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1.
Linkage analysis in tetraploid potato and association of markers with quantitative resistance to late blight ( Phytophthora infestans ) 总被引:5,自引:0,他引:5
R. C. Meyer D. Milbourne C. A. Hackett J. E. Bradshaw J. W. McNichol R. Waugh 《Molecular & general genetics : MGG》1998,259(2):150-160
We have constructed a partial linkage map in tetraploid potato which integrates simplex, duplex and double-simplex AFLP markers.
The map consists of 231 maternal and 106 paternal markers with total map lengths of 990.9 cM and 484.6 cM. The longer of the
two cumulative map lengths represents approximately 25% coverage of the genome. In tetraploids, much of the polymorphism between
parental clones is masked by `dosage' which significantly reduces the number of individual markers that can be scored in a
population. Consequently, the major advantage of using AFLPs – their high multiplex ratio – is reduced to the point where
the use of alternative multi-allelic marker types would be significantly more efficient. The segregation data and map information
have been used in a QTL analysis of late blight resistance, and a multi-allelic locus at the proximal end of chromosome VIII
has been identified which contributes significantly to the expression of resistance. No late blight resistance genes or QTLs
have previously been mapped to this location.
Received: 1 October 1997 / Accepted: 18 March 1998 相似文献
2.
The present meta-analysis examined the efficacy of animal-assisted psychotherapy for individuals who have experienced trauma. Eight studies quantitatively assessed the treatment effects of involvement in animal-assisted psychotherapy. A random effects model was used to aggregate each study into an overall effect size. Eight effect sizes were included in the pre-versus post-comparison analysis. The results indicate a large effect size (Hedge’s g = 0.86, p < 0.001, 95% CI [.53, 1.18]). Two effect sizes were included in the treatment versus control comparison analysis. The results indicated a small to moderate effect size (g = 0.46, p = 0.03, 95% CI [0.04, 0.06]). Limited moderator analyses were able to be conducted due to lack of consistent reporting across studies. Place of study and percentage of female participants in the treatment group were found to statistically moderate the effect of animal-assisted psychotherapy. The results indicate that animal-assisted therapy is an efficacious treatment for trauma. 相似文献
3.
Melanie Febrer Foo Cheung Christopher D Town Steven B Cannon Nevin D Young Michael T Abberton Glyn Jenkins Dan Milbourne 《Génome》2007,50(4):412-421
White clover (Trifolium repens L.) is a forage legume widely used in combination with grass in pastures because of its ability to fix nitrogen. We have constructed a bacterial artificial chromosome (BAC) library of an advanced breeding line of white clover. The library contains 37 248 clones with an average insert size of approximately 85 kb, representing an approximate 3-fold coverage of the white clover genome based on an estimated genome size of 960 Mb. The BAC library was pooled and screened by polymerase chain reaction (PCR) amplification using both white clover microsatellites and PCR-based markers derived from Medicago truncatula, resulting in an average of 6 hits per marker; this supports the estimated 3-fold genome coverage in this allotetraploid species. PCR-based screening of 766 clones with a multiplex set of chloroplast primers showed that only 0.5% of BAC clones contained chloroplast-derived inserts. The library was further evaluated by sequencing both ends of 724 of the clover BACs. These were analysed with respect to their sequence content and their homology to the contents of a range of plant gene, expressed sequence tag, and repeat element databases. Forty-three microsatellites were discovered in the BAC-end sequences (BESs) and investigated as potential genetic markers in white clover. The BESs were also compared with the partially sequenced genome of the model legume M. truncatula with the specific intention of identifying putative comparative-tile BACs, which represent potential regions of microsynteny between the 2 species; 14 such BACs were discovered. The results suggest that a large-scale BAC-end sequencing strategy has the potential to anchor a significant proportion of the genome of white clover onto the gene-space sequence of M. truncatula. 相似文献
4.
Computational and experimental characterization of physically clustered simple sequence repeats in plants 总被引:68,自引:0,他引:68
The type and frequency of simple sequence repeats (SSRs) in plant genomes was investigated using the expanding quantity of DNA sequence data deposited in public databases. In Arabidopsis, 306 genomic DNA sequences longer than 10 kb and 36,199 EST sequences were searched for all possible mono- to pentanucleotide repeats. The average frequency of SSRs was one every 6.04 kb in genomic DNA, decreasing to one every 14 kb in ESTs. SSR frequency and type differed between coding, intronic, and intergenic DNA. Similar frequencies were found in other plant species. On the basis of these findings, an approach is proposed and demonstrated for the targeted isolation of single or multiple, physically clustered SSRs linked to any gene that has been mapped using low-copy DNA-based markers. The approach involves sample sequencing a small number of subclones of selected randomly sheared large insert DNA clones (e.g., BACs). It is shown to be both feasible and practicable, given the probability of fortuitously sequencing through an SSR. The approach is demonstrated in barley where sample sequencing 34 subclones of a single BAC selected by hybridization to the Big1 gene revealed three SSRs. These allowed Big1 to be located at the top of barley linkage group 6HS. 相似文献
5.
Nora M. Casey Dan Milbourne Susanne Barth Melanie Febrer Glyn Jenkins Michael T. Abberton Charlotte Jones Daniel Thorogood 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):567-576
White clover (Trifolium repens L.) is a forage legume of considerable economic importance in temperate agricultural systems. It has a strong self-incompatibility
system. The molecular basis of self-incompatibility in T. repens is unknown, but it is under the control of a single locus, which is expressed gametophytically. To locate the self-incompatibility
locus (S locus) in T. repens, we carried out cross-pollination experiments in an F1 mapping population and constructed a genetic linkage map using amplified fragment length polymorphism and simple sequence
repeat markers. As the first step in a map-based cloning strategy, we locate for the first time the S locus in T. repens on a genetic linkage map, on the homoeologous linkage group pair 1 (E), which is broadly syntenic to Medicago truncatula L. chromosome 1. On the basis of this syntenic relationship, the possibility that the S locus may or may not possess an S-RNase gene is discussed. 相似文献
6.
Molla F. Mengist Sheila Alves Denis Griffin Joanne Creedon Mike J. McLaughlin Peter W. Jones Dan Milbourne 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(4):929-945
Key message
Cd is a toxic metal, whilst Zn is an essential for plant and human health. Both can accumulate in potato tubers. We examine the genetic control of this process.Abstract
The aim of this study was to map quantitative trait loci (QTLs) influencing tuber concentrations of cadmium (Cd) and zinc (Zn). We developed a segregating population comprising 188 F1 progeny derived from crossing two tetraploid cultivars exhibiting divergent tuber-Cd-accumulation phenotypes. These progeny were genotyped using the SolCap 8303 SNP array, and evaluated for Cd, Zn, and maturity-related traits. Linkage and QTL mapping were performed using TetraploidSNPMap software, which incorporates all allele dosage information. The final genetic map comprised 3755 SNP markers with average marker density of 2.94 per cM. Tuber-Cd and Zn concentrations were measured in the segregating population over 2 years. QTL mapping identified four loci for tuber-Cd concentration on chromosomes 3, 5, 6, and 7, which explained genetic variance ranging from 5 to 33%, and five loci for tuber-Zn concentration on chromosome 1, 3, 5, and, 6 explaining from 5 to 38% of genetic variance. Among the QTL identified for tuber-Cd concentration, three loci coincided with tuber-Zn concentration. The largest effect QTL for both tuber-Cd and Zn concentration coincided with the maturity locus on chromosome 5 where earliness was associated with increased tuber concentration of both metals. Coincident minor-effect QTL for Cd and Zn sharing the same direction of effect was also found on chromosomes 3 and 6, and these were unrelated to maturity The results indicate partially overlapping genetic control of tuber-Cd and Zn concentration in the cross, involving both maturity-related and non-maturity-related mechanisms.7.
8.
Potato in the age of biotechnology 总被引:3,自引:0,他引:3
Mullins E Milbourne D Petti C Doyle-Prestwich BM Meade C 《Trends in plant science》2006,11(5):254-260
Biotechnology-based tools are now widely used to enhance and expand the traditional remit of potato in food production. By modifying its functionality, the capacity of the potato to produce, for example, therapeutic or industrial compounds is now a reality, and its ability to resist disease can also be radically improved. Two developments have been crucial to expanding the role of potato: the recent advances in the fields of structural and functional potato genomics and the ability to integrate genes of interest into the potato genome. In this review we discuss how both developments have diversified the remit of this crop. 相似文献
9.
Homology model of human retinoic acid metabolising enzyme cytochrome P450 26A1 (CYP26A1): active site architecture and ligand binding 总被引:2,自引:0,他引:2
Gomaa MS Yee SW Milbourne CE Barbera MC Simons C Brancale A 《Journal of enzyme inhibition and medicinal chemistry》2006,21(4):361-369
Homology models of cytochrome P450 RA1 (CYP26A1) were constructed using three human P450 structures, CYP2C8, CYP2C9 and CYP3A4 as templates for the model building. Using MOE software the lowest energy CYP26A1 model was then assessed for stereochemical quality and side chain environment. Further active site optimisation of the CYP26A1 model built using the CYP3A4 template was performed by molecular dynamics to generate a final CYP26A1 model. The natural substrate, all-trans-retinoic acid (atRA), and inhibitor R 15866, were docked into the model allowing further validation of the active site architecture. Using the docking studies structurally and functionally important residues were identified with subsequent characterisation of secondary structure. Multiple hydrophobic interactions, including the side chains of TRP112, PHE299, PHE222, PHE84, PHE374 and PRO371, are important for binding of atRA and R115866. Additional hydrogen bonding interactions were noted as follows: atRA-- C==O of the atRA carboxylate group and ARG86; R115866--benzothiazole nitrogen and the backbone NH of SER115. 相似文献
10.
Molla F. Mengist Dan Milbourne Sheila Alves Mike J. McLaughlin Peter W. Jones Denis Griffin 《Plant and Soil》2018,427(1-2):139-148