Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Harpke, Doerte  (14)
Type of Medium
Language
Year
  • 1
    Language: English
    In: International Journal of Plant Sciences October 2007, Vol.168(8), pp.1157-1160
    Description: The increasing number of pseudogenic internal transcribed spacer (ITS) regions (ITS1, 5.8S rDNA, ITS2) reported for plant taxa raises questions—for example, concerning the proportion of functional copies. Our application of quantitative PCR (qPCR) with genomic DNA under stringent conditions revealed that 〈3% of the copies of the ITS region were putatively functional in the genomic PCR pool in Mammillaria . The selective amplification of functional copies of the ITS region was possible through the utilization of conserved angiosperm motifs (ITS1 motif and 5.8S motif) as primer annealing sites. Our study displays that it is possible to quantify the proportion of functional copies of repetitive DNA regions through their selective amplification by qPCR.
    Keywords: Polymerase Chain Reaction -- Genetic Aspects ; Genomic Libraries -- Evaluation ; Angiosperms -- Genetic Aspects ; Genetic Polymorphisms -- Evaluation;
    ISSN: 10585893
    E-ISSN: 15375315
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    In: PLoS ONE, 2016, Vol.11(4)
    Description: Most flowers display distinct colour patterns comprising two different areas. The peripheral large-area component of floral colour patterns attracts flower visitors from some distance and the central small-area component guides flower visitors towards landing sites. Whereas the peripheral colour is largely variable among species, the central colour, produced mostly by anthers and pollen or pollen mimicking floral guides, is predominantly yellow and UV-absorbing. This holds also for yellow flowers that regularly display a UV bull’s eye pattern. Here we show that yellow-flowering Crocus species are a noticeable exception, since yellow-flowering Crocus species–being entirely UV-absorbing–exhibit low colour contrast between yellow reproductive organs and yellow tepals. The elongated yellow or orange-yellow style of Crocus flowers is a stamen-mimicking structure promoting cross-pollination by facilitating flower visitors’ contact with the apical stigma before the flower visitors are touching the anthers. Since Crocus species possess either yellow, violet or white tepals, the colour contrast between the stamen-mimicking style and the tepals varies among species. In this study comprising 106 Crocus species, it was tested whether the style length of Crocus flowers is dependent on the corolla colour. The results show that members of the genus Crocus with yellow tepals have evolved independently up to twelve times in the genus Crocus and that yellow-flowering Crocus species possess shorter styles as compared to violet- and white-flowering ones. The manipulation of flower visitors by anther-mimicking elongated styles in Crocu s flowers is discussed.
    Keywords: Research Article ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Biology And Life Sciences ; Research And Analysis Methods ; Biology And Life Sciences
    E-ISSN: 1932-6203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Language: English
    In: Molecular Phylogenetics and Evolution, 2006, Vol.41(3), pp.579-593
    Description: Molecular studies of 21 species of the large Cactaceae genus representing a variety of intrageneric taxonomic levels revealed a high degree of intra-individual polymorphism of the internal transcribed spacer region (ITS1, 5.8S rDNA, ITS2). Only a few of these ITS copies belong to apparently functional genes, whereas most are probably non-functional (pseudogenes). As a multiple gene family, the ITS region is subjected to concerted evolution. However, the high degree of intra-individual polymorphism of up to 36% in ITS1 and up to 35% in ITS2 suggests a non-concerted evolution of these loci in . Conserved angiosperm motifs of ITS1 and ITS2 were compared between genomic and cDNA ITS clones of . Some of these motifs (e.g., ITS1 motif 1, ‘TGGT’ within ITS2) in combination with the determination of GC-content, length comparisons of the spacers and ITS2 secondary structure (helices II and III) are helpful in the identification of pseudogene rDNA regions.
    Keywords: Internal Transcribed Spacer ; Non-Concerted Evolution ; Mammillaria ; Pseudogene ; Its Motifs ; Its2 Secondary Structure ; Biology
    ISSN: 1055-7903
    E-ISSN: 1095-9513
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: Organisms Diversity & Evolution, 2011, Vol.11(5), pp.387-407
    Description: A new region of speciation for the genus Gagea (Liliaceae) was investigated (Bogda-Shan and Urumqi; northwestern Xinjiang, China). Two species were recorded as new for the region ( G. rufidula , G. davlianidzeae ); three species are described as new to science ( G. angelae, G. jensii and G. huochengensis ). The description of G. nigra is emendated. Sequence data (cpDNA: trn L- trn F IGS+ psb A- trn H IGS, nrDNA: ITS), including representatives of all Gagea sections, were used to compare the new species with closely related taxa. A nuclear single copy gene region (pCOS At 103) was analysed for representatives of the Sects. Minimae and Gagea . Network analysis of cpDNA and nDNA indicates hybridization and recent speciation in Xinjiang. ITS and pCOS At 103 sequences reveal gene flow between G. davlianidzeae and G. nigra . A cpDNA haplotype network constructed from representatives of Sect. Gagea was highly informative phylogenetically. Gagea angelae and G . huochengensis , sharing gene flow, are related closely to a basal clade represented by G. ancestralis , G. xiphoidea and G. capusii , which may include the putative progenitor of all other taxa of the large Eurasian Sect. Gagea . Whereas speciation in Sect. Minimae seems to be driven mainly by hybridization, speciation in the Sect. Gagea may be influenced by both hybridization and geographical separation. We confirm the monophyly of Sects. Bulbiferae and Minimae .
    Keywords: cpDNA ; Gagea ; hybridization ; ITS ; Liliales ; At ; speciation
    ISSN: 1439-6092
    E-ISSN: 1618-1077
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Language: English
    In: Italian Botanist, 01 September 2018, Vol.6, pp.23-30
    Description: The Italian endemic Crocus biflorus usually shows white or lilac flowers with three-to-five striking violet longitudinal stripes on the outer tepals, but unstriped plants were recorded in the past. These plants were originally described as C. annulatus subvar. estriatus, and subsequently recombined as a variety of C. biflorus. The rediscovery of such plants in Toscana gave us the opportunity to clarify their systematic relationships, so that we typified the name, and performed karyological and ITS analyses. These plants share the same chromosome number (2n = 2x = 8) and ITS sequence with C. biflorus s. str.
    Keywords: Botany
    E-ISSN: 2531-4033
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    In: Phytotaxa, 12/24/2015, Vol.239(3), p.223
    ISSN: 1179-3155
    E-ISSN: 1179-3163
    Source: CrossRef
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    In: Phytotaxa, 03/10/2017, Vol.298(2), p.173
    ISSN: 1179-3155
    E-ISSN: 1179-3163
    Source: CrossRef
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Language: English
    In: Canadian Journal of Botany, March, 2008, Vol.86(3), p.300(6)
    Keywords: Phylogeny -- Research ; Pseudogenes -- Identification And Classification ; Plant Genetics -- Research
    ISSN: 0008-4026
    Source: Cengage Learning, Inc.
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Language: English
    In: Journal of Plant Research, 2008, Vol.121(3), pp.261-270
    Description: The internal transcribed spacer (ITS) region (ITS1, 5.8S rDNA, ITS2) represents the most widely applied nuclear marker in eukaryotic phylogenetics. Although this region has been assumed to evolve in concert, the number of investigations revealing high degrees of intra-individual polymorphism connected with the presence of pseudogenes has risen. The 5.8S rDNA is the most important diagnostic marker for functionality of the ITS region. In Mammillaria , intra-individual 5.8S rDNA polymorphisms of up to 36% and up to nine different types have been found. Twenty-eight of 30 cloned genomic Mammillaria sequences were identified as putative pseudogenes. For the identification of pseudogenic ITS regions, in addition to formal tests based on substitution rates, we attempted to focus on functional features of the 5.8S rDNA (5.8S motif, secondary structure). The importance of functional data for the identification of pseudogenes is outlined and discussed. The identification of pseudogenes is essential, because they may cause erroneous phylogenies and taxonomic problems.
    Keywords: 5.8S rDNA ; Intra-individual variability ; Mammillaria ; Pseudogene ; Secondary structure
    ISSN: 0918-9440
    E-ISSN: 1618-0860
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Language: English
    In: Plant Systematics and Evolution, 2016, Vol.302(8), pp.985-1007
    Description: The most important center of speciation in the genus Gagea is thought to be in Central Asia. Here, we focus on species diversity in southeastern Kazakhstan (around Almaty, Ili-Alatau range of the Western Tian-Shan mountains). We studied an elevational transect, reaching from lowland steppes to the alpine zone (500–2750 m a. s. l.), and carried out detailed morphological and molecular investigations for populations of Gagea spp. Nine species were identified in different altitudinal zones; one of these ( Gagea almaatensis ) is described as new to science. We could detect two altitudinal contact zones between closely related species: G . filiformis and G. granulosa (sect. Minima e), and G . almaatensis and G. kuraminica (sect. Gagea ). Morphological and molecular investigations (ITS data and cpDNA networks) indicate ongoing hybridization of co-occurring G. filiformis into G. granulosa and putative bidirectional hybridization events between G. almaatensis and G. kuraminica.
    Keywords: cpDNA ; Gagea ; Hybridization ; ITS ; Phylogeny ; Taxonomy
    ISSN: 0378-2697
    E-ISSN: 2199-6881
    E-ISSN: 16156110
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages