Displaying publications 1 - 20 of 66 in total

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  1. Zaki NM, Singh R, Rosli R, Ismail I
    Int J Mol Sci, 2012;13(4):4069-88.
    PMID: 22605966 DOI: 10.3390/ijms13044069
    Species-specific simple sequence repeat (SSR) markers are favored for genetic studies and marker-assisted selection (MAS) breeding for oil palm genetic improvement. This report characterizes 20 SSR markers from an Elaeis oleifera genomic library (gSSR). Characterization of the repeat type in 2000 sequences revealed a high percentage of di-nucleotides (63.6%), followed by tri-nucleotides (24.2%). Primer pairs were successfully designed for 394 of the E. oleifera gSSRs. Subsequent analysis showed the ability of the 20 selected E. oleifera gSSR markers to reveal genetic diversity in the genus Elaeis. The average Polymorphism Information Content (PIC) value for the SSRs was 0.402, with the tri-repeats showing the highest average PIC (0.626). Low values of observed heterozygosity (H(o)) (0.164) and highly positive fixation indices (F(is)) in the E. oleifera germplasm collection, compared to the E. guineensis, indicated an excess of homozygosity in E. oleifera. The transferability of the markers to closely related palms, Elaeis guineensis, Cocos nucifera and ornamental palms is also reported. Sequencing the amplicons of three selected E. oleifera gSSRs across both species and palm taxa revealed variations in the repeat-units. The study showed the potential of E. oleifera gSSR markers to reveal genetic diversity in the genus Elaeis. The markers are also a valuable genetic resource for studying E. oleifera and other genus in the Arecaceae family.
    Matched MeSH terms: DNA, Plant/genetics*
  2. Yu G, Hatta A, Periyannan S, Lagudah E, Wulff BBH
    Methods Mol Biol, 2017;1659:207-213.
    PMID: 28856653 DOI: 10.1007/978-1-4939-7249-4_18
    DNA is widely used in plant genetic and molecular biology studies. In this chapter, we describe how to extract DNA from wheat tissues. The tissue samples are ground to disrupt the cell wall. Then cetyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) is used to disrupt the cell and nuclear membranes to release the DNA into solution. A reducing agent, β-mercaptoethanol, is added to break the disulfide bonds between the cysteine residues and to help remove the tanins and polyphenols. A high concentration of salt is employed to remove polysaccharides. Ethylenediaminetetraacetic acid (EDTA) stops DNase activity by chelating the magnesium ions. The nucleic acid solution is extracted with chloroform-isoamyl alcohol (24:1) or 6 M ammonium acetate. The DNA in aqueous phase is precipated with ethanol or isopropanol, which makes DNA less hydrophilic in the presence of sodium ions (Na+).
    Matched MeSH terms: DNA, Plant/genetics; DNA, Plant/isolation & purification*
  3. Yeo FK, Wang Y, Vozabova T, Huneau C, Leroy P, Chalhoub B, et al.
    Theor Appl Genet, 2016 Feb;129(2):289-304.
    PMID: 26542283 DOI: 10.1007/s00122-015-2627-5
    Rphq2, a minor gene for partial resistance to Puccinia hordei , was physically mapped in a 188 kbp introgression with suppressed recombination between haplotypes of rphq2 and Rphq2 barley cultivars.
    Matched MeSH terms: DNA, Plant/genetics
  4. Yeo BPH, Foong LC, Tam SM, Lee V, Hwang SS
    Biochem Mol Biol Educ, 2018 01;46(1):47-53.
    PMID: 29131478 DOI: 10.1002/bmb.21089
    Structures and functions of protein motifs are widely included in many biology-based course syllabi. However, little emphasis is placed to link this knowledge to applications in biotechnology to enhance the learning experience. Here, the conserved motifs of nucleotide binding site-leucine rich repeats (NBS-LRR) proteins, successfully used for the isolation and characterization of many plant resistance gene analogues (RGAs), is featured in the development of a series of laboratory experiments using important molecular biology techniques. A set of previously isolated RGA sequences is used as the model for performing sequence alignment and visualising 3D protein structure using current bioinformatics programs (Clustal Omega and Argusdock software). A pair of established degenerate primer sequences is provided for the prediction of targeted amino acids sequences in the RGAs. Reverse transcription-polymerase chain reaction (RT-PCR) is used to amplify RGAs from total RNA samples extracted from the tropical wild relative of black pepper, Piper colubrinum (Piperaceae). This laboratory exercise enables students to correlate specific DNA sequences with respective amino acid codes and the interaction between conserved motifs of resistance genes with putatively targeted proteins. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(1):47-53, 2018.
    Matched MeSH terms: DNA, Plant/genetics*; DNA, Plant/isolation & purification*
  5. Yee W, Kumar JN, Muthusamy PD
    Indian J Microbiol, 2018 Mar;58(1):109-113.
    PMID: 29434405 DOI: 10.1007/s12088-017-0698-5
    2-mercaptoethanol (2-ME), alongside polyvinylpyrrolidone is commonly used in plant DNA extractions to deal with polyphenols, which could interfere with extraction and downstream applications. 2-ME is also commonly used to denature proteins and nucleases, especially RNAses. On the contrary, we found that the presence of 2-ME in lysis buffer interfered with DNA extraction from 12 strains of freshwater microalgae, resulting in DNA with poor integrity. We also found that the TNES-urea buffer, commonly used for preservation and DNA extraction from fish, appears as effective as the SDS and CTAB buffer for some microalgae strains. Results from our study suggests that the inclusion of 2-ME in DNA extraction protocols may be detrimental for isolation of good quality DNA from freshwater microalgae, and therefore recommend eliminating it or testing varying concentrations of 2-ME when developing species-specific extraction protocols for microalgae.
    Matched MeSH terms: DNA, Plant
  6. Wahyuni DK, Indriati DT, Ilham M, Murtadlo AAA, Purnobasuki H, Junairiah, et al.
    Braz J Biol, 2024;84:e278393.
    PMID: 38422290 DOI: 10.1590/1519-6984.278393
    Artemisia vulgaris L. belongs to Asteraceae, is a herbal plant that has various benefits in the medical field, so that its use in the medical field can be explored optimally, the plant must be thoroughly identified. This study aims to identify A. vulgaris both in terms of descriptive morpho-anatomy and DNA barcoding using BLAST and phylogenetic tree reconstruction. The morpho-anatomical character was observed on root, stem, and leaf. DNA barcoding analysis was carried out through amplification and alignment of the rbcL and matK genes. All studies were conducted on three samples from Taman Husada (Medicinal Plant Garden) Graha Famili Surabaya, Indonesia. The anatomical slide was prepared by the paraffin method. Morphological studies revealed that the leaves of A. vulgaris both on the lower-middle part and on the upper part of the stem have differences, especially in the character of the stipules, petioles, and incisions they have. Meanwhile, from the study of anatomy, A. vulgaris has an anomocytic type of stomata and its distribution is mostly on the ventral part of the leaves. Through the BLAST process and phylogenetic tree reconstruction, the plant sequences being studied are closely related to several species of the genus Artemisia as indicated by a percentage identity above 98% and branch proximity between taxa in the reconstructed phylogenetic tree.
    Matched MeSH terms: DNA, Plant/genetics
  7. Wagner B, Krebitz M, Buck D, Niggemann B, Yeang HY, Han KH, et al.
    J Allergy Clin Immunol, 1999 Nov;104(5):1084-92.
    PMID: 10550757
    BACKGROUND: Two natural rubber latex proteins, Hev b 1 and Hev b 3, have been described in spina bifida (SB)-associated latex allergy.

    OBJECTIVE: The aim of this study was to clone and express Hev b 3 and to obtain the immunologic active and soluble recombinant allergen for diagnosis of SB-associated latex allergy.

    METHODS: A complementary DNA (cDNA) coding for Hev b 3 was amplified from RNA of fresh latex collected from Malaysian rubber trees (Hevea brasiliensis). PCR primers were designed according to sequences of internal peptide fragments of natural (n) Hev b 3. The 5'-end sequence was obtained by specific amplification of cDNA ends. The recombinant (r) Hev b 3 was produced in Escherichia coli as a 6xHis tagged protein. Immunoblotting and inhibition assays were performed to characterize the recombinant allergen.

    RESULTS: An Hev b 3 cDNA clone of 922 bp encoding a protein of 204 amino acid residues corresponding to a molecular weight of 22.3 kd was obtained. In immunoblots 29/35, latex-allergic patients with SB revealed IgE binding to rHev b 3, as did 4 of 15 of the latex-sensitized group. The presence of all IgE epitopes on rHev b 3 was shown by its ability to abolish all IgE binding to nHev b 3. Hev b 3 is related to Hev b 1 by a sequence identity of 47%. Cross-reactivity between these 2 latex allergens was illustrated by the large extent of inhibition of IgE binding to nHev b 1 by rHev b 3.

    CONCLUSION: rHev b 3 constitutes a suitable in vitro reagent for the diagnosis of latex allergy in patients with SB. The determination of the full sequence of Hev b 3 and the production of the recombinant allergen will allow the epitope mapping and improve diagnostic reagents for latex allergy.

    Matched MeSH terms: DNA, Plant
  8. Tnah LH, Lee CT, Lee SL, Ng KK, Ng CH, Nurul-Farhanah Z, et al.
    Am J Bot, 2012 Nov;99(11):e431-3.
    PMID: 23108468 DOI: 10.3732/ajb.1200165
    Aggressive collections and trade activities in recent decades have resulted in heavy pressure on the natural stands of Aquilaria malaccensis and concerns over its long-term survival potential. To aid DNA profiling and assessment of its genetic diversity, microsatellite markers were developed for the species.
    Matched MeSH terms: DNA, Plant/genetics; DNA, Plant/chemistry
  9. Tnah LH, Lee CT, Lee SL, Ng KK, Ng CH, Hwang SS
    Am J Bot, 2011 May;98(5):e130-2.
    PMID: 21613180 DOI: 10.3732/ajb.1000469
    Microsatellite markers of an important medicinal plant, Eurycoma longifolia (Simaroubaceae), were developed for DNA profiling and genetic diversity studies.
    Matched MeSH terms: DNA, Plant/genetics*
  10. Ting NC, Zaki NM, Rosli R, Low ET, Ithnin M, Cheah SC, et al.
    J Genet, 2010 Aug;89(2):135-45.
    PMID: 20861564
    This study reports on the detection of additional expressed sequence tags (EST) derived simple sequence repeat (SSR) markers for the oil palm. A large collection of 19243 Elaeis guineensis ESTs were assembled to give 10258 unique sequences, of which 629 ESTs were found to contain 722 SSRs with a variety of motifs. Dinucleotide repeats formed the largest group (45.6%) consisting of 66.9% AG/CT, 21.9% AT/AT, 10.9% AC/GT and 0.3% CG/CG motifs. This was followed by trinucleotide repeats, which is the second most abundant repeat types (34.5%) consisting of AAG/CTT (23.3%), AGG/CCT (13.7%), CCG/CGG (11.2%), AAT/ATT (10.8%), AGC/GCT (10.0%), ACT/AGT (8.8%), ACG/CGT (7.6%), ACC/GGT (7.2%), AAC/GTT (3.6%) and AGT/ACT (3.6%) motifs. Primer pairs were designed for 405 unique EST-SSRs and 15 of these were used to genotype 105 E. guineensis and 30 E. oleifera accessions. Fourteen SSRs were polymorphic in at least one germplasm revealing a total of 101 alleles. The high percentage (78.0%) of alleles found to be specific for either E. guineensis or E. oleifera has increased the power for discriminating the two species. The estimates of genetic differentiation detected by EST-SSRs were compared to those reported previously. The transferability across palm taxa to two Cocos nucifera and six exotic palms is also presented. The polymerase chain reaction (PCR) products of three primer-pairs detected in E. guineensis, E. oleifera, C. nucifera and Jessinia bataua were cloned and sequenced. Sequence alignments showed mutations within the SSR site and the flanking regions. Phenetic analysis based on the sequence data revealed that C. nucifera is closer to oil palm compared to J. bataua; consistent with the taxanomic classification.
    Matched MeSH terms: DNA, Plant/genetics*
  11. Terauchi R
    Jpn. J. Genet., 1994 Oct;69(5):567-76.
    PMID: 7999373
    Di-nucleotide microsatellites were isolated from a genomic library of a tropical tree species, Dryobalanops lanceolata, in Sarawak, for the purpose of using them as hypervariable genetic markers to study the pollen-mediated gene flow. Among 1600 recombinant clones, in total 20 clones gave positive signals when hybridized with oligonucleotides with the three different repeat motifs, GT, CA and CT. Estimations of abundance of (GT)n/(CA)n and (GA)n/(CT)n dinucleotide repeats in D. lanceolata genome revealed to be one in every 84 kb and 80 kb, respectively. Among six sequenced microsatellite loci, one was selected to synthesize PCR primers to amplify the microsatellite. PCR product size of the locus was variable among different individuals, which is attributed to the different number of di-nucleotide repeats. The same microsatellite genotype was detected in the trunk and canopy of a single large tree, indicating the utility of trunk tissue as the source of DNA for the population genetic study of tropical tree species, the canopy of which is usually difficult to approach.
    Matched MeSH terms: DNA, Plant/genetics; DNA, Plant/isolation & purification
  12. Teo CH, Tan SH, Othman YR, Schwarzacher T
    J. Biochem. Mol. Biol. Biophys., 2002 Jun;6(3):193-201.
    PMID: 12186754
    Ty1-copia-like retrotransposons have been identified and investigated in several plant species. Here, the internal region of the reverse transcriptase (RT) gene of Ty1-copia-like retrotransposons was amplified by PCR from total genomic DNA of 10 varieties of banana. Two to four clones from each variety were sequenced. Extreme heterogeneity in the sequences of Ty1-copia-like retrotransposons from all the varieties was revealed following sequence analysis of the reverse transcriptase (RT) fragments. The size of the individual RT gene fragments varied between 213 and 309 bp. Southern blots of genomic DNA digested from Musa acuminata and other banana varieties probed with W8 clone from M. acuminata and A4 clone from Pisang Abu Nipah showed similar strong, multiple restriction fragments together with other faint hybridization band patterns with variable intensities indicating the presence of many copies of the Ty1-copia-like retrotransposons in the genomes. There was no correlation between retroelement sequence and the banana species (with A or B genomes) from which it arose, suggesting that the probes are not useful for tracking genomes through breeding populations.
    Matched MeSH terms: DNA, Plant
  13. Tan J, Lim PE, Phang SM, Hong DD, Sunarpi H, Hurtado AQ
    PLoS One, 2012;7(12):e52905.
    PMID: 23285223 DOI: 10.1371/journal.pone.0052905
    DNA barcoding has been a major advancement in the field of taxonomy, seeing much effort put into the barcoding of wide taxa of organisms, macro and microalgae included. The mitochondrial-encoded cox1 and plastid-encoded rbcL has been proposed as potential DNA barcodes for rhodophytes, but are yet to be tested on the commercially important carrageenophytes Kappaphycus and Eucheuma. This study gauges the effectiveness of four markers, namely the mitochondrial cox1, cox2, cox2-3 spacer and the plastid rbcL in DNA barcoding on selected Kappaphycus and Eucheuma from Southeast Asia. Marker assessments were performed using established distance and tree-based identification criteria from earlier studies. Barcoding patterns on a larger scale were simulated by empirically testing on the commonly used cox2-3 spacer. The phylogeny of these rhodophytes was also briefly described. In this study, the cox2 marker which satisfies the prerequisites of DNA barcodes was found to exhibit moderately high interspecific divergences with no intraspecific variations, thus a promising marker for the DNA barcoding of Kappaphycus and Eucheuma. However, the already extensively used cox2-3 spacer was deemed to be in overall more appropriate as a DNA barcode for these two genera. On a wider scale, cox1 and rbcL were still better DNA barcodes across the rhodophyte taxa when practicality and cost-efficiency were taken into account. The phylogeny of Kappaphycus and Eucheuma were generally similar to those earlier reported. Still, the application of DNA barcoding has demonstrated our relatively poor taxonomic comprehension of these seaweeds, thus suggesting more in-depth efforts in taxonomic restructuring as well as establishment.
    Matched MeSH terms: DNA, Plant/analysis; DNA, Plant/genetics
  14. Takeuchi Y, Ichikawa S, Konuma A, Tomaru N, Niiyama K, Lee SL, et al.
    Heredity (Edinb), 2004 Apr;92(4):323-8.
    PMID: 14735142
    We investigated the fine-scale genetic structure of three tropical-rainforest trees, Hopea dryobalanoides, Shorea parvifolia and S. acuminata (Dipterocarpaceae), in Peninsular Malaysia, all of which cooccurred within a 6-ha plot in Pasoh Forest Reserve. A significant genetic structure was found in H. dryobalanoides, weaker (but still significant) genetic structure in S. parvifolia and nonsignificant structure in S. acuminata. Seeds of all three species are wind dispersed, and their flowers are thought to be insect pollinated. The most obvious difference among these species is their height: S. parvifolia and S. acuminata are canopy species, whereas H. dryobalanoides is a subcanopy species. Clear differences were also found among these species in their range of seed dispersal, which depends on the height of the release point; so taller trees disperse their seed more extensively. The estimates of seed dispersal area were consistent with the degree of genetic structure found in the three species. Therefore, tree height probably had a strong influence on the fine-scale genetic structure of the three species.
    Matched MeSH terms: DNA, Plant/chemistry*
  15. Taheri S, Abdullah TL, Ahmad Z, Abdullah NA
    Biomed Res Int, 2014;2014:631813.
    PMID: 24719878 DOI: 10.1155/2014/631813
    The effects of eight different doses (0, 10, 20, 25, 35, 40, 60, and 100 Gy) of acute gamma irradiation on 44 (three varieties of Curcuma alismatifolia: Chiang Mai Red, Sweet Pink, Kimono Pink, and one Curcuma hybrid (Doi Tung 554) individual plants were investigated. Radiation sensitivity tests revealed that the LD50 values of the varieties were achieved at 21 Gy for Chiang Mai Red, 23 Gy for Sweet Pink, 25 Gy for Kimono Pink, and 28 Gy for Doi Tung 554. From the analysis of variance (ANOVA), significant variations were observed for vegetative traits, flowering development, and rhizome characteristics among the four varieties of Curcuma alismatifolia and dose levels as well as the dose × variety interaction. In irradiated plants, the leaf length, leaf width, inflorescence length, the number of true flowers, the number of pink bracts, number of shoots, plant height, rhizome size, number of storage roots, and number of new rhizomes decreased significantly (P < 0.05) as the radiation dose increased. The cophenetic correlation coefficient (CCC) between genetic dissimilarity matrix estimated from the morphological characters and the UPGMA clustering method was r = 0.93, showing a proof fit. In terms of genetic variation among the acutely irradiated samples, the number of presumed alleles revealed by simple sequence repeats ranged from two to seven alleles with a mean value of 3.1, 4.5, and 5.3 alleles per locus for radiation doses of 0, 10, and 20 Gy, respectively. The average values of the effective number of alleles, Nei's gene diversity, and Shannon's information index were 2.5-3.2, 0.51-0.66, and 0.9-1.3, respectively. The constructed dendrogram grouped the entities into seven clusters. Principal component analysis (PCA) supported the clustering results. Consequently, it was concluded that irradiation with optimum doses of gamma rays efficiently induces mutations in Curcuma alismatifolia varieties.
    Matched MeSH terms: DNA, Plant/genetics*
  16. Taheri S, Abdullah TL, Rafii MY, Harikrishna JA, Werbrouck SPO, Teo CH, et al.
    Sci Rep, 2019 Feb 28;9(1):3047.
    PMID: 30816255 DOI: 10.1038/s41598-019-39944-2
    Curcuma alismatifolia widely used as an ornamental plant in Thailand and Cambodia. This species of herbaceous perennial from the Zingiberaceae family, includes cultivars with a wide range of colours and long postharvest life, and is used as an ornamental cut flower, as a potted plant, and in exterior landscapes. For further genetic improvement, however, little genomic information and no specific molecular markers are available. The present study used Illumina sequencing and de novo transcriptome assembly of two C. alismatifolia cvs, 'Chiang Mai Pink' and 'UB Snow 701', to develop simple sequence repeat markers for genetic diversity studies. After de novo assembly, 62,105 unigenes were generated and 48,813 (78.60%) showed significant similarities versus six functional protein databases. In addition, 9,351 expressed sequence tag-simple sequence repeats (EST-SSRs) were identified with a distribution frequency of 12.5% total unigenes. Out of 8,955 designed EST-SSR primers, 150 primers were selected for the development of potential molecular markers. Among these markers, 17 EST-SSR markers presented a moderate level of genetic diversity among three C. alismatifolia cultivars, one hybrid, three Curcuma, and two Zingiber species. Three different genetic groups within these species were revealed using EST-SSR markers, indicating that the markers developed in this study can be effectively applied to the population genetic analysis of Curcuma and Zingiber species. This report describes the first analysis of transcriptome data of an important ornamental ginger cultivars, also provides a valuable resource for gene discovery and marker development in the genus Curcuma.
    Matched MeSH terms: DNA, Plant/genetics
  17. Sudheer Pamidimarri DV, Reddy MP
    Mol Biol Rep, 2014 May;41(5):3225-34.
    PMID: 24469734 DOI: 10.1007/s11033-014-3185-7
    Jatropha curcas L. (Euphorbiaceae) has acquired a great importance as a renewable source of energy with a number of environmental benefits. Very few attempts were made to understand the extent of genetic diversity and its distribution. This study was aimed to study the diversity and deduce the phylogeography of Jatropha curcas L. which is said to be the most primitive species of the genus Jatropha. Here we studied the intraspecific genetic diversity of the species distributed in different parts of the globe. The study also focused to understand the molecular diversity at reported probable center of origin (Mexico), and to reveal the dispersal route to other regions based on random amplified polymorphic DNA, amplified fragment length polymorphism and nrDNA-ITS sequences data. The overall genetic diversity of J. curcas found in the present study was narrow. The highest genetic diversity was observed in the germplasm collected from Mexico and supports the earlier hypothesis based on morphological data and natural distribution, it is the center for origin of the species. Least genetic diversity found in the Indian germplasm and clustering results revealed that the species was introduced simultaneously by two distinct germplasm and subsequently distributed in different parts of India. The present molecular data further revealed that J. curcas might have spread from the center of the origin to Cape Verde, than to Spain, Portuguese to other neighboring countries and simultaneously to Africa. The molecular evidence supports the Burkill et al. (A dictionary of the economic products of the Malay Peninsula, Governments of Malaysia and Singapore by the Ministry of Agriculture and Co-operatives. Kuala Lumpur, Malaysia, 1966) view of Portuguese might have introduced the species to India. The clustering pattern suggests that the distribution was interfered by human activity.
    Matched MeSH terms: DNA, Plant
  18. Song BK, Chuah TS, Tam SM, Olsen KM
    Mol Ecol, 2014 Oct;23(20):5003-17.
    PMID: 25231087 DOI: 10.1111/mec.12922
    Weedy rice is a close relative of domesticated rice (Oryza sativa) that competes aggressively with the crop and limits rice productivity worldwide. Most genetic studies of weedy rice have focused on populations in regions where no reproductively compatible wild Oryza species occur (North America, Europe and northern Asia). Here, we examined the population genetics of weedy rice in Malaysia, where wild rice (O. rufipogon) can be found growing in close proximity to cultivated and weedy rice. Using 375 accessions and a combined analysis of 24 neutral SSR loci and two rice domestication genes (sh4, controlling seed shattering, and Bh4, controlling hull colour), we addressed the following questions: (i) What is the relationship of Malaysian weedy rice to domesticated and wild rice, and to weedy rice strains in the USA? (ii) To what extent does the presence of O. rufipogon influence the genetic and phenotypic diversity of Malaysian weeds? (iii) What do the distributions of sh4 and Bh4 alleles and associated phenotypes reveal about the origin and contemporary evolution of Malaysian weedy rice? Our results reveal the following: independent evolutionary origins for Malaysian weeds and US strains, despite their very close phenotypic resemblance; wild-to-weed gene flow in Malaysian weed populations, including apparent adaptive introgression of seed-shattering alleles; and a prominent role for modern Malaysian cultivars in the origin and recent proliferation of Malaysian weeds. These findings suggest that the genetic complexity and adaptability of weedy crop relatives can be profoundly influenced by proximity to reproductively compatible wild and domesticated populations.
    Matched MeSH terms: DNA, Plant/genetics
  19. Song BK, Nadarajah K, Romanov MN, Ratnam W
    Cell Mol Biol Lett, 2005;10(3):425-37.
    PMID: 16217554
    The construction of BAC-contig physical maps is an important step towards a partial or ultimate genome sequence analysis. Here, we describe our initial efforts to apply an overgo approach to screen a BAC library of the Malaysian wild rice species, Oryza rufipogon. Overgo design is based on repetitive element masking and sequence uniqueness, and uses short probes (approximately 40 bp), making this method highly efficient and specific. Pairs of 24-bp oligos that contain an 8-bp overlap were developed from the publicly available genomic sequences of the cultivated rice, O. sativa, to generate 20 overgo probes for a 1-Mb region that encompasses a yield enhancement QTL yld1.1 in O. rufipogon. The advantages of a high similarity in melting temperature, hybridization kinetics and specific activities of overgos further enabled a pooling strategy for library screening by filter hybridization. Two pools of ten overgos each were hybridized to high-density filters representing the O. rufipogon genomic BAC library. These screening tests succeeded in providing 69 PCR-verified positive hits from a total of 23,040 BAC clones of the entire O. rufipogon library. A minimal tilling path of clones was generated to contribute to a fully covered BAC-contig map of the targeted 1-Mb region. The developed protocol for overgo design based on O. sativa sequences as a comparative genomic framework, and the pooled overgo hybridization screening technique are suitable means for high-resolution physical mapping and the identification of BAC candidates for sequencing.
    Matched MeSH terms: DNA, Plant*
  20. Song BK, Hein I, Druka A, Waugh R, Marshall D, Nadarajah K, et al.
    Funct Integr Genomics, 2009 Feb;9(1):97-108.
    PMID: 18633654 DOI: 10.1007/s10142-008-0091-x
    Common wild rice (Oryza rufipogon) plays an important role by contributing to modern rice breeding. In this paper, we report the sequence and analysis of a 172-kb genomic DNA region of wild rice around the RM5 locus, which is associated with the yield QTL yld1.1. Comparative sequence analysis between orthologous RM5 regions from Oryza sativa ssp. japonica, O. sativa ssp. indica and O. rufipogon revealed a high level of conserved synteny in the content, homology, structure, orientation, and physical distance of all 14 predicted genes. Twelve of the putative genes were supported by matches to proteins with known function, whereas two were predicted by homology to rice and other plant expressed sequence tags or complementary DNAs. The remarkably high level of conservation found in coding, intronic and intergenic regions may indicate high evolutionary selection on the RM5 region. Although our analysis has not defined which gene(s) determine the yld1.1 phenotype, allelic variation and the insertion of transposable elements, among other nucleotide changes, represent potential variation responsible for the yield QTL. However, as suggested previously, two putative receptor-like protein kinase genes remain the key suspects for yld1.1.
    Matched MeSH terms: DNA, Plant/genetics*
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