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1.
Diego Breviario Wm. Vance Baird Shail Sangoi Khidir Hilu Pietro Blumetti Silvia Gianì 《Molecular breeding : new strategies in plant improvement》2007,20(3):249-259
Tubulin-Based-Polymorphism (TBP) was originally introduced as a novel method for assaying genetic diversity in plants. TBP
is based on polymorphism resulting from the PCR-mediated amplification of the first intron in the coding region of the β-tubulin
gene family. Although, the method was successful in genetic assessment of some plant species and varieties, it suffered from
low number of molecular markers due to limited variation in the first intron of β-tubulin gene family. We have now rectified
this limitation by introducing the second intron of the β-tubulin genes as a valuable source of molecular markers. We show
that the combined use of the two introns substantially increases the number of molecular markers and results in a reliable
assessment of species/varieties relationships. After a preliminary validation on Brassica, this new combinatorial method was tested on species of Eleusine and Arachis. For both, reliable assessment of species relationships were obtained that were consistent with recently published studies
resulting from more elaborated methods including DNA sequencing. Combinatorial TBP is a reliable, reproducible, simple, fast,
and easy to score method that is very useful for breeding programs and species and variety assessments. 相似文献
2.
Murat Akkurt Leocir Welter Erika Maul Reinhard Töpfer Eva Zyprian 《Molecular breeding : new strategies in plant improvement》2007,19(2):103-111
Sequence-characterized amplified regions markers (SCARs) were developed from six randomly amplified polymorphic DNA (RAPD)
markers linked to the major QTL region for powdery mildew (Uncinula necator) resistance in a test population derived from the cross of grapevine cultivars “Regent” (resistant) × “Lemberger”(susceptible).
RAPD products were cloned and sequenced. Primer pairs with at least 21 nucleotides primer length were designed. All pairs
were tested in the F1 progeny of “Regent” × “Lemberger”. The SCAR primers resulted in the amplification of specific bands
of expected sizes and were tested in additional genetic resources of resistant and susceptible germplasm. All SCAR primer
pairs resulted in the amplification of specific fragments. Two of the SCAR markers named ScORA7-760 and ScORN3-R produced
amplification products predominantly in resistant individuals and were found to correlate to disease resistance. ScORA7-760,
in particular, is suitable for marker-assisted selection for powdery mildew resistance and to facilitate pyramiding powdery
mildew resistance genes from various sources. 相似文献
3.
Characterization of a cell wall invertase gene TaCwi-A1 on common wheat chromosome 2A and development of functional markers 总被引:2,自引:0,他引:2
Dongyun Ma Jun Yan Zhonghu He Ling Wu Xianchun Xia 《Molecular breeding : new strategies in plant improvement》2012,29(1):43-52
Cell wall invertase (CWI) is a critical enzyme for sink tissue development and carbon partition, and has a high association
with kernel weight. Characterization of Cwi genes and development of functional markers are of importance for marker-assisted selection in wheat breeding. In the present
study, the full-length genomic DNA sequence of a Cwi gene located on wheat chromosome 2A, designated TaCwi-A1, was characterized by in silico cloning and experimental validation. TaCwi-A1 comprises seven exons and six introns, with 3,676 bp in total, and an open reading frame (ORF) of 1,767 bp. A pair of complementary
dominant markers, CWI21 and CWI22, was developed based on allelic variations at the TaCwi-A1 locus. A 404-bp PCR fragment was amplified by CWI21 in varieties with lower kernel weights, whereas a 402-bp fragment was
generated by CWI22 in the varieties with higher kernel weights. The markers CWI21 and CWI22 were located on chromosome 2AL
using a F2:3 population from a cross Doumai/Shi 4185, and a set of Chinese Spring nullisomic–tetrasomic lines. They were linked to the
SSR locus Xbarc15-2AL with a genetic distance of 10.9 cM. QTL analysis indicated that TaCwi-A1 could explain 4.8% of phenotypic variance for kernel weight over 2 years. Two sets of Chinese landraces and two sets of commercial
wheat varieties were used to validate the association of CWI21 and CWI22 with kernel weight. The results indicated that the
functional markers CWI21 and CWI22 were closely related to kernel weight and could be used in wheat breeding for improving
grain yield. 相似文献
4.
Stuart W. A’Hara Joan Elizabeth Cottrell 《Molecular breeding : new strategies in plant improvement》2009,23(2):349-355
Robust, polymorphic microsatellite DNA markers (simple sequence repeats—SSRs) are valuable tools for a range of tree conservation
and breeding applications. SSRs are routinely used in the study of population genetic structure and diversity, pedigree reconstruction
and genetic linkage mapping. Their abundance in the genome, co-dominant inheritance and potential for cross-species amplification
make microsatellites highly prized markers. This paper characterises 22 novel genomic polymorphic microsatellite loci for
Sitka spruce (Picea sitchensis (Bong.) Carr.). Amplification of DNA from Sitka spruce material was carried out both with a set of unrelated trees to obtain
diversity statistics for each locus, and with the progeny of a full-sib family to test simple Mendelian inheritance. Observed
heterozygosity ranged from 0.38 to 0.91 and allele number per locus ranged from 6 to 21, with a mean of 12.2. In addition,
the primer pairs were tested with DNA from Norway spruce (P. abies) and white spruce (P. glauca) to investigate their potential for cross-species amplification and ten loci amplified in all three species. The results
from these genomic microsatellites are compared to data generated from microsatellites derived from Picea EST libraries. In summary, this novel, highly polymorphic markers represent a significant addition to the rapidly expanding
Picea genomics tool-box.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
5.
Peter Westermeier Gerhard Wenzel Volker Mohler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(7):1301-1311
Single-nucleotide polymorphisms (SNPs) and insertion–deletions (INDELs) are currently the important classes of genetic markers
for major crop species. In this study, methods for developing SNP markers in rapeseed (Brassica napus L.) and their in silico mapping and use for genotyping are demonstrated. For the development of SNP and INDEL markers, 181
fragments from 121 different gene sequences spanning 86 kb were examined. A combination of different selection methods (genome-specific
amplification, hetero-duplex analysis and sequence analysis) allowed the detection of 18 singular fragments that showed a
total of 87 SNPs and 6 INDELs between 6 different rapeseed varieties. The average frequency of sequence polymorphism was estimated
to be one SNP every 247 bp and one INDEL every 3,583 bp. Most SNPs and INDELs were found in non-coding regions. Polymorphism
information content values for SNP markers ranged between 0.02 and 0.50 in a set of 86 varieties. Using comparative genetics
data for B. napus and Arabidopsis thaliana, an allocation of SNP markers to linkage groups in rapeseed was achieved: a unique location was determined for seven gene
sequences; two and three possible locations were found for six and four sequences, respectively. The results demonstrate the
usefulness of existing genomic resources for SNP discovery in rapeseed. 相似文献
6.
A new SNP haplotype associated with blue disease resistance gene in cotton (Gossypium hirsutum L.) 总被引:1,自引:0,他引:1
David D. Fang Jinhua Xiao Paulo C. Canci Roy G. Cantrell 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(5):943-953
Resistance to cotton blue disease (CBD) was evaluated in 364 F2.3 families of three populations derived from resistant variety ‘Delta Opal’. The CBD resistance in ‘Delta Opal’ was controlled
by one single dominant gene designated Cbd. Two simple sequence repeat (SSR) markers were identified as linked to Cbd by bulked segregant analysis. Cbd resides at the telomere region of chromosome 10. SSR marker DC20027 was 0.75 cM away from Cbd. DC20027 marker fragments amplified from 3 diploid species and 13 cotton varieties whose CBD resistance was known were cloned
and sequenced. One single nucleotide polymorphism (SNP) was identified at the 136th position by sequence alignment analysis.
Screening SNP markers previously mapped on chromosome 10 identified an additional 3 SNP markers that were associated with
Cbd. A strong association between a haplotype based on four SNP markers and Cbd was developed. This demonstrates one of the first examples in cotton where SNP markers were used to effectively tag a trait
enabling marker-assisted selection for high levels of CBD resistance in breeding programs. 相似文献
7.
Wesley K. Savage 《Conservation Genetics》2008,9(6):1707-1710
Habitat loss is the single greatest threat to persistence of the critically threatened California tiger salamander (Ambystoma californiense). To aid management plans that designate critical habitat for this species, I developed and characterized 21 tetranucleotide
microsatellite markers using two native populations in Santa Barbara and Alameda Counties. Allelic variation and average heterozygosities
were lower in the endangered Santa Barbara population (allele range 1–4, mean 2.4; H
O = 0.308 H
E = 0.288) compared with the threatened Alameda population (allele range 2–10, mean 6.7; H
O = 0.712, H
E = 0.722). In-depth population studies using these markers will provide vital information for plans to assign critical habitat
that optimize gene flow among breeding populations, as well as for identifying non-native hybrid genotypes that threaten native
A. californiense stocks. Beyond the conservation goals for A. californiense, the close phylogenetic relationships within the tiger salamander complex also suggest a broad utility for population studies
using these markers. 相似文献
8.
V. G. M. Bus D. Chagné H. C. M. Bassett D. Bowatte F. Calenge J.-M. Celton C.-E. Durel M. T. Malone A. Patocchi A. C. Ranatunga E. H. A. Rikkerink D. S. Tustin J. Zhou S. E. Gardiner 《Tree Genetics & Genomes》2008,4(2):223-236
Woolly apple aphid (WAA; Eriosoma lanigerum Hausm.) can be a major economic problem to apple growers in most parts of the world, and resistance breeding provides a sustainable
means to control this pest. We report molecular markers for three genes conferring WAA resistance and placing them on two
linkage groups (LG) on the genetic map of apple. The Er1 and Er2 genes derived from ‘Northern Spy’ and ‘Robusta 5,’ respectively, are the two major genes that breeders have used to date
to improve the resistance of apple rootstocks to this pest. The gene Er3, from ‘Aotea 1’ (an accession classified as Malus sieboldii), is a new major gene for WAA resistance. Genetic markers linked to the Er1 and Er3 genes were identified by screening random amplification of polymorphic deoxyribonucleic acid (DNA; RAPD) markers across DNA
bulks from resistant and susceptible plants from populations segregating for these genes. The closest RAPD markers were converted
into sequence-characterized amplified region markers and the genome location of these two genes was assigned to LG 08 by aligning
the maps around the genes with a reference map of ‘Discovery’ using microsatellite markers. The Er2 gene was located on LG 17 of ‘Robusta 5’ using a genetic map developed in a M.9 × ‘Robusta 5’ progeny. Markers for each of
the genes were validated for their usefulness for marker-assisted selection in separate populations. The potential use of
the genetic markers for these genes in the breeding of apple cultivars with durable resistance to WAA is discussed. 相似文献
9.
Effect of radiation on regeneration of Chinese narcissus and analysis of genetic variation with AFLP and RAPD markers 总被引:1,自引:0,他引:1
Gang Lu Xiaoying Zhang Yijing Zou Qingcheng Zou Xun Xiang Jiashu Cao 《Plant Cell, Tissue and Organ Culture》2007,88(3):319-327
The aim of our study was to establish an efficient in vitro propagation protocol for Chinese narcissus (Narcissus tazetta var. chinensis) to obtain variants of this species using γ-radiation treatment and evaluate the effectiveness of this system for variant
induction using amplification fragment length polymorphism (AFLP) and randomly amplified polymorphic DNA (RAPD) analysis.
Various doses (5–100 Gy) of gamma rays were applied to investigate the effect of radiation on adventitious bud formation from
bulb-scales and the survival rate of plantlets. It was demonstrated that the regeneration of Chinese narcissus was very sensitive
to gamma radiation even at low doses. The survival and multiplication rate significantly decreased with an increase of radiation
dose. The optimal irradiation dose for survival and mutation induction was approximately 10 Gy. The genetic variations among
the regenerants derived from irradiated explants were evaluated by DNA fingerprinting using RAPD and AFLP markers which detected
a variation frequency of 8.33% and 15.48% respectively. The high frequency of mutants detected by molecular markers indicated
that treatment of in vitro cultures with γ-rays may be an effective way to improve narcissus cultivars. 相似文献
10.
Fraser LG McNeilage MA Tsang GK Harvey CF De Silva HN 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,112(1):149-157
Microsatellite marker transfer across species in the dioecious genus Actinidia (kiwifruit) could offer an efficient and time-effective technique for use during trait transfer for vine and fruit improvement in breeding programmes. We evaluated the cross-species amplification of 20 EST-derived microsatellite markers that were fully informative in an Actinidia chinensis mapping family. We tested all 20 markers on 120 genotypes belonging to 21 species, 5 with varieties and/or chromosome races. These 26 taxa included 16 diploids, 7 tetraploids, 2 hexaploids and 1 octaploid, and represented all four taxonomic sections in the genus. All 20 markers showed some level of cross-species amplification. The most successful marker amplified in all genotypes from all species from all sections of the genus, the least successful amplified fragments only in A. chinensis and A. deliciosa. One species, A. glaucophylla, failed to amplify with all but 2 markers. PIC (Polymorphism information content) values were high, with 14 of 17 markers recording values of 0.90 and above. Sequence data demonstrated the presence of the microsatellite in all the amplified products. Sequence homology was less 5′ of the microsatellite and increased toward the start codon of the translated region of the EST from which the marker was derived. The data confirm that EST-derived microsatellite markers from Actinidia species show cross-species amplification with high levels of polymorphism which could make them useful markers in breeding programmes. 相似文献
11.
L. S. Lima K. P. Gramacho A. S. Gesteira U. V. Lopes F. A. Gaiotto H. A. Zaidan J. L. Pires J. C. M. Cascardo F. Micheli 《Molecular breeding : new strategies in plant improvement》2008,22(2):315-318
Theobroma cacao L.–Moniliophthora perniciosa expressed sequence tags (ESTs) were converted into useful satellite markers for population analysis and genetic mapping.
Forty-nine flanking primer pairs from TSH1188 (a resistant genotype) and Catongo (a susceptible genotype) ESTs were designed
and screened for polymorphism analysis. Eleven were polymorphic, with an average of 3.81 alleles per locus and a total of
42 alleles. The satellite markers were tested on 21 cacao accessions and two bulked DNAs generated from 6 resistant and 6
susceptible plants from a segregating F2 (SCA6 × ICS1) population for witches’ broom resistance. These results show that EST-derived microsatellites (short sequence
repeats, SSRs) in Theobroma cacao have many potential applications in linkage mapping and the planning of crosses. 相似文献
12.
Gene transferability from transgenic Brassica napus L. to various subspecies and varieties of Brassica rapa 总被引:1,自引:0,他引:1
Ling Xiao Changming Lu Bing Zhang Huijie Bo Yuhua Wu Gang Wu Yinglong Cao Deyue Yu 《Transgenic research》2009,18(5):733-746
Gene transferability from transgenic rapeseed to various subspecies and varieties of Brassica rapa was assessed in this study. Artificial crossability was studied in 118 cultivars of 7 B. rapa subspecies and varieties with the transgenic rapeseed GT73 (Brassica napus) as the pollen donor. On average 5.7 seeds were obtained per pollination, with a range from 0.05 to 19.4. The heading type
of B. rapa L. showed significantly higher crossability than non-heading types of B. rapa. The spontaneous outcrossing rate between B. rapa (female) and the transgenic rapeseed Ms8 × Rf3 (B. napus) (male) ranged from 0.039 to 0.406%, with an average of 0.19%. The fertilization process and the development of the hybrid
seeds as shown by fluorescent staining techniques indicated that the number of adhered pollens on the stigma was reduced by
80%, the number of pollen tubes in the style was reduced by 2/3 and the fertilization time was delayed by over 20 h when pollinated
with the transgenic rapeseed Ms8 × Rf3 in comparison with the bud self-pollination of B. rapa as control. About 10–70% of the interspecific hybrid embryos were aborted in the course of development. Some seeds looked cracked in
mature pods, which showed germination abilities lower than 10%. The spontaneous outcrossing rates were much lower than the
artificial crossability, and their survival fitness of the interspecific hybrid was very low, indicating that it should be
possible to keep the adventitious presence of the off-plants under the allowed threshold, if proper measures are taken. 相似文献
13.
James W. Olmstead Audrey M. Sebolt Antonio Cabrera Suneth S. Sooriyapathirana Sue Hammar Gloria Iriarte Dechun Wang Charles Y. Chen Esther van der Knaap Amy F. Iezzoni 《Tree Genetics & Genomes》2008,4(4):897-910
Linkage maps of the sweet cherry cultivar ‘Emperor Francis’ (EF) and the wild forest cherry ‘New York 54’ (NY) were constructed
using primarily simple sequence repeat (SSR) markers and gene-derived markers with known positions on the Prunus reference map. The success rate for identifying SSR markers that could be placed on either the EF or NY maps was only 26%
due to two factors: a reduced transferability of other Prunus-species-derived markers and a low level of polymorphism in the mapping parents. To increase marker density, we developed
four cleaved amplified polymorphic sequence markers (CAPS), 19 derived CAPS markers, and four insertion–deletion markers for
cherry based on 101 Prunus expressed sequence tags. In addition, four gene-derived markers representing orthologs of a tomato vacuolar invertase and
fruit size gene and two sour cherry sorbitol transporters were developed. To complete the linkage analysis, 61 amplified fragment
length polymorphism and seven sequence-related amplified polymorphism markers were also used for map construction. This analysis
resulted in the expected eight linkage groups for both parents. The EF and NY maps were 711.1 cM and 565.8 cM, respectively,
with the average distance between markers of 4.94 cM and 6.22 cM. A total of 82 shared markers between the EF and NY maps
and the Prunus reference map showed that the majority of the marker orders were the same with the Prunus reference map suggesting that the cherry genome is colinear with that of the other diploid Prunus species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
Tree peony (Paeonia suffruticosa Andrews), a woody deciduous shrub, belongs to the section Moutan DC. in the genus of Paeonia of the Paeoniaceae family. To increase the efficiency of breeding, two EST-derived marker systems were developed based on
a tree peony expressed sequence tag (EST) database. Using target region amplification polymorphism (TRAP), 19 of 39 primer
pairs showed good amplification for 56 accessions with amplicons ranging from 120 to 3,000 bp long, among which 99.3% were
polymorphic. In contrast, 7 of 21 primer pairs demonstrated adequate amplification with clear bands for simple sequence repeats
(SSRs) developed from ESTs, and a total of 33 alleles were found in 56 accessions. The similarity matrices generated by TRAP
and EST-SSR markers were compared, and the Mantel test (r = 0.57778, P = 0.0020) showed a moderate correlation between the two types of molecular markers. TRAP markers were suitable for DNA fingerprinting
and EST-SSR markers were more appropriate for discriminating synonyms (the same cultivars with different names due to limited
information exchanged among different geographic areas). The two sets of EST-derived markers will be used further for genetic
linkage map construction and quantitative trait locus detection in tree peony. 相似文献
15.
Development and genetic mapping of SSR markers in foxtail millet [Setaria italica (L.) P. Beauv.] 总被引:2,自引:0,他引:2
Xiaoping Jia Zhongbao Zhang Yinghui Liu Chengwei Zhang Yunsu Shi Yanchun Song Tianyu Wang Yu Li 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(4):821-829
SSR markers are desirable markers in analysis of genetic diversity, quantitative trait loci mapping and gene locating. In
this study, SSR markers were developed from two genomic libraries enriched for (GA)n and (CA)n of foxtail millet [Setaria italica (L.) P. Beauv.], a crop of historical importance in China. A total of 100 SSR markers among the 193 primer pairs detected
polymorphism between two mapping parents of an F2 population, i.e. “B100” of cultivated S. italica and “A10” of wild S. viridis. Excluding 14 markers with unclear amplifications, and five markers unlinked with any linkage group, a foxtail millet SSR
linkage map was constructed by integrating 81 new developed SSR markers with 20 RFLP anchored markers. The 81 SSRs covered
nine chromosomes of foxtail millet. The length of the map was 1,654 cM, with an average interval distance between markers
of 16.4 cM. The 81 SSR markers were not evenly distributed throughout the nine chromosomes, with Ch.8 harbouring the least
(3 markers) and Ch.9 harbouring the most (18 markers). To verify the usefulness of the SSR markers developed, 37 SSR markers
were randomly chosen to analyze genetic diversity of 40 foxtail millet accessions. Totally 228 alleles were detected, with
an average 6.16 alleles per locus. Polymorphism information content (PIC) value for each locus ranged from 0.413 to 0.847,
with an average of 0.697. A positive correlation between PIC and number of alleles and between PIC and number of repeat unit
were found [0.802 and 0.429, respectively (P < 0.01)]. UPGMA analysis revealed that the 40 foxtail millet cultivars could be grouped into five clusters in which the landraces’
grouping was largely consistent with ecotypes while the breeding varieties from different provinces in China tended to be
grouped together.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
16.
The functional male sterility controlled by ps gene proved to be a useful tool in hybrid tomato varieties breeding in Poland. The climat conditions such as excessive temperature
and high humidity have a bad effect on the expression and stability of functional male sterility. Using the RAPD methods we
have identified two RAPD markers linked to the ps gene. The markers OPW 131230 and OPAX 10780 were generated by 5′CACAGCGACA 3′ and 5′CCAGGCTGAC 3′ decamers respectively in F2 population of combination 24/29 × G-1. 相似文献
17.
Cai Xingxing Liu Jing Qiu Yinqiu Zhao Wei Song Zhiping Lu Baorong 《Frontiers of Biology in China》2007,2(3):291-296
DNA polymorphisms from nucleotide insertion/deletions (InDels) in genomic sequences are the basis for developing InDel molecular
markers. To validate the InDel primer pairs on the basis of the comparative genomic study on DNA sequences between an Indica rice 93-11 and a Japonica rice Nipponbare for identifying Indica and Japonica rice varieties and studying wild Oryza species, we studied 49 Indica, 43 Japonica, and 24 wild rice accessions collected from ten Asian countries using 45 InDel primer pairs. Results indicated that of the
45 InDel primer pairs, 41 can accurately identify Indica and Japonica rice varieties with a reliability of over 80%. The scatter plotting data of the principal component analysis (PCA) indicated
that: (i) the InDel primer pairs can easily distinguish Indica from Japonica rice varieties, in addition to revealing their genetic differentiation; (ii) the AA-genome wild rice species showed a relatively
close genetic relationship with the Indica rice varieties; and (iii) the non-AA genome wild rice species did not show evident differentiation into the Indica and Japonica types. It is concluded from the study that most of the InDel primer pairs obtained from DNA sequences of 93-11 and Nipponbare
can be used for identifying Indica and Japonica rice varieties, and for studying genetic relationships of wild rice species, particularly in terms of the Indica-Japonica differentiation.
Translated from Journal of Fudan University (Natural Science), 2006, 45(3): 309–315 [译自: 复旦学报(自然科学版)] 相似文献
18.
Ethidium monoazide bromide (EMA) treatment of pure culture and environmental waters at low concentrations (1.0–7.5 μg/ml)
indicated effective enumeration of viable and viable but nonculturable Escherichia coli in pure cultures, creek waters, and secondary activated sludge effluent samples by quantitative polymerase chain reaction
(qPCR) amplification of the uidA and fliC gene targets at turbidity values <10 NTU. However, EMA treatment was not effective in primary clarifier and secondary trickling
filter effluents where turbidities were ≥10 NTU. In viable pure cultures, rapidly dividing and senescent cells were most affected
by increasing EMA concentrations. Amplification of heat-killed pure bacterial cultures decreased 4 to 6 logs depending on
EMA concentration and culture age. The greatest difference was observed in 5-h cultures using 7.5 μg/ml EMA. Turbidity (≥100
NTU) in environmental samples inhibited EMA effectiveness on viability discrimination. Enumeration of E. coli in certain wastewaters using EMA-qPCR was similar to culture suggesting that EMA treatment could be incorporated into qPCR
assays for the quantification of viable bacteria increasing assay time no more than 30 min. Our results indicate that EMA
can be used in routine qPCR assays, but optimum conditions for exposure must be identified for each sample type due to sample
matrix effects such as turbidity. 相似文献
19.
Cuiping Yuan Guoan Zhou Yinghui Li Kejing Wang Zhi Wang Xianghua Li Ruzhen Chang Lijuan Qiu 《Molecular breeding : new strategies in plant improvement》2008,22(4):593-602
Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is the most important pathogen in soybean production worldwide and causes substantial yield losses. An apparent
narrow genetic base of SCN resistance was observed in current elite soybean cultivars, and searching for novel SCN resistance
genes as well as novel resistance sources rather than focusing on the two important genes rhg1 and Rhg4 has become another major objective in soybean research. In the present paper we report a 1,477 bp Hs1
pro-1
homolog, named GmHs1
pro-1
. This gene was cloned from soybean variety Wenfeng 7 based on information for Hs1
pro-1
, a beet cyst nematode resistance gene in sugar beet. It has two domains, Hs1pro-1_N and Hs1pro-1_C, both of which are believed
to confer resistance to nematodes. Of the 1,477 bp sequence in GmHs1
pro-1
, an open reading frame of 1,314 bp, encoding a protein with 437 amino acids, was flanked by a 5′-untranslated region of 27 bp
and a 3′-untranslated region of 135 bp. Fourteen single-nucleotide polymorphisms (SNPs) were observed in 44 soybean accessions
including 23 wild soybeans, 8 landraces, and 13 soybean varieties (or lines), among which 5 in wild soybeans and 3 in landrace
accessions were unique. Sequence diversity analysis on the 44 soybean accessions showed π = 0.00168 and θ = 0.00218 for GmHs1
pro-1
; landraces had the highest diversity, followed by wild soybeans, with varieties (or lines) having the lowest. Although we
did not detect a significant effect of selection on GmHs1
pro-1
in the three populations, sequence diversity, unique SNPs, and phylogenetic analysis indicated a slight domestication bottleneck
and an intensive selection bottleneck. High sequence diversity, more unique SNPs, and broader representation across the phylogenetic
tree in wild soybeans and landraces indicated that wild collections and landrace accessions are invaluable germplasm for broadening
the genetic base of elite soybean varieties resistant to SCN.
C. Yuan and G. Zhou contributed to this paper equally. 相似文献
20.
Ribitsch D Karl W Wehrschütz-Sigl E Tutz S Remler P Weber HJ Gruber K Stehr R Bessler C Hoven N Sauter K Maurer KH Schwab H 《Applied microbiology and biotechnology》2009,81(5):875-886
In the course of a microbial screening of soil samples for new oxidases, different enrichment strategies were carried out.
With choline as the only carbon source, a microorganism was isolated and identified as Arthrobacter nicotianae. From this strain, a gene coding for a choline oxidase was isolated from chromosomal DNA. This gene named codA was cloned in Escherichia coli BL21-Gold and the protein (An_CodA) heterologously overexpressed as a soluble intracellular protein of 59.1 kDa. Basic biochemical characterization of
purified protein revealed a pH optimum of 7.4 and activity over a broad temperature range (15–70 °C). Specific activities
were determined toward choline chloride (4.70 ± 0.12 U/mg) and the synthetic analogs bis(2-hydroxyethyl)-dimethylammonium
chloride (0.05 ± 0.45 × 10–2 U/mg) and tris-(2-hydroxyethyl)-methylammonium methylsulfate (0.01 ± 0.12 × 10–2 U/mg). With increasing number of oxidizable groups, a significant decrease in activity was noted. Determination of kinetic
parameters in atmorspheric oxygen resulted in K
M = 1.51 ± 0.09 mM and V
max = 42.73 ± 0.42 mU/min for choline chloride and K
M = 4.77 ± 0.76 mM and V
max = 48.40 ± 2.88 mU/min for the reaction intermediate betaine aldehyde respectively. Nuclear magnetic resonance spectroscopic
analysis of the products formed during the enzyme reaction with choline chloride showed that in vitro the intermediate betaine
aldehyde exists also free in solution. 相似文献