a new environment with DGGE.
基金supported by the Shandong Seed Projectthe National Natural Science Foundation of China(No.31372524)Science and Technology Development Plan of Shandong Province,China(No.2014GHY 115002)
文摘There is an increasing requirement for traceability of aquaculture products, both for consumer protection and for food safety. There are high error rates in the conventional traceability systems depending on physical labels. Genetic traceability technique depending on DNA-based tracking system can overcome this problem. Genealogy information is essential for genetic traceability, and microsatellite DNA marker is a good choice for pedigree analysis. As increasing genotyping throughput of microsatellites, microsatellite multiplex PCR has become a fast and cost-effective technique. As a commercially important cultured aquatic species, Pacific oyster Crassostrea gigas has the highest global production. The objective of this study was to develop microsatellite multiplex PCR panels with dye-labeled universal primer for pedigree analysis in C. gigas, and these multiplex PCRs were validated using 12 full-sib families with known pedigrees. Here we developed six informative multiplex PCRs using 18 genomic microsatellites in C. gigas. Each multiplex panel contained a single universal primer M13(-21) used as a tail on each locus-specific forward primer and a single universal primer M13(-21) labeled with fluorophores. The polymorphisms of the markers were moderate, with an average of 10.3 alleles per locus and average polymorphic information content of 0.740. The observed heterozygosity per locus ranged from 0.492 to 0.822. Cervus simulations revealed that the six panels would still be of great value when massive families were analysed. Pedigree analysis of real offspring demonstrated that 100% of the offspring were unambiguously allocated to their parents when two multiplex PCRs were used. The six sets of multiplex PCRs can be an important tool for tracing cultured individuals, population genetic analysis, and selective breeding program in C. gigas.
基金supported by the National Natural Science Foundation of China (30700526)the Postdoctoral Science Foundation of China (55920)the Science Foundation of the Fujian Province,China (2009N0013)
文摘Tylenchulus semipenetrans is the most economically important and widespread nematode pest of citrus in China.rDNA-ITS of 14 populations of T.semipenetrans which were collected from different citrus groves or Chinese fir（Cunninghamia lanceolata） plantations in China were amplified and sequenced.The species-specific primers were designed for the first time to diagnosis T.semipenetrans based on the sequences of rDNA-ITS regions of geographic population above.The primers were sensitive to amplify the expected band size（297 bp） from DNA template of a single second-stage juvenile（J2） or different life stages of T.semipenetrans.No specific band was amplified from 15 non-target nematode species which were commonly found in citrus groves.Specificity and reliability of the primers were validated by further PCR amplification of 16 extra populations of T.semipenetrans collected from 4 provinces of China.The primers successfully detected a single J2 of T.semipenetrans within a whole nematode community comprising a large numbers of non-target nematode.The developed diagnostic technique can be used for accurate identification of T.semipenetrans and also as a decision tool for nematode management for citrus or Chinese fir in China.
