共查询到20条相似文献,搜索用时 15 毫秒
1.
L.W.D. van Raamsdonk M. Vrielink-van Ginkel C. Kik 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(7):1000-1009
Amplified fragment length polymorphisms (AFLPs) for assessing nuclear DNA diversity have been used for the reconstruction
of the phylogeny and evolution of several sections of Allium subgenus Rhizirideum. A dataset of 355 characters for 33 accessions belonging to 20 species has been compiled. The band-sharing of five interspecific
hybrids and of an F2 population between Allium cepa and Allium roylei with their parents indicated a heterozygosity level between 6 and 14%, which allows the use of dominant markers such as AFLPs
for phylogeny reconstruction. A majority rule consensus tree based on 56 most-parsimonius trees (CI = 0.528) revealed a separate
clade for each of the sections, Cepa, Rhizirideum and Schoenoprasum, and one clade combining the sections Oreiprason and Petroprason. An unweighted pair group mean average (UPGMA)-based dendrogram showed the same subdivision. The trees and the ’Hybrid Distance’
approach both supported the assumption of a hybrid origin for A. roylei with considerable subsequent secondary evolution. The establishment of three alliances in the section Cepa and the close relationship of sections Oreiprason and Petroprason are now confirmed. The predictions of the Soybean domestication scenario, i.e. selection of a crop from one progenitor with
subsequent narrowing of the genetic diversity of the crop, which applies to the cultigens A. cepa and Allium fistulosum, is supported by the Hybrid Distance approach.
Received: 23 August 1999 / Accepted: 14 September 1999 相似文献
2.
The use of microsatellites for germplasm management in a Portuguese grapevine collection 总被引:2,自引:0,他引:2
M. S. Lopes K. M. Sefc E. Eiras Dias H. Steinkellner M. Laimer Câmara Machado A. Câmara Machado 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(3-4):733-739
To initiate the characterization of the Portuguese grapevine genepool, we have genotyped 49 Portuguese grapevine cultivars at 11 microsatellite loci. The markers proved to be informative in the Portuguese cultivars, with expected heterozygosity ranging from 0.67 to 0.84. At most loci, an excess of heterozygous individuals was observed, while the deficiency of heterozygotes at 1 locus (VVMD6) indicated the presence of null alleles. On the basis of the microsatellite allele data several previously assumed synonyms were verified: (1) ’Fernão Pires’=’Maria Gomes’, (2) ’Moscatel de Setúbal’=’Muscat of Alexandria’, (3) ’Boal Cachudo’=’Boal da Madeira’=’Malvasia Fina’, (4) ’Síria’=’Crato Branco’= ’Roupeiro’ and (5) ’Periquita’=’Castelão Francês’=’João de Santarém’=’Trincadeira’. Although the three varieties ’Verdelho da Madeira’, ’Verdelho dos Açores’, and ’Verdelho roxo’ are regarded by the Lista Nacional de Sinónimos as distinct cultivars, they displayed identical SSR profiles at 17 loci and appear to represent types of 1 single cultivar. The genetic profiles of all 49 cultivars were searched for possible parent-offspring groups. The data obtained revealed the descendence of ’Boal Ratinho’ from ’Malvasia Fina’ and ’Síria’. 相似文献
3.
G. J. Bryan A. J. Collins P. Stephenson A. Orry J. B. Smith M. D. Gale 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(5):557-563
The development of large panels of simple-to-analyse genetic markers for tagging agronomically important genes and diversity
studies in hexaploid bread wheat is an important goal in applied cereal genetic research. We have isolated and sequenced over
200 clones containing microsatellites from the wheat genome and have tested 153 primer pairs for genetic polymorphism using
a panel of ten wheat varieties, including the parents of our main mapping cross. A subset comprising 49 primer pairs detects
76 loci, of which 74 can be unequivocably allocated to one of the wheat chromosomes. A relatively low frequency of the loci
detected are from the D genome, and these loci show less polymorphism than those from the A and B genomes. Generally, the
microsatellites show high levels of genetic polymorphism and an average of 3.5 alleles per locus with an average polymorphism
information content (PIC), value of 0.51. The observed levels of polymorphism are positively correlated with the length of
the microsatellite repeats. A high proportion, approximately two-thirds, of primer pairs designed to detect simple sequence
repeat (SSR) variation in wheat do not generate the expected amplification products and, more significantly, often generate
unresolvable PCR products. In general, our results agree closely with those obtained from other recent studies using microsatellites
in plants.
Received: 19 March 1996 / Accepted: 28 June 1996 相似文献
4.
M. I. Buteler R. L. Jarret D. R. LaBonte 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(1-2):123-132
The objectives of the present study were to evaluate the inheritance and nucleotide sequence profiles of microsatellite genetic
markers in hexaploid sweetpotato [Ipomoea batatas (L.) Lam.] and its putative tetraploid and diploid ancestors, and to test possible microsatellite mutation mechanisms in
polyploids by direct sequencing of alleles. Sixty three microsatellite loci were isolated from genomic libraries of I. batatas and sequenced. PCR primers were designed and used to characterize microsatellite loci in two hexaploid I. batatas populations, a tetraploid Ipomoea trifida population, and a diploid I. trifida population. Nine out of the sixty three primer pairs tested yielded a clearly discernible, heritable banding pattern; five
showed Mendelian segregation. All other primer pairs produced either smeared banding patterns, which could not be scored,
or no bands at all in I. batatas. All of the primers which produced discernible banding patterns from I. batatas also amplified products of similar size in tetraploid and diploid I. trifida accessions. The sequence analysis of several alleles in the three species showed differences due to mutations in the repeat
regions consistent with small differences in the repeat number. However, in some cases insertions/deletions and base substitutions
in the microsatellite flanking regions were responsible for polymorphisms in both polyploid and diploid species. These results
provide strong empirical evidence that complex genetic mechanisms are responsible for SSR allelic variation in Ipomoea. Four I. batatas microsatellite loci showed polysomic segregation fitting tetraploid segregation ratios. To our knowledge this is the first
report of segregation ratios for microsatellites markers in polyploids.
Received: 4 January 1999 / Accepted: 4 January 1999 相似文献
5.
Diversity of microsatellites derived from genomic libraries and GenBank sequences in rice (Oryza sativa L.) 总被引:28,自引:14,他引:14
Y. G. Cho T. Ishii S. Temnykh X. Chen L. Lipovich S. R. McCouch W. D. Park N. Ayres S. Cartinhour 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(5):713-722
The growing number of rice microsatellite markers warrants a comprehensive comparison of allelic variability between the markers
developed using different methods, with various sequence repeat motifs, and from coding and non-coding portions of the genome.
We have performed such a comparison over a set of 323 microsatellite markers; 194 were derived from genomic library screening
and 129 were derived from the analysis of rice-expressed sequence tags (ESTs) available in public DNA databases. We have evaluated
the frequency of polymorphism between parental pairs of six inter- subspecific crosses and one inter-specific cross widely
used for mapping in rice. Microsatellites derived from genomic libraries detected a higher level of polymorphism than those
derived from ESTs contained in the GenBank database (83.8% versus 54.0%). Similarly, the other measures of genetic variability
[the number of alleles per locus, polymorphism information content (PIC), and allele size ranges] were all higher in genomic
library-derived microsatellites than in their EST-database counterparts. The highest overall degree of genetic diversity was
seen in GA-containing microsatellites of genomic library origin, while the most conserved markers contained CCG- or CAG-trinucleotide
motifs and were developed from GenBank sequences. Preferential location of specific motifs in coding versus non-coding regions
of known genes was related to observed levels of microsatellite diversity. A strong positive correlation was observed between
the maximum length of a microsatellite motif and the standard deviation of the molecular-weight of amplified fragments. The
reliability of molecular weight standard deviation (SDmw) as an indicator of genetic variability of microsatellite loci is
discussed.
Received: 5 May 1999 / Accepted: 16 August 1999 相似文献
6.
An evaluation of the utility of SSR loci as molecular markers in maize (Zea mays L.): comparisons with data from RFLPS and pedigree 总被引:8,自引:0,他引:8
J. S. C. Smith E. C. L. Chin H. Shu O. S. Smith S. J. Wall M. L. Senior S. E. Mitchell S. Kresovich J. Ziegle 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(1-2):163-173
The utility of 131 simple sequence repeat (SSR) loci to characterize and identify maize inbred lines, validate pedigree,
and show associations among inbred lines was evaluated using a set of 58 inbred lines and four hybrids. Thirteen sets of inbred
parent-progeny triplet pedigrees together with four hybrids and their parental lines were used to quantify incidences of scoring
that departed from expectations based upon simple Mendelian inheritance. Results were compared to those obtained using 80
restriction fragment length polymorphism (RFLP) probes. Over all inbred triplets, 2.2% of SSRs and 3.6% of RFLP loci resulted
in profiles that were scored as having segregated in a non-Mendelian fashion. Polymorphic index content (PIC, a measure of
discrimination ability) values ranged from 0.06 to 0.91 for SSRs and from 0.10 to 0.84 for RFLPs. Mean values for PIC for
SSRs and RFLPs were similar, approximately 0.62. However, PIC values for nine SSRs exceeded the maximum PIC for RFLPs. Di-repeats
gave the highest mean PIC scores for SSRs but this class of repeats can result in “stutter” bands that complicate accurate
genotyping. Associations among inbreds were similar for SSR and RFLP data, closely approximating expectations from known pedigrees.
SSR technology presents the potential advantages of reliability, reproducibility, discrimination, standardization and cost
effectiveness over RFLPs. SSR profiles can be readily interpreted in terms of alleles at mapped loci across a broad range
of maize germ plasm. Consequently, SSRs represent the optimum approach for the identification and pedigree validation of maize
genotypes compared to other currently available methods.
Received: 15 January 1997 / Accepted: 28 February 1997 相似文献
7.
K. Loridon B. Cournoyer C. Goubely A. Depeiges G. Picard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(4):591-604
The objective of this work was to assess the degree of trinucleotide microsatellite length polymorphism in the selfing species
Arabidopsis thaliana. PCR amplifications of 12 microsatellite loci among 49 natural populations revealed between one to eight length variants
(alleles) for each locus. The average number of alleles per locus was four and the average genetic diversity index was 0.43.
Divergence between length variants was investigated at the nucleotide level. Several observations emerge from the sequence
data: (1) for most loci, length polymorphism results only from variations in the number of trinucleotide repeats; (2) for
a few others, some variability was noted in the flanking sequences; (3) for compound and interrupted loci containing two arrays
of trinucleotide repeats, length variations preferentially affect the longest one. Five of the Arabidopsis thaliana accessions were clearly composed of two sublines. In 2 other accessions, some heterozygous individual plants, probably resulting
from recent outcrosses, were found. A phylogenetic tree constructed on the basis of trinucleotide microsatellite allelic diversity
shows that genetic relationships among the accessions are not correlated with their geographic origin.
Received: 4 November 1997 / Accepted: 3 March 1998 相似文献
8.
Polymorphic simple sequence repeat markers in chloroplast genomes of Solanaceous plants 总被引:13,自引:0,他引:13
G. J. Bryan J. McNicoll G. Ramsay R. C. Meyer W. S. De Jong 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(5):859-867
PCR-based markers were developed from mononucleotide simple-sequence repeats in the chloroplast genome of Nicotiana tabacum and applied to the analysis of genetic diversity. These markers were found to detect high levels of polymorphism at three
taxonomic levels in Solanaceous plants. Of 36 chloroplast loci examined, 26 show some degree of polymorphism among potato
accessions. Among a set of 30 tetraploid potato cultivars it is apparent that a single chloroplast haplotype is prevalent,
presumably a result of the widespread use as a female parent of the imported US cultivar Rough Purple Chili in the latter
half of the 19th century. Nonetheless, there is considerable chloroplast diversity in the cultivated potato, and it is clear
that a large proportion of this variability has arisen through the use of wild or primitive cultivated species of potato in
introgression programmes. This variability should be used in future breeding programmes. An examination of single accessions
from 24 potato species, as well as representatives from tobacco and other members of the Solanaceae, reveals high levels of
inter-specific chloroplast DNA variation. These data, and the ease of use and potential for multiplexing of these markers,
suggest that cpSSRs will be of great utility in population genetics, germplasm management, evolutionary and phylogenetic studies
as well as in, the analysis of material from introgression and somatic-fusion experiments. Interestingly, the polymorphism
arising from one of the more-polymorphic chloroplast loci examined, does not originate solely from the SSR, and is due to
variation in the copy number of two tandemly arrayed sequence elements.
Received: 15 December 1998 / Accepted: 9 February 1999 相似文献
9.
Cipriani G Marrazzo MT Marconi R Cimato A Testolin R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,104(2-3):223-228
We have isolated and sequenced 52 microsatellites or simple sequence repeats (SSRs) from nearly 60 positive clones obtained
from two ’Frantoio’ olive genomic libraries enriched in (AC/GT) and (AG/CT) repeats, respectively. The repeat-containing fragments
obtained from genomic DNA restricted with Tsp509I were separated using a biotinylated probe bound to streptavidin-coated paramagnetic beads. Fragments were then cloned into
lambda ZAPII vector and sequenced. Thirty of the 36 primer pairs which gave correct re-amplification in the source genome
were used to assay the polymorphism of 12 olive cultivars, namely four well-known cultivars (’Coratina’, ’Frantoio’, ’Leccino’,
’Pendolino’) and eight ancient cultivars grown locally near Lake Garda (’Casaliva’, ’Favarol’, ’Fort’, ’Grignan’, ’Less’,
’Raza’, ’Rossanel’, ’Trep’). The local cultivars were each re- presented by two to four long-lived individuals. The analysis
was carried out using 33P-labelled primers and 6% polyacrylamide sequencing gels. All except two microsatellites showed polymorphism, the number of
alleles varying from 1 to 5. The average genetic diversity (H) was 0.55. The power of discrimination (PD) was 0.60. All cultivars, including the local ones, were easily separated from each other. Variations in the SSR pattern
were observed among individual plants of the same cultivar in four out of the eight local cultivars analysed. Several primer
pairs (17%) amplified more than one locus.
Received: 23 March 2001 / Accepted 17 May 2001 相似文献
10.
《Fungal Ecology》2016
Clade 2 of the Fusarium solani species complex contains plant pathogens including Fusarium virguliforme and closely related species Fusarium brasiliense, Fusarium crassistipitatum, Fusarium tucumaniae, which are the primary causal agents of soybean sudden death syndrome (SDS), a significant threat to soybean production. In this study, we developed microsatellite markers from a F. virguliforme genome sequence and applied them to a F. virguliforme population collection of 38 isolates from Michigan and four reference strains from other locations. Of the 225 detected microsatellite loci, 108 loci were suitable for primer design, and 12 of the microsatellite markers were determined to be highly polymorphic, amplifying on average 5.7 alleles per locus. Using these markers, F. virguliforme isolates were partitioned into three distinct clusters, but isolates were not grouped based on relatedness of sampling sites. In addition, 11 out of 12 markers were demonstrated to be highly transferrable to other closely related species. 相似文献
11.
The use of microsatellites for detecting DNA polymorphism, genotype identification and genetic diversity in wheat 总被引:35,自引:0,他引:35
M. Prasad R. K. Varshney J. K. Roy H. S. Balyan P. K. Gupta 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(3-4):584-592
A set of 20 wheat microsatellite markers was used with 55 elite wheat genotypes to examine their utility (1) in detecting
DNA polymorphism, (2)in the identifying genotypes and (3) in estimating genetic diversity among wheat genotypes. The 55 elite
genotypes of wheat used in this study originated in 29 countries representing six continents. A total of 155 alleles were
detected at 21 loci using the above microsatellite primer pairs (only 1 primer amplified 2 loci; all other primers amplified
1 locus each). Of the 20 primers amplifying 21 loci, 17 primers and their corresponding 18 loci were assigned to 13 different
chromosomes (6 chromosomes of the A genome, 5 chromosomes of the B genome and 2 chromosomes of the D genome). The number of
alleles per locus ranged from 1 to 13, with an average of 7.4 alleles per locus. The values of average polymorphic information
content (PIC) and the marker index (MI) for these markers were estimated to be 0.71 and 0.70, respectively. The (GT)n microsatellites were found to be the most polymorphic. The genetic similarity (GS) coefficient for all possible 1485 pairs
of genotypes ranged from 0.05 to 0.88 with an average of 0.23. The dendrogram, prepared on the basis of similarity matrix
using the UPGMA algorithm, delineated the above genotypes into two major clusters (I and II), each with two subclusters (Ia,
Ib and IIa, IIb). One of these subclusters (Ib) consisted of a solitary genotype (E3111) from Portugal, so that it was unique
and diverse with respect to all other genotypes belonging to cluster I and placed in subcluster Ia. Using a set of only 12
primer pairs, we were able to distinguish a maximum of 48 of the above 55 wheat genotypes. The results demonstrate the utility
of microsatellite markers for detecting polymorphism leading to genotype identification and for estimating genetic diversity.
Received: 15 May 1999 / Accepted: 27 July 1999 相似文献
12.
A low-density genetic map of onion reveals a role for tandem duplication in the evolution of an extremely large diploid genome 总被引:8,自引:0,他引:8
J. J. King J. M. Bradeen O. Bark J. A. McCallum M. J. Havey 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(1):52-62
The bulb onion, Allium cepa L., is a diploid (2n=2x=16) plant with a huge nuclear genome. Previous genetic and cytogenetic analyses have not supported
a polyploid origin for onion. We developed a low-density genetic map of morphological markers, randomly amplified polymorphic
DNAs (RAPD), and restriction fragment length polymorphisms (RFLP) as a tool for onion improvement and to study the genome
organization of onion. A mapping population of 58 F3 families was produced from a single F1 plant from the cross of two partially inbred lines (Brigham Yellow Globe 15-23 and Alisa Craig 43). Segregations were established
for restoration of male fertility in sterile cytoplasm, complementary light-red bulb color, 14 RAPDs, 110 RFLPs revealed by
90 anonymous cDNA clones, and 2 RFLPs revealed by a cDNA clone of alliinase, the enzyme responsible for the characteristic
Allium flavors. Duplicated RFLP loci were detected by 21% of the clones, of which 53% were unlinked (>30 cM), 5% loosely linked
(10–30 cM), and 42% tightly linked (<10 cM). This duplication frequency is less than that reported for paleopolyploids but
higher than for diploid species. We observed 40% dominant RFLPs, the highest yet reported among plants. Among duplicated RFLP
loci, 19% segregated as two loci each with two codominant alleles, 52% segregated as one locus with codominant alleles and
one locus with only a dominant fragment, and 29% segregated as two loci with only dominant fragments. We sequenced cDNAs detecting
duplicated RFLPs; 63% showed homology to known gene families (e.g., chlorophyll binding proteins, ubiquitin, or RuBISCO),
and 37% were unique clones showing significant homology to known genes of low-copy number or no homology to database sequences.
Duplicated RFLPs showing linkage could be due to retroviral-like sequences in adjacent coding regions or intrachromosomal,
as opposed to whole genome, duplications. Previous cytological analyses and this genetic map support intrachromosomal duplication
as a mechanism contributing to the huge onion genome.
Received: 3 July 1997 / Accepted: 8 August 1997 相似文献
13.
Isolation and characterization of microsatellites in trembling aspen (Populus tremuloides) 总被引:13,自引:0,他引:13
S. Dayanandan O. P. Rajora K. S. Bawa 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(6-7):950-956
We have identified, isolated, and characterized microsatellite/simple sequence repeat (SSR) loci in trembling aspen (Populus tremuloides) by screening partial genomic libraries. We have also examined the compatibility and use of the P. tremuloides SSR primers to resolve microsatellites in other Populus species. Fourteen microsatellites were identified from 1600 clones screened. The TC/AG microsatellites were the most abundant.
A total of 29 alleles were detected in 36 P. tremuloides individuals at the four SSR loci (two each of di- and tri-nucleotide repeats) characterized. The number of alleles at the
SSR loci ranged from 5 to 11, with an average of 7.25 alleles per locus, and the observed heterozygosity ranged from 0.19
to 0.82, with a mean of 0.46 per locus. Although the highest polymorphism was observed for a dinucleotide SSR locus, the trinucleotide
SSR loci showed substantial polymorphism. There were 34 unique multilocus genotypes among the 36 P. tremuloides individuals examined, and 89% of the individuals had unique multilocus genotypes. Two pairs of SSR primers were successful
in PCR, amplifying genomic DNA and resolving microsatellites of comparable size from Populus deltoides, P. nigra, P.×canadensis, and P. maximowiczii. The microsatellite DNA markers developed could be used for clonal fingerprinting, certification of controlled crosses, genome
mapping, marker-assisted early selection, genetic diversity assessments, and conservation and sustainable management of poplar
genetic resources.
Received: 14 November 1997 / Accepted: 17 November 1997 相似文献
14.
Assessment of genetic diversity within and among germplasm accessions in cultivated sorghum using microsatellite markers 总被引:6,自引:0,他引:6
Y. Djè M. Heuertz C. Lefèbvre X. Vekemans 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(6):918-925
Microsatellite markers are increasingly being used in crop plants to discriminate among genotypes and as tools in marker-assisted
selection. Here we evaluated the use of microsatellite markers to quantify the genetic diversity within as well as among accessions
sampled from the world germplasm collection of sorghum. Considerable variation was found at the five microsatellite loci analysed,
with an average number of alleles per locus equal to 2.4 within accessions and 19.2 in the overall sample of 25 accessions.
The collection of sorghum appeared highly structured genetically with about 70% of the total genetic diversity occurring among
accessions. However, differentiation among morphologically defined races of sorghum, or among geographic origins, accounted
for less than 15% of the total genetic diversity. Our results are in global agreement with those obtained previously with
allozyme markers. We were also able to show that microsatellite data are useful in identifying individual accessions with
a high relative contribution to the overall allelic diversity of the collection.
Received: 10 August 1999 / Accepted: 27 August 1999 相似文献
15.
Simple sequence repeats for the genetic analysis of apple 总被引:35,自引:0,他引:35
L. Gianfranceschi N. Seglias R. Tarchini M. Komjanc C. Gessler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(8):1069-1076
The development of highly informative markers, such as simple sequence repeats, for tagging genes controlling agronomic characters
is essential for apple breeding. Furthermore the use of these markers is fundamental both for variety identification and for
the characterisation and management of genetic resources. We have developed 16 reliable simple sequence repeat (SSR) markers
that amplify all alleles from a panel of 19 Malus x domestica (Borkh.) cultivars or breeding selections and from Malus floribunda 821. Those markers show a high level of genetic polymorphism, with on average 8.2 alleles per locus and an average heterozygosity
of 0.78. Due to this high level of polymorphism, it was possible using two selected SSRs to distinguish all cultivars except
Starking and Red Delicious. Ten of the markers we developed have been mapped on a RAPD linkage map, proving their Mendelian
segregation as well as their random distribution in the apple genome. Finally, we discuss the importance of using co-dominant
markers in outbreeding species.
Received: 8 October 1997 / Accepted: 9 December 1997 相似文献
16.
An in-silico analysis of simple sequence repeats (SSRs) in 30 species of tobamoviruses was done. SSRs (mono to hexa) were present with variant frequency across species. Compound microsatellites, primarily of variant motifs accounted for up to 11.43% of the SSRs. Motif duplications were observed for A, T, AT, and ACA repeats. (AG)–(TC) was the most prevalent SSR-couple. SSRs were differentially localized in the coding region with ~ 54% on the 128 kDa protein while 20.37% was exclusive to 186 kDa protein. Characterization of such variations is important for elucidating the origin, sequence variations, and structure of these widely used, but incompletely understood sequences. 相似文献
17.
Simple sequence repeats (SSRs) or microsatellites are known to exhibit ubiquitous across all kingdoms of life including viruses. However, imperfections in simple sequence repeats have been analyzed in genomes of human, Escherichia coli and Human Immunodeficiency virus. The assessment of compound microsatellites in plant viral genomes is yet to be studied. Potyviruses severely affect crop plant growth and reduce economic yield in diverse cropping systems worldwide. Hence, we analyze the nature and distribution of compound microsatellites present in complete genome of 45 potyvirus species. The results indicate that compound microsatellites accounted for about 0% to 15.15% of all microsatellites and have low complexity as compared to that of prokaryotic genomes. Overall, 14% of compound microsatellites were of similar motifs and such motif duplications were observed for CA, TA and AG repeats. Among all 45 potyvirus genomes analyzed, SSR couple (AG)-x-(AC) was found to be the most abundant one. Hence it is apparent that in contrast to eukaryotes, majority of compound microsatellites in potyviruses were composed of variant motifs. We also highlight the relative frequency of different classes of compound microsatellites as well as their patterns of distribution and correlate with biology of potyviruses. Further characterization of such variation is important for elucidating the origin, mutational processes, and structure of these widely used, but incompletely understood sequences. 相似文献
18.
Microsatellite DNA in Actinidia chinensis: isolation, characterisation, and homology in related species 总被引:5,自引:0,他引:5
W.-G. Huang G. Cipriani M. Morgante R. Testolin 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(8):1269-1278
We have isolated and sequenced 263 microsatellite-containing clones from two small insert libraries of Actinidia chinensis enriched for (AC/GT) and (AG/CT) repeats, respectively. Primer pairs were designed for 203 microsatellite loci and successfully
amplified from both plasmid and A. chinensis genomic DNA. In this paper we report the sequences of 40 primer pairs for which we have demonstrated Mendelian segregation
in the progeny from controlled crosses. The polymorphism of ten microsatellites of each type was evaluated in four diploid
and six tetraploid genotypes of A. chinensis. All microsatellites proved to be polymorphic, the number of alleles per locus detected in polyacrylamide sequencing gels
ranging from 9 to 17. The high degree of polymorphism in Actinidia renders these markers useful either for mapping in A. chinensis or for fingerprinting cultivars of both domesticated kiwifruit species (A. chinensis and A. deliciosa). While most primer pairs produced single amplification products, about 20% generated banding patterns consistent with the
amplification of two different loci. This supports the hypothesis that diploid species of Actinidia (2n=2x=58) are polyploid in origin with a basic chromosome number x=14/15 and that chromosome duplication may have occurred during the evolution of the genus. Finally, we have assayed the cross-species
transportability of primer pairs designed from A. chinensis sequences and have found extensive cross-species amplification within the genus Actinidia; 75% of primer pairs gave successful amplification in the eight species assayed (A. arguta, A. rufa, A. polygama, A. chrysantha, A. callosa, A. hemsleyana, A. eriantha, and A. deliciosa), which are representative of the four sections into which the genus is currently split.
Received: 14 February 1998 / Accepted: 26 May 1998 相似文献
19.
K. M. Sefc H. Steinkellner J. Glössl S. Kampfer F. Regner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):227-231
Microsatellites are ideal markers for revealing genetic relationships between individuals because of their co-dominant inheritance. In this study we determined the genetic profiles of 52 grapevine cultivars using 32 microsatellite markers. We were able to define the complex genetic relationship among nine European grapevine cultivars. None of these parent-offspring combinations were anticipated beforehand. The ancient cultivar Silvaner is shown to be an offspring from Traminer and Österreichisch Weiß. Rotgipfler originates from a cross between Traminer and Roter Veltliner, while Frühroter Veltliner originates from Roter Veltliner×Silvaner and Frühroter Veltliner× Portugieser gave rise to Jubiläumsrebe. A pedigree illustrating the putative crosses was reconstructed. 相似文献
20.
G. Cipriani G. Lot W.-G. Huang M. T. Marrazzo E. Peterlunger R. Testolin 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(1-2):65-72
We report the sequences of 17 primer pairs of microsatellite loci, which we have cloned and sequenced from two genomic libraries
of peach [Prunus persica (L) Batsch] ‘Redhaven’, enriched for AC/GT and AG/CT repeats respectively. For ten of these microsatellite loci we were able
to demonstrate Mendelian inheritance in a segregating back-cross population; the remainder did not segregate. The polymorphism
of the microsatellites was evaluated in a panel of ten peach genotypes, including true-to-type peaches, nectarines and one
canning-peach. Fifteen microsatellites (88%) were polymorphic showing 2–4 alleles each. The mean heterozygosity, averaged
over all loci, was 0.32 and significantly higher than that reported in the literature for isozymes and molecular markers,
such as RFLPs and RAPDs. We have also assayed the cross-species transportability and found that ten microsatellite (59%) gave
apparently correct amplification in all Prunus species surveyed, namely P. domestica (European plum), P. salicina (Japanese plum), P. armeniaca (apricot), P. dulcis (almond), P. persica var. vulgaris (peach), P. persica var. laevis (nectarine), P. avium (sweet cherry) and P. cerasus (sour cherry), with three of them also being amplified in Malus (apple). The remaining microsatellites gave less-extensive amplification. Because of their appreciable polymorphism and wide
cross-species transportability, most of these new markers can be integrated into the linkage maps which are currently being
constructed in peach, as well as in other stone fruit crops, such as almond, apricot, cherry and plum.
Received: 3 September 1998 / Accepted: 28 November 1998 相似文献