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51.
52.
W. Y. Cheung T. A. Money S. Abbo K. M. Devos M. D. Gale G. Moore 《Molecular & general genetics : MGG》1994,245(3):349-354
A family of related sequences associated with (TTTAGGG)
n
repeats has been cloned from the wheat cultivar Chinese Spring. These sequences reveal a high level of polymorphism between wheat varieties when used as restriction fragment length polymorphism (RFLP) probes. Although this family of sequences contains motifs homologous to the repeats in the telomeres of wheat, they are located at interstitial sites on wheat chromosomes. 相似文献
53.
A physical map and clone bank of the black pine (Pinus thunbergii) chloroplast genome 总被引:1,自引:1,他引:0
T. Wakasugi J. Tsudzuki S. Ito M. Shibata M. Sugiura 《Plant Molecular Biology Reporter》1994,12(3):227-241
Black pine chloroplast DNA is 119,707 bp long. The physical map is shown and the genes are listed. Plasmid clones covering
the entire DNA sequence have been ordered and available upon request. 相似文献
54.
S. Fauré J. L. Noyer J. P. Horry F. Bakry C. Lanaud D. Gońzalez de León 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,87(4):517-526
A partial molecular linkage map of the Musa acuminata diploid genome is presented. This map is based on 58 RFLP, four isozyme and 28 RAPD markers segregating in an F2 population of 92 individuals. A total of 90 loci was detected, 77 of which were placed on 15 linkage groups while 13 segregated independently. Segregation distortions were shown by 36% of all loci, mostly favoring the male parent. Chromosome structural rearrangements were believed to be one of the main causes of these distortions. The use of genetic linkage data to further the genetic and evolutionary knowledge of the genus Musa, as well as to help improve the design of breeding strategies, is discussed. 相似文献
55.
L. M. Mansur K. G. Lark H. Kross A. Oliveira 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(8):907-913
Quantitative trait loci (QTL) were mapped in segregating progeny from a cross between two soybean (Glycine max (L.) Merr.) cultivars: Minsoy (PI 27.890) and Noir 1 (PI 290.136). The 15 traits analyzed included reproductive, morphological, and seed traits, seed yield and carbon isotope discrimination ratios (13C/12C). Genetic variation was detected for all of the traits, and transgressive segregation was a common phenomenon. One hundred and thirty-two linked genetic markers and 24 additional unlinked markers were used to locate QTL by interval mapping and one-way analysis of variance, respectively. Quantitative trait loci controlling 11 of the 15 traits studied were localized to intervals in 6 linkage groups. Quantitative trait loci for developmental and morphological traits (R1, R5, R8, plant height, canopy height, leaf area, etc.) tended to be clustered in three intervals, two of which were also associated with seed yield. Quantitative trait loci for seed oil were separated from all the other QTL. Major QTL for maturity and plant height were linked to RFLP markers R79 (31% variation) and G173 (53% variation). Quantitative trait loci associated with unlinked markers included possible loci for seed protein and weight. Linkage between QTL is discussed in relation to the heritability and genetic correlation of the traits. 相似文献
56.
伪狂犬病毒闽A株基因文库的构建及物理图谱分析 总被引:6,自引:0,他引:6
本文报道以质粒pBR322作载体,用鸟枪法克隆出了PRV闽A株除BamHI-1,2外的所有酶切片段,构建了PRV闽A株基因文库,并以克隆出的BamHI片段用光生物素标记作探针,应用分子杂交法确定了PRV闽A株绝大部分限制性内切酶位点的位置。 相似文献
57.
灰茶尺蛾核型多角体病毒某些生化特性的研究 总被引:1,自引:0,他引:1
灰茶尺蛾核型多角体病毒某些生化特性的研究李彦章,石正丽,陈棣华(中国科学院武汉病毒研究所,武汉430071)关键词灰茶尺蛾,核型多角体病毒,结构多肽,限制性内切酶图谱灰茶尺蛾核型多角体病毒(Ectropisgrisescensnuclearpolyh... 相似文献
58.
Wilfried Bautsch 《Molecular biotechnology》1994,2(1):29-44
Macrorestriction mapping is often the first step toward a thorough physical and genetic characterization of a bacterial genome.
The problem of deducing the order of partially or completely digested macrorestriction fragments to yield a physical genome
map may readily be solved by applying twodimensional pulsed-field gel electrophoresis (2D-PFGE) techniques. These powerful
methods are quick and technically easy to perform; specifically, they are independent of DNA probes and should therefore be
applicable to any bacterial species irrespective of its prior genetic characterization. In this article, detailed step-by-step
protocols are given to set up, run, and evaluate 2D pulsed-field gels. Two basic methods are described: partial/complete 2D
gels of one restriction enzyme and complete/complete 2D gels of two different restriction enzymes. Other topics include preparation
of bacterial genomic DNA, screening for suitable rare-cutting restriction enzymes and determination of optimal running conditions.
Accompanied by many notes, these protocols are meant to offer the novice a sound and rapid access to these important methods. 相似文献
59.
The nuclear 18S, 5.8S and 25S rRNA genes exist as thousands of rDNA repeats in the Scots pine genome. The number and location
of rDNA loci (nucleolus organizers, NORs) were studied by cytological methods, and a restriction map from the coding region
of the Scots pine rDNA repeat was constructed using digoxigenin-labeled flax rDNA as a probe. Based on the maximum number
of nucleoli and chromosomal secondary constrictions, Scots pine has at least eight NORs in its haploid genome. The size of
the Scots pine rDNA repeat unit is approximately 27 kb, two- or threefold larger than the typical angiosperm rDNA unit, but
similar in size to other characterized conifer rDNA repeats. The intergenic spacer region (IGS) of the rDNA repeat unit in
Scots pine is longer than 20 kb, and the transcribed spacer regions surrounding the 5.8S gene (ITS1 and ITS2) span a region
of 2.9 kb. Restriction analysis revealed that although the coding regions of rDNA repeats are homogeneous, heterogeneity exists
in the intergenic spacer region between individuals, as well as among the rDNA repeats within individuals. 相似文献
60.
K. G. Lark J. M. Weisemann B. F. Matthews R. Palmer K. Chase T. Macalma 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(8):901-906
Genetic markers were mapped in segregating progeny from a cross between two soybean (Glycine max (L.) Merr.) cultivars: Minsoy (PI 27.890) and Noir 1 (PI 290.136). A genetic linkage map was constructed (LOD 3), consisting of 132 RFLP, isozyme, morphological, and biochemical markers. The map defined 1550cM of the soybean genome comprising 31 linkage groups. An additional 24 polymorphic markers remained unlinked. A family of RFLP markers, identified by a single probe (hybridizing to an interspersed repeated DNA sequence), extended the map, linking other markers and defining regions for which other markers were not available. 相似文献