Reproduction and development are complex couple-dependent processes. Risk assessment for these health outcomes requires the use of biomarkers to link exposures to disease. Biological markers of susceptability, externa...Reproduction and development are complex couple-dependent processes. Risk assessment for these health outcomes requires the use of biomarkers to link exposures to disease. Biological markers of susceptability, external dose, internal dose, biologically effective dose, early or late biological responses, altered reproductive or developmental function, and reproductive or developmental disease are introduced. Using these biomarkers it is possible to define a biologically based risk assessment methodology for reproductive and developmental toxicity. Risk assessment for reproductive toxicity requires definition of male and female fecundity, couple-specific factors, spontaneous abortion, rate, and other factors. Using using sperm count as a biomarker for male fecundity, an example of a reproductive risk assessment using biomarkers is performed.展开更多
Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecula...Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology,quantitative genetics and genomics. Therefore,it is extremely necessary to select several versatile,low-cost,efficient and time-and labor-saving methods to develop a large panel of microsatellite markers. In this study,we used Zhikong scallop(Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency,while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time-and cost-saving,it is difficult to obtain a large number of microsatellite markers,mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study,we recommend two methods,microsatellite-enriched library construction method and FIASCO-colony hybridization method,for large-scale microsatellite marker development. Both methods were derived from the microsatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes.展开更多
While the importance of molecular marker technology was realized more than two decades ago,high-throughput marker development came into vogue only after the availability of hundreds of thousands of sequences in public...While the importance of molecular marker technology was realized more than two decades ago,high-throughput marker development came into vogue only after the availability of hundreds of thousands of sequences in public databases.Many examples now exist where markers are being used routinely in breeding programs for marker-assisted selection(MAS) of traits of interest or marker assisted recovery of genome of interest.Genetic analysis with thousands to tens of thousands of markers is now possible due to the...展开更多
Chili pepper (Capsicum spp.) fruit color is an important agronomical trait. It has been known that a large deletion in the 5' upstream region of the Ccs gene generates non-red fruit color in pepper, but the accura...Chili pepper (Capsicum spp.) fruit color is an important agronomical trait. It has been known that a large deletion in the 5' upstream region of the Ccs gene generates non-red fruit color in pepper, but the accurate size and position of the deletion and whether all the non-red cultivars had the same large deletion or not were unclarified. In this study, to identify the Ccs upstream large deletion, we carried out diagnostic PCR using six forward primers at 300 - 900 bp intervals in the 5' untranslated region of Ccs with a fixed reverse primer for a yellow fruit pepper “Sonia Gold”. Then it was revealed that 4430 bp from -3234 bp position in upstream region to 1196 bp position in exon was deleted in Ccs of “Sonia Gold”. The allele having this deletion was named ccs-del. Probably this allele is substantially the same as ccs-p1 having 4879 bp deletion reported previously. Based on the sequence determined, we developed a PCR marker to distinguish ccs-del. Genotyping of 16 cultivars of C. annuum showed that 14 had ccs-del and the remaining two had another mutant allele ccs-3. This result indicates that ccs-del is the most common allele and widely shared in non-red fruit cultivars in C. annuum. Genotyping of 16 cultivars of C. chinense clarified that one cultivar each possessed ccs-del and ccs-3. These results indicate that major alleles responsible for non-red fruit color in C. annuum were shared across species throughout interspecific introgression.展开更多
The next - generation sequencing platform has revealed the genomic sequences of numer-ous plant species that are ideal resources for simple sequence repeat （SSR） locus screening. In this stud-y, we performed a ...The next - generation sequencing platform has revealed the genomic sequences of numer-ous plant species that are ideal resources for simple sequence repeat （SSR） locus screening. In this stud-y, we performed a comparative genomic SSR analysis on 9 sequenced plants. This showed that the total numbers of mono-, di-, tri-, tetra-, penta-, and hexa-nucleotide repeat SSRs and compound SSRs ranged from 45,552 to 326,319, and the frequencies varied from 177.9 to 573.7 with an average of 401. 3 per Mb. The SSR numbers decreased as the size of the repeat unit increased. The mono-and di-nucleotide SSRs and compound SSRs accounted for more than 78% of the total SSRs in these plants. A/T-rich re-peat motifs were generally dominant in most plants. The sizes of different SSRs varied from 10 to 7288 bp, but at least 85% of them were less than 45 bp. The polymorphism rates of different SSR types ranged from 1.5% to 14.4% in Sesamum indicum, and the mono- and di-nucleotide SSRs displayed the highest polymorphism, followed by the compound SSRs （11.2% ） . These results provide comprehensive insight into the SSR loci of plants and serve as an experimental reference for improvement of SSR marker devel-opment based on plant genomic sequences.展开更多
Fructans are major nonstructural carbohydrates in wheat （Triticum aestivum L.）. Fructan 1-fructosyltransferase （1-FFT） is the key enzyme in fructan biosynthesis. In the present study, 96 sequence variants were det...Fructans are major nonstructural carbohydrates in wheat （Triticum aestivum L.）. Fructan 1-fructosyltransferase （1-FFT） is the key enzyme in fructan biosynthesis. In the present study, 96 sequence variants were detected in the 1-FFT-A 1 gene among 26 wheat accessions including UR208, and 15 of them result in amino acid substitutions, forming four haplotypes. Two markers M39 and M2164 were developed based on the InDe121-39 and SNP-2164 polymorphisms to distinguish the three haplotypes in the 1-FFT-AI. 1-FFT-A1 was located on chromosome 4A using marker M2164 and was flanked by markers Xcwm27 and 6-SFT-A 1. By association analysis using a natural wheat population consisted of 154 accessions, the results showed that the two markers were significantly associated with water-soluble carbohydrate （WSC） content in the lower internode stem and total stem at the early and middle grain filling stages, 1 000-grain weight （TGW） at different grain filling stages and peduncle length （PLE）. Comparison of the effects of three haplotypes on agronomic traits indicated that TGW, PLE and total number of spikelets per spike （TNSS）were significantly influenced by haplotypes. Haplll showed a significant positive effect on TGW, PLE and TNSS.展开更多
Adzuki bean(Vigna angularis(Willd.)Ohwi&Ohashi)is an annual cultivated leguminous crop commonly grown in Asia and consumed worldwide.However,there has been limited research regarding adzuki bean genetics,which has...Adzuki bean(Vigna angularis(Willd.)Ohwi&Ohashi)is an annual cultivated leguminous crop commonly grown in Asia and consumed worldwide.However,there has been limited research regarding adzuki bean genetics,which has prevented the efficient application of genes during breeding.In the present study,we constructed a high-density genetic map based on whole genome re-sequencing technology and validated its utility by mining QTLs related to seed size.Moreover,we analyzed the sequences flanking insertions/deletions(In Dels)to develop a set of PCR-based markers useful for characterizing adzuki bean genetics.A total of 2904 markers were mapped to 11 linkage groups(LGs).The total length of the map was 1365.0 cM,with an average distance between markers of 0.47 cM.Among the LGs,the number of markers ranged from 208(LG7)to 397(LG1)and the total distance ranged from 97.4 cM(LG9)to 155.6 cM(LG1).Twelve QTLs related to seed size were identified using the constructed map.The two major QTLs in LG2 and LG9 explained 22.1 and 18.8%of the total phenotypic variation,respectively.Ten minor QTLs in LG4,LG5 and LG6 explained 3.0–10.4%of the total phenotypic variation.A total of 9718 primer pairs were designed based on the sequences flanking In Dels.Among the 200 selected primer pairs,75 revealed polymorphisms in 24 adzuki bean germplasms.The genetic map constructed in this study will be useful for screening genes related to other traits.Furthermore,the QTL analysis of seed size and the novel markers described herein may be relevant for future molecular investigations of adzuki bean and will be useful for exploiting the mechanisms underlying legume seed development.展开更多
文摘Reproduction and development are complex couple-dependent processes. Risk assessment for these health outcomes requires the use of biomarkers to link exposures to disease. Biological markers of susceptability, external dose, internal dose, biologically effective dose, early or late biological responses, altered reproductive or developmental function, and reproductive or developmental disease are introduced. Using these biomarkers it is possible to define a biologically based risk assessment methodology for reproductive and developmental toxicity. Risk assessment for reproductive toxicity requires definition of male and female fecundity, couple-specific factors, spontaneous abortion, rate, and other factors. Using using sperm count as a biomarker for male fecundity, an example of a reproductive risk assessment using biomarkers is performed.
基金supported by ‘863’ Program (2006AA10A408 and 2006AA10A411), NSFC30571417, NYHYZX07-047, 2005DKA30470, 2006BAD09A10 and NCET-06-0594.
文摘Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology,quantitative genetics and genomics. Therefore,it is extremely necessary to select several versatile,low-cost,efficient and time-and labor-saving methods to develop a large panel of microsatellite markers. In this study,we used Zhikong scallop(Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency,while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time-and cost-saving,it is difficult to obtain a large number of microsatellite markers,mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study,we recommend two methods,microsatellite-enriched library construction method and FIASCO-colony hybridization method,for large-scale microsatellite marker development. Both methods were derived from the microsatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes.
文摘While the importance of molecular marker technology was realized more than two decades ago,high-throughput marker development came into vogue only after the availability of hundreds of thousands of sequences in public databases.Many examples now exist where markers are being used routinely in breeding programs for marker-assisted selection(MAS) of traits of interest or marker assisted recovery of genome of interest.Genetic analysis with thousands to tens of thousands of markers is now possible due to the...
文摘Chili pepper (Capsicum spp.) fruit color is an important agronomical trait. It has been known that a large deletion in the 5' upstream region of the Ccs gene generates non-red fruit color in pepper, but the accurate size and position of the deletion and whether all the non-red cultivars had the same large deletion or not were unclarified. In this study, to identify the Ccs upstream large deletion, we carried out diagnostic PCR using six forward primers at 300 - 900 bp intervals in the 5' untranslated region of Ccs with a fixed reverse primer for a yellow fruit pepper “Sonia Gold”. Then it was revealed that 4430 bp from -3234 bp position in upstream region to 1196 bp position in exon was deleted in Ccs of “Sonia Gold”. The allele having this deletion was named ccs-del. Probably this allele is substantially the same as ccs-p1 having 4879 bp deletion reported previously. Based on the sequence determined, we developed a PCR marker to distinguish ccs-del. Genotyping of 16 cultivars of C. annuum showed that 14 had ccs-del and the remaining two had another mutant allele ccs-3. This result indicates that ccs-del is the most common allele and widely shared in non-red fruit cultivars in C. annuum. Genotyping of 16 cultivars of C. chinense clarified that one cultivar each possessed ccs-del and ccs-3. These results indicate that major alleles responsible for non-red fruit color in C. annuum were shared across species throughout interspecific introgression.
文摘The next - generation sequencing platform has revealed the genomic sequences of numer-ous plant species that are ideal resources for simple sequence repeat （SSR） locus screening. In this stud-y, we performed a comparative genomic SSR analysis on 9 sequenced plants. This showed that the total numbers of mono-, di-, tri-, tetra-, penta-, and hexa-nucleotide repeat SSRs and compound SSRs ranged from 45,552 to 326,319, and the frequencies varied from 177.9 to 573.7 with an average of 401. 3 per Mb. The SSR numbers decreased as the size of the repeat unit increased. The mono-and di-nucleotide SSRs and compound SSRs accounted for more than 78% of the total SSRs in these plants. A/T-rich re-peat motifs were generally dominant in most plants. The sizes of different SSRs varied from 10 to 7288 bp, but at least 85% of them were less than 45 bp. The polymorphism rates of different SSR types ranged from 1.5% to 14.4% in Sesamum indicum, and the mono- and di-nucleotide SSRs displayed the highest polymorphism, followed by the compound SSRs （11.2% ） . These results provide comprehensive insight into the SSR loci of plants and serve as an experimental reference for improvement of SSR marker devel-opment based on plant genomic sequences.
基金supported by the National Natural Science Foundation of China(31461143024)the National Major Project for Developing New Genetically Modified(GM) Crops of China(2016ZX08010005)the Agricultural Science and Technology Innovation Program,China(ASTIP)
文摘Fructans are major nonstructural carbohydrates in wheat （Triticum aestivum L.）. Fructan 1-fructosyltransferase （1-FFT） is the key enzyme in fructan biosynthesis. In the present study, 96 sequence variants were detected in the 1-FFT-A 1 gene among 26 wheat accessions including UR208, and 15 of them result in amino acid substitutions, forming four haplotypes. Two markers M39 and M2164 were developed based on the InDe121-39 and SNP-2164 polymorphisms to distinguish the three haplotypes in the 1-FFT-AI. 1-FFT-A1 was located on chromosome 4A using marker M2164 and was flanked by markers Xcwm27 and 6-SFT-A 1. By association analysis using a natural wheat population consisted of 154 accessions, the results showed that the two markers were significantly associated with water-soluble carbohydrate （WSC） content in the lower internode stem and total stem at the early and middle grain filling stages, 1 000-grain weight （TGW） at different grain filling stages and peduncle length （PLE）. Comparison of the effects of three haplotypes on agronomic traits indicated that TGW, PLE and total number of spikelets per spike （TNSS）were significantly influenced by haplotypes. Haplll showed a significant positive effect on TGW, PLE and TNSS.
基金supported by the National Key Research&Development Program of China(2019YFD1001300 and 2019YFD1001303)the earmarked fund for China Agriculture Research System(CARS-08)the Agricultural Science Technology Innovation Program(ASTIP)of Chinese Academy of Agricultural Sciences。
文摘Adzuki bean(Vigna angularis(Willd.)Ohwi&Ohashi)is an annual cultivated leguminous crop commonly grown in Asia and consumed worldwide.However,there has been limited research regarding adzuki bean genetics,which has prevented the efficient application of genes during breeding.In the present study,we constructed a high-density genetic map based on whole genome re-sequencing technology and validated its utility by mining QTLs related to seed size.Moreover,we analyzed the sequences flanking insertions/deletions(In Dels)to develop a set of PCR-based markers useful for characterizing adzuki bean genetics.A total of 2904 markers were mapped to 11 linkage groups(LGs).The total length of the map was 1365.0 cM,with an average distance between markers of 0.47 cM.Among the LGs,the number of markers ranged from 208(LG7)to 397(LG1)and the total distance ranged from 97.4 cM(LG9)to 155.6 cM(LG1).Twelve QTLs related to seed size were identified using the constructed map.The two major QTLs in LG2 and LG9 explained 22.1 and 18.8%of the total phenotypic variation,respectively.Ten minor QTLs in LG4,LG5 and LG6 explained 3.0–10.4%of the total phenotypic variation.A total of 9718 primer pairs were designed based on the sequences flanking In Dels.Among the 200 selected primer pairs,75 revealed polymorphisms in 24 adzuki bean germplasms.The genetic map constructed in this study will be useful for screening genes related to other traits.Furthermore,the QTL analysis of seed size and the novel markers described herein may be relevant for future molecular investigations of adzuki bean and will be useful for exploiting the mechanisms underlying legume seed development.
