Using SRAP(sequence-related amplified polymorphism)markers a genetic linkage map of cucumber was constructed with a population consisting of 138 F_(2) individuals derived from a cross of the two cucumber lines,S06 and...Using SRAP(sequence-related amplified polymorphism)markers a genetic linkage map of cucumber was constructed with a population consisting of 138 F_(2) individuals derived from a cross of the two cucumber lines,S06 and S52.In the survey of parental polymorphisms with 182 primer combinations,64 polymorphism-revealing primer pairs were screened out,which generated totally 108 polymorphic bands with an average of 1.7 bands per primer pair and at most 6 bands from one primer pair.The constructed molecular linkage map included 92 loci,distributed in seven linkage groups and spanning 1164.2 cM in length with an average genetic distance of 12.6 cM between two neighboring loci.Based on this linkage map,the quantitative trait loci(QTL)for the lateral branch number(lbn)and the lateral branch average length(lbl)in cucumber were identified by QTLMapper1.6.A major QTL lbn1 located between ME11SA4B and ME5EM5 in LG2 could explain 10.63%of the total variation with its positively effecting allele from S06.A major QTL lbl1 located between DC1OD3 and DC1EM14 in LG2 could account for 10.38%of the total variation with its positively effecting allele from S_(06).展开更多
In the present study, we evaluated the genetic diversity of Panax notoginseng F H Chen, a domesticated species, and P. stipuleanatus H T Tsai et K M Feng, an endangered wild species in southeastern Yunnan and adjacent...In the present study, we evaluated the genetic diversity of Panax notoginseng F H Chen, a domesticated species, and P. stipuleanatus H T Tsai et K M Feng, an endangered wild species in southeastern Yunnan and adjacent areas in Vietnam, using sequences of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA and amplified fragment length polymorphism (AFLP) markers. Twenty-four accessions from three plantations of P. notoginseng and 51 samples from eight populations of P. stipuleanatus were assayed. A total of 694 bp of partial sequences of 18S, ITS 1, 5.8S, ITS2, and partial sequences of 26S were obtained. No sequence variation was detected within P. notoginseng and nine sites (1.30%) were variable in P. stipuleanatus. Two-thirds of the variable sites were found between Langqiao and other populations. In P. notoginseng, four pairs of AFLP primer combinations generated 312 bands, of which 240 (76.9%) were polymorphic and 60.15% of the polymorphisms were harbored within plantations. Approximately 41.0% and 66.9% of bands were polymorphic in population D7 and 5589, respectively. In P.stipuleanatus, the same four primer combinations produced 346 bands, of which 334 (96.5%) were polymorphic and approximately 62.14% of polymorphisms were maintained within populations. Considerable variations were observed. The percentage of polymorphic bands ranged from 50.2% to 84.9% and the average over populations was 70.9%. Cluster analysis did not show correlation of genetic differentiation with the distinctive leaf morphology of P. stipuleanatus (i.e. one form with bipinnatifid leaflets and the other with undivided leaflets). Because over 40% of genetic variations were maintained among populations and because of the very restricted distribution of P. stipuleanatus, all natural populations of this species should be conserved in situ. Considering that there are variations in P. notoginseng within and among plantations, we suggest establishing a genetic resource conservation garden or reintroducing P. notoginseng in展开更多
DNA methylation plays an important role in the epigenetic regulation of gene expression during plant growth,development,and polyploidization.However,there is still no distinct evidence in tobacco regarding the distrib...DNA methylation plays an important role in the epigenetic regulation of gene expression during plant growth,development,and polyploidization.However,there is still no distinct evidence in tobacco regarding the distribution of the methylation pattern and whether it contributes to qualitative characteristics.We studied the levels and patterns of methylation polymorphism at CCGG sites in 48 accessions of allotetraploid flue-cured tobacco,Nicotiana tabacum,using a methylation-sensitive amplified polymorphism(MSAP) technique.The results showed that methylation existed at a high level among tobacco accessions,among which 49.3% sites were methylated and 69.9% allelic sites were polymorphic.A cluster analysis revealed distinct patterns of geography-specific groups.In addition,three polymorphic sites significantly related to tobacco mosaic virus(TMV) resistance were explored.This suggests that tobacco breeders should pay more attention to epigenetic traits.展开更多
Barley(Hordeum vulgare L.)is one of the most Aluminum(Al)sensitive cereal species.In this study,the physiological,biochemical,and molecular response of barley seedlings to Al treatment was examined to gain insight int...Barley(Hordeum vulgare L.)is one of the most Aluminum(Al)sensitive cereal species.In this study,the physiological,biochemical,and molecular response of barley seedlings to Al treatment was examined to gain insight into Al response and tolerance mechanisms.The results showed that superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)activity were inhibited to different degrees following Al exposure.The MDA content also significantly increased with increasing Al concentrations.SRAP results indicated significant differences between Al treatments and controls in terms of SRAP profile,and the genomic template stability(GTS)decreased with increasing Al concentration and duration.These integrative results help to elucidate the underlying mechanisms that the barley response to Al toxicity.展开更多
The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 mate...The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 materials of P. methysticum, 21 maerials of cultivated and wild Pepper, 1 material of Peperomia pellucida belonged to different genus. Premiers with good band-type and high polymorphism and resolution were selected from 64 pairs of primers for AFLP amplification and the clustering analysis was conducted with MVSP3.13f software. 191 bands were amplified by 4 pairs of premiers, 189 of which had polymorphism, being 98.6%. 28 germplasms were classified into 6 different groups at the genetic similarity coefficient of 0.52 by silver staining AFLP, in which 6 materials of Piper methysticum were clustered into a single group, indicating that P. methysticum belonged to Pepper family of Pepper genus but were distantly related to the others. The research provided the basis for selecting rootstocks for P. methysticum graft, molecular identification of P. methysticum and the fingerprint construction of P. methysticum.展开更多
The fiber length trait （FLT） of 538 individuals from nature birch population in Maorshan region, Heilongjang, China were measured, of which 100 individuals were selected as representative variety of correlated fragm...The fiber length trait （FLT） of 538 individuals from nature birch population in Maorshan region, Heilongjang, China were measured, of which 100 individuals were selected as representative variety of correlated fragments screening with random amplified polymorphism DNA （RAPD） technique. In total of 20 RAPD primers were tested through multiple regression analysis between amplified strip and the character behaviors, and a correlative segment BFLR-16 was obtained. The correlation coefficient between BFLI-16 and FLT was 0.6144, with the significant level of 1%. BFLI-16 was then cloned, sequenced and transformed into SCAR marker. The percentage of identifying long fiber birches by this SCAR was more than 92. The result indicates that the SCAR markers has high specificity for the long fiber individuals and is highly linked with the gene controlling the character of fiber length, and its existence is significantly correlative with the increase in the fiber length.展开更多
The red alga Gracilariopsis lemaneiformis(Bory) is an economically valuable macroalgae. As a means to identify the sex of immature Gracilariopsis lemaneiformis, the amplifi ed fragment length polymorphism(AFLP) techni...The red alga Gracilariopsis lemaneiformis(Bory) is an economically valuable macroalgae. As a means to identify the sex of immature Gracilariopsis lemaneiformis, the amplifi ed fragment length polymorphism(AFLP) technique was used to search for possible sex- or phase-related markers in male gametophytes, female gametophytes, and tetrasporophytes, respectively. Seven AFLP selective amplifi cation primers were used in this study. The primer combination E-TG/M-CCA detected a specifi c band linked to male gametophytes. The DNA fragment was recovered and a 402-bp fragment was sequenced. However, no DNA sequence match was found in public databases. Sequence characterized amplifi ed region(SCAR) primers were designed from the sequence to test the repeatability of the relationship to the sex, using 69 male gametophytes, 139 female gametophytes, and 47 tetrasporophytes. The test results demonstrate a good linkage and repeatability of the SCAR marker to sex. The SCAR primers developed in this study could reduce the time required for sex identifi cation of Gracilariopsis lemaneiformis by four to six months. This can reduce both the time investment and number of specimens required in breeding experiments.展开更多
In order to evaluation the efficiency of SRAP markers on genetic diversity of Aspergillus flavus,we screened out 17sets of primer pairs which could produce clear and reproducible SRAP bands from 150 SRAP primer pairs....In order to evaluation the efficiency of SRAP markers on genetic diversity of Aspergillus flavus,we screened out 17sets of primer pairs which could produce clear and reproducible SRAP bands from 150 SRAP primer pairs.The size of SRAP fragments ranged from 120 to 2100 bp.Primer pair Me10/Em9 produced the maximum number of polymorphic bands(12 bands),while Me8/Em13 produced the fewest number of polymorphic bands(only 1).Through analysis genetic diversity ability of different sets of primer pairs,the set of 12 primer pairs was selected for SRAP genetic marker of A.flavus.Cluster analysis was performed based on the genetic similarity coefficients,which ranged from 0.53 to 0.89.A dendrogram assembled using the unweighted pair-group method with arithmetic averages grouped A.flavus samples into 5 main clusters.The results suggested that SRAP marker is a useful molecular technology for the diversity of A.flavus from peanut soils in China.展开更多
Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight sa...Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight samples from varieties "Rongfu", "Fujian", "Ailunwan" and "Shengchanzhong" were used for the genetic analyses. One hundred and ninety-eight bands were obtained using eight combinations of primers. One hundred and ninety-one (96.46%) were polymorphic bands. Nei's genetic diversity was 0.360, and the coefficient of genetic differentiation was 0.357. No inbreeding-type recession was found in the four brown alga varieties and the results of the "Ailunwan" variety using samples from 2 years showed that the variety was becoming less diverse during the selection inherent in the breeding program. Genetic diversity and cluster analyses results were consistent with these genetic relationships. The results show the RSAP method is suitable for genetic analysis. Continuous inbreeding and selection could reduce the genetic diversity effectively; therefore periodical supervision is required.展开更多
OBJECTIVE: To detect DNA and chromosomes instabilities during the progression of tumors and screen new molecular markers coupled to putative or unknown oncogenes and/or tumor suppressor genes. METHODS: Five kinds of t...OBJECTIVE: To detect DNA and chromosomes instabilities during the progression of tumors and screen new molecular markers coupled to putative or unknown oncogenes and/or tumor suppressor genes. METHODS: Five kinds of tumors, in a total of 128 specimens, were analyzed by random amplified polymorphic DNA (RAPD) PCR. Bands representing instabilities were recovered, purified, and cloned, labeled as probes for Southern and Northern blot analysis and DNA sequencing. RESULTS: Sample 5 and 3 of the gastric cancer tissues showed the highest genomic changes and the average detectability in five cancers was up to at least 40% (42.2% - 49.4%). There were significant differences in the ability of each primer to detect genomic instability, which ranged from 27% (primer 8) to 68% (primer 2). Band B is a single copy fragment, and was found to be an allelic loss in gastric and colon cancers. It is a novel sequence and was registered in GenBank with Accession Number AF151005. Further analysis revealed that it might be part of a cis-regulatory element of a new tumor suppressor gene, containing a promoter of cis-action 'CACA' box, an enhancer of 'GATA' family and a start codon. CONCLUSIONS: It was impossible or difficult to get great achievements for cancer treatments with the procedure of gene therapy only to one oncogene or one tumor suppressor gene because the extensive DNA variations occurred during the progression of tumor. RAPD assay connected with other techniques was a good tool for the detection of genomic instabilities and direct screening of some new molecular markers related to tumor suppressor genes or oncogenes.展开更多
Retrotransposons are present in all plant genomes and play important roles in genome size,genome structure remodeling,gene function and genome evolution.Me07Em02 marked by sequence-related amplified polymorphism (SRAP...Retrotransposons are present in all plant genomes and play important roles in genome size,genome structure remodeling,gene function and genome evolution.Me07Em02 marked by sequence-related amplified polymorphism (SRAP) is verified,recovered,sequenced and analyzed,which closely link to the flesh color around the stone.By comparison with the peach genome Peach v1.0,a part of the sequence of copia-like retrotransposons is obtained.With the aid of DANMAN and DNASTAR sequence analysis software,BLASTn alignment is carried out in the peach genome database and GenBank.The whole genome sequence of the copialike retrotransposon in the peach is located at 9 939 764~9 944 771 bp in Scaffold-1 of Peach v1.0,with a total length of 5 008 bp.The LTR on both sides is exactly the same,the length is 444 bp,and the largest ORF box is located at the 487~4 545 bp of the sequence,encoding 1 535 amino acids.The amino acid sequence was submitted to GenBank for Protein BLAST alignment,The results showed that this sequence also has the typical amino acid sequence characteristics of the copia-like retrotransposon.At the same time,the method of peach retrotransposon labeling is preliminarily established,and the genetic diversity of the peach is analyzed.展开更多
Objective: The self cross colonial prochordate, Botryllus schlosseri ( B.schlosseri ) occupy a key phylogenetic position in the evolution of vertebrates. To clarify the relationship of genome diversity and survive rat...Objective: The self cross colonial prochordate, Botryllus schlosseri ( B.schlosseri ) occupy a key phylogenetic position in the evolution of vertebrates. To clarify the relationship of genome diversity and survive rate, five generations of B. schlosseri was investigated by amplified fragment length polymorphism (AFLP). Methods: AFLP markers are extremely sensitive to even small sequence variation, using PCR and high resolution electrophoresis to examine restriction fragments. Results: AFLP polymorphism was high in the parent and lower in its F1, F2, F3 and F4. Each primer combination generated from 80 to more than 120 bands, of which average 25.85% polymorphic loci in parent, 15.79% polymorphic among F1, 9.16% and 5.58% in F2, F3. The AFLP markers were transmitted from F1 to F2, F3 and F4 and inherited, segregated in expected Mendelian ratio. However, some of the markers were lost in F2, F3 and F4 while it disappeared in their mother. In addition, gene mutation new loci and lost loci among F1, F2, F3 and F4 were observed. These special fragments were cloned and sequenced. Then, the genomic DNA was analyzed by Southern hybridization with the probes from these specific fragments and the mechanism of gene mutation was clarified. Conclusion: These results suggest that there are high frequency of polymorphic loci and mutation in genome of B. schlosseri. Gene deletion or low diversity may be the reason for high rate of death of the offspring of inbred laboratory reared strains.展开更多
The Cucurbita maxima Duchesne is a vegetable crop plant cultivated and maintained by traditional Amazon communities, Brazil. The situation is worsened by the possibility of disappearance of local populations and genet...The Cucurbita maxima Duchesne is a vegetable crop plant cultivated and maintained by traditional Amazon communities, Brazil. The situation is worsened by the possibility of disappearance of local populations and genetic variability of this specie, taking into account the today changes promoted in family farming. The aim of this study was to estimate the current levels of genetic variability of local cultivars through the use of molecular markers (Amplified Fragment Length Polymorphism—AFLP). We chose to collect in two distinct micro regions in order to identify possible influences of geographic isolation and different levels of market requirements in the conservation of the genetic variability of the C. maxima. For the molecular analysis, bulk samples of fresh leaves of 15 plants/half-sibling family were collected in paper bags. There were 34 samples from the half-sib families. The analysis of the results half-sib obtained by methods of estimation of genetic variation by molecular markers shows that the forms of cultivation and management adopted by family farmers maintain the identities of the local/landraces (native cultivars) and, at the same time, the levels of diversity for the assurance of adaptability macro-environmental.展开更多
A total of 10 non-repetitive multi-drug-resistant Acinetobacter strains were collected.With reference to A.calcoaceticus(ATCC23055),A.baumannii(ATCC19606),A.lwoffii(ATCC17986),and A.junii(NCTC5866),DNA fingerprint tec...A total of 10 non-repetitive multi-drug-resistant Acinetobacter strains were collected.With reference to A.calcoaceticus(ATCC23055),A.baumannii(ATCC19606),A.lwoffii(ATCC17986),and A.junii(NCTC5866),DNA fingerprint technique,amplified ribosomal DNA restriction analysis(ARDRA),and random amplified polymorphism DNA(RAPD)were carried out to identify the genomic species of Acinetobacter spp.The distances between them were calculated by the unweighted pair group method with arithmetic(UPGMA).Genotypes of Acinetobacter spp.were effectively classified and an A.junii together with nine A.baumannii isolates was genomically identified.The combination of ARDRA and RAPD DNA-fingerprint technique shows high complementarity,and could be a useful tool in Acinetobacter genomic species identification.展开更多
基金This work was support ed by the Shanghai Municipal Scientifi c&Technological Commission(Grant Nos.033107019)Shanghai Municipal Agricultural Commission(Grant Nos 2003-2-1-2).
文摘Using SRAP(sequence-related amplified polymorphism)markers a genetic linkage map of cucumber was constructed with a population consisting of 138 F_(2) individuals derived from a cross of the two cucumber lines,S06 and S52.In the survey of parental polymorphisms with 182 primer combinations,64 polymorphism-revealing primer pairs were screened out,which generated totally 108 polymorphic bands with an average of 1.7 bands per primer pair and at most 6 bands from one primer pair.The constructed molecular linkage map included 92 loci,distributed in seven linkage groups and spanning 1164.2 cM in length with an average genetic distance of 12.6 cM between two neighboring loci.Based on this linkage map,the quantitative trait loci(QTL)for the lateral branch number(lbn)and the lateral branch average length(lbl)in cucumber were identified by QTLMapper1.6.A major QTL lbn1 located between ME11SA4B and ME5EM5 in LG2 could explain 10.63%of the total variation with its positively effecting allele from S06.A major QTL lbl1 located between DC1OD3 and DC1EM14 in LG2 could account for 10.38%of the total variation with its positively effecting allele from S_(06).
基金国家重点基础研究发展计划(973计划)，中国科学院知识创新工程项目，国家自然科学基金，the Outstanding Overseas Chinese Grant of the Chinese Academy of Sciences, and the U.S. National Science Foundation Supported by，the U.S. National Science Foundation
文摘In the present study, we evaluated the genetic diversity of Panax notoginseng F H Chen, a domesticated species, and P. stipuleanatus H T Tsai et K M Feng, an endangered wild species in southeastern Yunnan and adjacent areas in Vietnam, using sequences of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA and amplified fragment length polymorphism (AFLP) markers. Twenty-four accessions from three plantations of P. notoginseng and 51 samples from eight populations of P. stipuleanatus were assayed. A total of 694 bp of partial sequences of 18S, ITS 1, 5.8S, ITS2, and partial sequences of 26S were obtained. No sequence variation was detected within P. notoginseng and nine sites (1.30%) were variable in P. stipuleanatus. Two-thirds of the variable sites were found between Langqiao and other populations. In P. notoginseng, four pairs of AFLP primer combinations generated 312 bands, of which 240 (76.9%) were polymorphic and 60.15% of the polymorphisms were harbored within plantations. Approximately 41.0% and 66.9% of bands were polymorphic in population D7 and 5589, respectively. In P.stipuleanatus, the same four primer combinations produced 346 bands, of which 334 (96.5%) were polymorphic and approximately 62.14% of polymorphisms were maintained within populations. Considerable variations were observed. The percentage of polymorphic bands ranged from 50.2% to 84.9% and the average over populations was 70.9%. Cluster analysis did not show correlation of genetic differentiation with the distinctive leaf morphology of P. stipuleanatus (i.e. one form with bipinnatifid leaflets and the other with undivided leaflets). Because over 40% of genetic variations were maintained among populations and because of the very restricted distribution of P. stipuleanatus, all natural populations of this species should be conserved in situ. Considering that there are variations in P. notoginseng within and among plantations, we suggest establishing a genetic resource conservation garden or reintroducing P. notoginseng in
基金supported by the Program for High-Quality Tobacco Development of China (No. [2010]221)the Foundation of Science and Technology of Guizhou Province (No. J[2010]2251)the Program for Guizhou Tobacco Science of China (No. 200910)
文摘DNA methylation plays an important role in the epigenetic regulation of gene expression during plant growth,development,and polyploidization.However,there is still no distinct evidence in tobacco regarding the distribution of the methylation pattern and whether it contributes to qualitative characteristics.We studied the levels and patterns of methylation polymorphism at CCGG sites in 48 accessions of allotetraploid flue-cured tobacco,Nicotiana tabacum,using a methylation-sensitive amplified polymorphism(MSAP) technique.The results showed that methylation existed at a high level among tobacco accessions,among which 49.3% sites were methylated and 69.9% allelic sites were polymorphic.A cluster analysis revealed distinct patterns of geography-specific groups.In addition,three polymorphic sites significantly related to tobacco mosaic virus(TMV) resistance were explored.This suggests that tobacco breeders should pay more attention to epigenetic traits.
基金This research was funded by National Key Technology Research and Development Program(2015BAD01B02)the National Natural Science Foundation of China(31401316).
文摘Barley(Hordeum vulgare L.)is one of the most Aluminum(Al)sensitive cereal species.In this study,the physiological,biochemical,and molecular response of barley seedlings to Al treatment was examined to gain insight into Al response and tolerance mechanisms.The results showed that superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)activity were inhibited to different degrees following Al exposure.The MDA content also significantly increased with increasing Al concentrations.SRAP results indicated significant differences between Al treatments and controls in terms of SRAP profile,and the genomic template stability(GTS)decreased with increasing Al concentration and duration.These integrative results help to elucidate the underlying mechanisms that the barley response to Al toxicity.
基金Supported by the National Key Project of Tenth-five Year Plan(2001BA707B)School Foundation Program of Henan Science and Technology University~~
文摘The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 materials of P. methysticum, 21 maerials of cultivated and wild Pepper, 1 material of Peperomia pellucida belonged to different genus. Premiers with good band-type and high polymorphism and resolution were selected from 64 pairs of primers for AFLP amplification and the clustering analysis was conducted with MVSP3.13f software. 191 bands were amplified by 4 pairs of premiers, 189 of which had polymorphism, being 98.6%. 28 germplasms were classified into 6 different groups at the genetic similarity coefficient of 0.52 by silver staining AFLP, in which 6 materials of Piper methysticum were clustered into a single group, indicating that P. methysticum belonged to Pepper family of Pepper genus but were distantly related to the others. The research provided the basis for selecting rootstocks for P. methysticum graft, molecular identification of P. methysticum and the fingerprint construction of P. methysticum.
基金supported by the National 863 Program (2002BA515B0401)National Natural Science Foundation of China (30571513)Foundation of Heilongjiang Province (GA06B301)
文摘The fiber length trait （FLT） of 538 individuals from nature birch population in Maorshan region, Heilongjang, China were measured, of which 100 individuals were selected as representative variety of correlated fragments screening with random amplified polymorphism DNA （RAPD） technique. In total of 20 RAPD primers were tested through multiple regression analysis between amplified strip and the character behaviors, and a correlative segment BFLR-16 was obtained. The correlation coefficient between BFLI-16 and FLT was 0.6144, with the significant level of 1%. BFLI-16 was then cloned, sequenced and transformed into SCAR marker. The percentage of identifying long fiber birches by this SCAR was more than 92. The result indicates that the SCAR markers has high specificity for the long fiber individuals and is highly linked with the gene controlling the character of fiber length, and its existence is significantly correlative with the increase in the fiber length.
基金Supported by the"Twelfth Five-Year-Plan"of National Science and Technology for the Rural Development in China(No.2012AA10A411)the Public Welfare Project of the Ministry of Agriculture of China(No.200903030)
文摘The red alga Gracilariopsis lemaneiformis(Bory) is an economically valuable macroalgae. As a means to identify the sex of immature Gracilariopsis lemaneiformis, the amplifi ed fragment length polymorphism(AFLP) technique was used to search for possible sex- or phase-related markers in male gametophytes, female gametophytes, and tetrasporophytes, respectively. Seven AFLP selective amplifi cation primers were used in this study. The primer combination E-TG/M-CCA detected a specifi c band linked to male gametophytes. The DNA fragment was recovered and a 402-bp fragment was sequenced. However, no DNA sequence match was found in public databases. Sequence characterized amplifi ed region(SCAR) primers were designed from the sequence to test the repeatability of the relationship to the sex, using 69 male gametophytes, 139 female gametophytes, and 47 tetrasporophytes. The test results demonstrate a good linkage and repeatability of the SCAR marker to sex. The SCAR primers developed in this study could reduce the time required for sex identifi cation of Gracilariopsis lemaneiformis by four to six months. This can reduce both the time investment and number of specimens required in breeding experiments.
基金the grants from the Natural Science Foundation of Shandong Province(ZR2020MC103,ZR2021MC040)Innovation Project of Agricultural Science and Technology of Shandong Academy of Agricultural Sciences(CXGC2022B06,CXGC2022F33)。
文摘In order to evaluation the efficiency of SRAP markers on genetic diversity of Aspergillus flavus,we screened out 17sets of primer pairs which could produce clear and reproducible SRAP bands from 150 SRAP primer pairs.The size of SRAP fragments ranged from 120 to 2100 bp.Primer pair Me10/Em9 produced the maximum number of polymorphic bands(12 bands),while Me8/Em13 produced the fewest number of polymorphic bands(only 1).Through analysis genetic diversity ability of different sets of primer pairs,the set of 12 primer pairs was selected for SRAP genetic marker of A.flavus.Cluster analysis was performed based on the genetic similarity coefficients,which ranged from 0.53 to 0.89.A dendrogram assembled using the unweighted pair-group method with arithmetic averages grouped A.flavus samples into 5 main clusters.The results suggested that SRAP marker is a useful molecular technology for the diversity of A.flavus from peanut soils in China.
基金Supported by the National Special Research Fund for Non-Profit Sector(No.200805075)the Shandong Foundation for Development of Scienceand Technology, China (No.2007GG10005018)+2 种基金the Genetically Modified Organism Technology Major Project (No.2009ZX08009-100B)the National High Technology Research and Development Program of China(863 Program) (Nos.2010AA10A401,2012AA10A406)the National Agricultural Transformation (No.2010GB23600666)
文摘Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight samples from varieties "Rongfu", "Fujian", "Ailunwan" and "Shengchanzhong" were used for the genetic analyses. One hundred and ninety-eight bands were obtained using eight combinations of primers. One hundred and ninety-one (96.46%) were polymorphic bands. Nei's genetic diversity was 0.360, and the coefficient of genetic differentiation was 0.357. No inbreeding-type recession was found in the four brown alga varieties and the results of the "Ailunwan" variety using samples from 2 years showed that the variety was becoming less diverse during the selection inherent in the breeding program. Genetic diversity and cluster analyses results were consistent with these genetic relationships. The results show the RSAP method is suitable for genetic analysis. Continuous inbreeding and selection could reduce the genetic diversity effectively; therefore periodical supervision is required.
文摘OBJECTIVE: To detect DNA and chromosomes instabilities during the progression of tumors and screen new molecular markers coupled to putative or unknown oncogenes and/or tumor suppressor genes. METHODS: Five kinds of tumors, in a total of 128 specimens, were analyzed by random amplified polymorphic DNA (RAPD) PCR. Bands representing instabilities were recovered, purified, and cloned, labeled as probes for Southern and Northern blot analysis and DNA sequencing. RESULTS: Sample 5 and 3 of the gastric cancer tissues showed the highest genomic changes and the average detectability in five cancers was up to at least 40% (42.2% - 49.4%). There were significant differences in the ability of each primer to detect genomic instability, which ranged from 27% (primer 8) to 68% (primer 2). Band B is a single copy fragment, and was found to be an allelic loss in gastric and colon cancers. It is a novel sequence and was registered in GenBank with Accession Number AF151005. Further analysis revealed that it might be part of a cis-regulatory element of a new tumor suppressor gene, containing a promoter of cis-action 'CACA' box, an enhancer of 'GATA' family and a start codon. CONCLUSIONS: It was impossible or difficult to get great achievements for cancer treatments with the procedure of gene therapy only to one oncogene or one tumor suppressor gene because the extensive DNA variations occurred during the progression of tumor. RAPD assay connected with other techniques was a good tool for the detection of genomic instabilities and direct screening of some new molecular markers related to tumor suppressor genes or oncogenes.
文摘Retrotransposons are present in all plant genomes and play important roles in genome size,genome structure remodeling,gene function and genome evolution.Me07Em02 marked by sequence-related amplified polymorphism (SRAP) is verified,recovered,sequenced and analyzed,which closely link to the flesh color around the stone.By comparison with the peach genome Peach v1.0,a part of the sequence of copia-like retrotransposons is obtained.With the aid of DANMAN and DNASTAR sequence analysis software,BLASTn alignment is carried out in the peach genome database and GenBank.The whole genome sequence of the copialike retrotransposon in the peach is located at 9 939 764~9 944 771 bp in Scaffold-1 of Peach v1.0,with a total length of 5 008 bp.The LTR on both sides is exactly the same,the length is 444 bp,and the largest ORF box is located at the 487~4 545 bp of the sequence,encoding 1 535 amino acids.The amino acid sequence was submitted to GenBank for Protein BLAST alignment,The results showed that this sequence also has the typical amino acid sequence characteristics of the copia-like retrotransposon.At the same time,the method of peach retrotransposon labeling is preliminarily established,and the genetic diversity of the peach is analyzed.
文摘Objective: The self cross colonial prochordate, Botryllus schlosseri ( B.schlosseri ) occupy a key phylogenetic position in the evolution of vertebrates. To clarify the relationship of genome diversity and survive rate, five generations of B. schlosseri was investigated by amplified fragment length polymorphism (AFLP). Methods: AFLP markers are extremely sensitive to even small sequence variation, using PCR and high resolution electrophoresis to examine restriction fragments. Results: AFLP polymorphism was high in the parent and lower in its F1, F2, F3 and F4. Each primer combination generated from 80 to more than 120 bands, of which average 25.85% polymorphic loci in parent, 15.79% polymorphic among F1, 9.16% and 5.58% in F2, F3. The AFLP markers were transmitted from F1 to F2, F3 and F4 and inherited, segregated in expected Mendelian ratio. However, some of the markers were lost in F2, F3 and F4 while it disappeared in their mother. In addition, gene mutation new loci and lost loci among F1, F2, F3 and F4 were observed. These special fragments were cloned and sequenced. Then, the genomic DNA was analyzed by Southern hybridization with the probes from these specific fragments and the mechanism of gene mutation was clarified. Conclusion: These results suggest that there are high frequency of polymorphic loci and mutation in genome of B. schlosseri. Gene deletion or low diversity may be the reason for high rate of death of the offspring of inbred laboratory reared strains.
文摘The Cucurbita maxima Duchesne is a vegetable crop plant cultivated and maintained by traditional Amazon communities, Brazil. The situation is worsened by the possibility of disappearance of local populations and genetic variability of this specie, taking into account the today changes promoted in family farming. The aim of this study was to estimate the current levels of genetic variability of local cultivars through the use of molecular markers (Amplified Fragment Length Polymorphism—AFLP). We chose to collect in two distinct micro regions in order to identify possible influences of geographic isolation and different levels of market requirements in the conservation of the genetic variability of the C. maxima. For the molecular analysis, bulk samples of fresh leaves of 15 plants/half-sibling family were collected in paper bags. There were 34 samples from the half-sib families. The analysis of the results half-sib obtained by methods of estimation of genetic variation by molecular markers shows that the forms of cultivation and management adopted by family farmers maintain the identities of the local/landraces (native cultivars) and, at the same time, the levels of diversity for the assurance of adaptability macro-environmental.
基金This study was supported by the Natural Science Research Program of Universities and Colleges of Anhui Province,China(No.2006kj349B).
文摘A total of 10 non-repetitive multi-drug-resistant Acinetobacter strains were collected.With reference to A.calcoaceticus(ATCC23055),A.baumannii(ATCC19606),A.lwoffii(ATCC17986),and A.junii(NCTC5866),DNA fingerprint technique,amplified ribosomal DNA restriction analysis(ARDRA),and random amplified polymorphism DNA(RAPD)were carried out to identify the genomic species of Acinetobacter spp.The distances between them were calculated by the unweighted pair group method with arithmetic(UPGMA).Genotypes of Acinetobacter spp.were effectively classified and an A.junii together with nine A.baumannii isolates was genomically identified.The combination of ARDRA and RAPD DNA-fingerprint technique shows high complementarity,and could be a useful tool in Acinetobacter genomic species identification.
