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881.
Natural hybridization in Taraxacum between native sexual diploids and introduced agamospermous triploids occurring in Japan was studied by means of chloroplast
DNA (cpDNA) marker. We first determined the nucleotide sequences between trnT (UGU) and trnF (GAA) of cpDNA for 22 plants obtained from Japan and Europe. The sequences analyzed were about 1,574 base pairs long. Among
all accessions, the total numbers of polymorphic characters were 56 nucleotide substitutions, three insertions/deletions (ins/dels),
and one repeat number polymorphism of mononucleotide motif. Of these polymorphic characters, four nucleotides and one ins/del
were applicable in the discrimination between Japanese and European taxa of dandelions. We selected the ins/del in an intergenic
region between trnL (UAA) 3′ exon and trnF (GAA) as a cpDNA marker. Using a newly developed cpDNA marker, 225 plants of putative Taraxacum officinale collected from 11 populations in Niigata City were investigated. Eighty-two percent of them showed a Japanese haplotype of
cpDNA, and they were regarded as hybrids. Compared with the previous studies, it is likely that the prevalence of the hybrid
plants is a general phenomena at least in urban areas in Japan. The validity of the cpDNA marker for screening Taraxacum hybrids is discussed.
Electronic Publication 相似文献
882.
Yamaguchi T Shioji I Sugimoto A Yamaoka M 《Biochemical and biophysical research communications》2002,293(1):517-520
Some authors have suggested that psychological stress induces the production of reactive oxygen species (ROS). Some studies have supported that bilirubin exerts anti-oxidative effects in vivo. However, it is not known whether ROS induced by psychological stress provoke bilirubin oxidation in vivo. We investigated if the concentration of bilirubin oxidative metabolite (BOM), a bilirubin oxidative metabolite, increased in urine from subjects exposed to psychological stress. Sixty healthy male volunteers working in a pharmaceutical company were divided into a Group I which did not attend a conference, a Group II which attended a conference but did not deliver a speech, and a Group III which attended a conference and delivered speeches in the presence of the company executives. Subjective stress was scored (self-rating score) after subjects in Group III delivered their speeches at the conference. Urine was collected on the next day. The BOM concentrations, as measured by enzyme-linked immunosorbent assay, were normalized to the urinary concentration of creatinine. The concentration of BOM in Group III was significantly higher compared to that in Groups I and II (p<0.01 and p<0.05, respectively). Furthermore, in Group III, the concentration of BOM correlated with the self-rating stress score (r=0.53, p<0.01). These findings suggest that emotional stimuli are associated with an increase in the oxidative metabolites of bilirubin in human urine, and that BOMs could be useful markers of psychological stress. 相似文献
883.
Bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae is one of the most important diseases affecting rice production in Asia. We were interested in surveying rice genotypes that are popularly used in the Indian breeding program for conferring resistance to bacterial blight, using 11 STMS and 6 STS markers. The basis of selection of these DNA markers was their close linkage to xa5, xa13, and Xa21 genes and their positions on the rice genetic map relative to bacterial blight resistance genes. Eight lines were found to contain the xa5 gene while two lines contained Xa21 gene and none of the lines contained the xa13 gene with the exception of its near-isogenic line. Using the polymorphic markers obtained in the initial survey, marker-assisted selection was performed in the F3 population of a cross between IR-64 and IET-14444 to detect lines containing multiple resistance genes. Of the 59 progeny lines analyzed, eight lines contained both the resistance genes, xa5 and Xa4. 相似文献
884.
Multiple pathways for Cre/lox-mediated recombination in plastids 总被引:13,自引:0,他引:13
Hajdukiewicz PT Gilbertson L Staub JM 《The Plant journal : for cell and molecular biology》2001,27(2):161-170
Plastid transformation technology involves the insertion by homologous recombination and subsequent amplification of plastid transgenes to approximately 10 000 genome copies per leaf cell. Selection of transformed genomes is achieved using a selectable antibiotic resistance marker that has no subsequent role in the transformed line. We report here a feasibility study in the model plant tobacco, to test the heterologous Cre/lox recombination system for antibiotic marker gene removal from plastids. To study its efficiency, a green fluorescent protein reporter gene activation assay was utilized that allowed visual observation of marker excision after delivery of Cre to plastids. Using a combination of in vivo fluorescence activation and molecular assays, we show that transgene excision occurs completely from all plastid genomes early in plant development. Selectable marker-free transplastomic plants are obtained in the first seed generation, indicating a potential application of the Cre/lox system in plastid transformation technology. In addition to the predicted transgene excision event, two alternative pathways of Cre-mediated recombination were also observed. In one alternative pathway, the presence of Cre in plastids stimulated homologous recombination between a 117 bp transgene expression element and its cognate sequence in the plastid genome. The other alternative pathway uncovered a plastid genome 'hot spot' of recombination composed of multiple direct repeats of a 5 bp sequence motif, which recombined with lox independent of sequence homology. Both recombination pathways result in plastid genome deletions. However, the resultant plastid mutations are silent, and their study provides the first insights into tRNA accumulation and trans-splicing events in higher plant plastids. 相似文献
885.
Effects of sequential pollination on the success of "fast" and "slow" pollen donors in Hibiscus moscheutos (Malvaceae) 总被引:1,自引:0,他引:1
Competition among pollen grains for the chance to fertilize ovules typically involves two stages: arrival times on stigmas and/or the growth of pollen tubes through styles. In a previous study of Hibiscus moscheutos, we found that individual pollen donors often differed in pollen tube competitive ability. Here we determined whether short delays in pollen arrival time altered the average success of "fast" and "slow" pollen donors when both types of pollen experienced the same delays. Hand-pollination experiments were carried out using four pairs of pollen donors that differed in competitive ability. We allowed delays of 15 or 30 min between the first and second pollen donor and then determined seed paternity using allozyme markers. The second donor typically sired fewer seeds than pollen that arrived earlier, but, contrary to expectation, "faster" pollen did not always sire significantly more seeds than "slower" pollen when each was applied after delays of the same duration. In two of the four pairs of donors, differences that were seen following simultaneous pollinations disappeared when each type of pollen was applied following identical delays of 15 or 30 min. This unexpected response suggests that the dynamics of pollen tube competition are more complex than anticipated. 相似文献
886.
Stone JL 《American journal of botany》2000,87(3):348-354
In this paper, I investigate whether the presence or absence of anthocyanin is neutral with respect to reproduction in Datura stramonium. The observations concern the portion of the life cycle spanning pollination to germination. Pollinators do not appear to distinguish between floral morphs, as revealed by nonbiased distribution of fluorescent powder used as a pollen analogue. Pollen-tube growth is also equal for the two morphs. Seed germination is affected by the presence of anthocyanin, but apparently only by the genotype of the mother at the anthocyanin locus, and not by the genotype of the embryo itself. In addition, there was an interaction between maternal morph and the maternal source population, with seeds from high-elevation anthocyanin-producing mothers germinating most rapidly and seeds from low-elevation anthocyanin-producing mothers germinating most slowly in a common garden at low elevation. However, because germination of anthocyanin-producing and anthocyaninless progeny proceed equally quickly, the anthocyanin marker provides unbiased estimates of outcrossing rates. The results overall support the use of anthocyanin as a neutral marker, with the alternate phenotypes unlikely to be differentially impacted by the processes of pollination, pollen-tube growth, and germination. Fluctuating selection on conditions for dormancy release may be partially responsible for the maintenance of the anthocyanin polymorphism in Datura stramonium. 相似文献
887.
波尔山羊9个微卫星标记与产羔性状的关联研究 总被引:3,自引:0,他引:3
选择与绵羊高繁殖力主效基因FecB和FecX紧密连锁的5个微卫星标记BM1329, BM143, OarHH55, TGLA68和LSCV043, 和其他4个微卫星标记ETH225, INRA063, BM1225和MAF0214, 分析研究其与波尔山羊产羔数的关联。结果表明: 所研究的9个波尔山羊微卫星基因座均为高度多态性基因座(PIC > 0.5)。找到与波尔山羊产羔性状显著相关的等位基因计12个。其中与波尔山羊第一胎产羔数有显著正效应的等位基因3个: BM143的120 bp和108 bp, ETH225的183 bp; 与波尔山羊第一胎产羔数有显著负效应的等位基因8个: BM1329的216 bp、BM143的110 bp、BM1225的255 bp和239 bp、INRA063的175 bp、177 bp和189 bp, ETH225的163 bp。与波尔山羊第二胎产羔数有显著正效应的等位基因1个: TGLA68的115 bp。 相似文献
888.
B. von Malek W. E Weber T. Debener 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(5-6):977-983
Blackspot resistance in the tetraploid rose genotype 91/100–5 had been characterised previously as a single dominant gene
in duplex configuration. In the present study a tetraploid progeny (95/3) segregating for the presence of the blackspot resistance
gene Rdr1 were screened with 868 RAPD and 114 AFLP primers/primer combinations. Seven AFLP markers were found to be linked to Rdr1 at distances between 1.1 and 7.6 cM. The most closely linked AFLP marker was cloned and converted into a SCAR marker that
could be screened in a larger population than the original AFLP and was linked at a distance of 0.76 cM. The cloned fragment
was used as an RFLP probe to locate the marker on a chromosome map of diploid roses. This is the first report of markers linked
to a resistance gene in roses, and the possibilities of using them for a marker-assisted selection for blackspot resistance
as well as for map-based cloning approaches are discussed.
Received: 23 December 1999 / Accepted: 25 March 2000 相似文献
889.
Y. B. Fu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(8):1284-1289
Two bulking procedures (bulking individuals before and after genotyping) are commonly applied in similarity based studies
of genetic distance at the population or higher level, but their effectiveness is largely unknown. In this study, expected
population-pairwise similarity for both bulking procedures is derived with dominant and co-dominant diallelic markers. Numerical
examples for the derived formulae are given with up to ten individuals randomly selected from each population. The procedure
of bulking individuals after genotyping with either marker system is generally more informative than the procedure of bulking
individuals before genotyping, because the former incorporates the information from marker alleles of intermediate frequency.
Both procedures are effective with 5–10 individuals selected randomly from either population, but the procedure of bulking
before genotyping requires a genotyping effort several-fold less than the procedure of bulking after genotyping. For either
bulking procedure, a co-dominant marker system is generally more informative than a dominant marker system.
Received: 20 October 1999 / Accepted: 11 November 1999 相似文献
890.
Suppression subtractive hybridization was used to identify genes regulated by ozone (100 nmol mol ? 1) in Pisum sativum. One novel gene (named PsUod1) was found. In addition, mRNA levels for four genes (encoding lipid transfer protein, pre‐hevein‐like protein, leucine‐rich repeat protein, and disease‐resistance response protein 230), which previously were shown to be regulated by biotic stress, increased. Finally, mRNA species for two genes (encoding extensin and pathogenesis‐related protein 4A), previously shown to be regulated by ozone in other species, were found to increase in abundance. The ozone‐specificity of the expression of these genes was studied by using UV‐B radiation. PsUod1 and the genes encoding extensin, leucine‐rich repeat protein, and disease‐resistance response protein 230, were differentially regulated when comparing ozone and UV‐B. Moreover, the mRNA levels for extensin, leucine‐rich repeat protein and disease‐resistance response protein 230 all increased under NaCl and aluminium stress and after wounding, whereas the message abundance for PsUod1 was unchanged under these stresses. Thus, in general, ozone caused changes similar to wounding, salt stress and aluminium stress, whereas UV‐B radiation regulated gene expression differently. 相似文献