Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    ISSN: 1573-5028
    Keywords: Cab genes ; chlorophylla/b-binding protein ; Pisum sativum ; nucleotide sequence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-5028
    Keywords: chromatin structure ; gene silencing ; MAR ; nuclear matrix ; nuclear scaffold ; SAR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Matrix attachment regions (MARs) are operationally defined as DNA elements that bind specifically to the nuclear matrix in vitro. It is possible, although unproven, that they also mediate binding of chromatin to the nuclear matrix in vivo and alter the topology of the genome in interphase nuclei. When MARs are positioned on either side of a transgene their presence usually results in higher and more stable expression in transgenic plants or cell lines, most likely by minimizing gene silencing. Our review explores current data and presents several plausible models to explain MAR effects on transgene expression.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-5028
    Keywords: DNA sequence ; ferredoxin ; genomic organisation ; pea ; phytochrome ; Fd: ferrdoxin protein ; Fed: ferredoxin gene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have sequenced the pea (cv. Alaska) cDNA clone pEA46 (16) and shown that it codes for ferredoxin I. This clone has previously been shown to correspond to a transcript whose levels are controlled by phytochrome (Kaufman et al. (1985) Plant Physiol. 78: 388–393; Thompson et al. (1983) Planta 158: 487–500). The deduced amino acid sequence includes part of an hydrophobic transit sequence that shows only very limited homology to that of Silene pratensis ferredoxin. Genomic blotting analysis indicates that ferredoxin I is encoded by one or two genes. A genomic clone (4601) has been isolated that contains the ferredoxin gene and at least 14 kb of flanking sequences.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-5028
    Keywords: Arabidopsis thaliana ; chimeric genes ; ferredoxin ; light regulation ; Nicotiana tabacum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effect of light on the expression of the Arabidopsis thaliana ferredoxin gene (fedA) was studied in mature tobacco plants. In light-treated leaves of tobacco plants transformed with a full-length ferredoxin gene, fedA-specific mRNA levels were more than twenty fold higher than in dark-treated controls. This indicates that all components for regulation of the Arabidopsis ferredoxin gene are present in tobacco. To identify light-regulatory elements in the fedA gene, we have tested a set of chimeric genes containing various parts of the fedA gene for light-dependent expression in mature tobacco plants. A fedA promoter-GUS fusion gene was not light-responsive, indicating that the 5′-upstream promoter region is not sufficient for light regulation. Fusion genes in which different transcribed regions of the fedA gene were expressed from the CaMV 35S promoter showed only limited light regulation, if any at all. This indicates that, like the fedA upstream region, the region downstream of the transcription start site is also not sufficient for full light regulation. The combined results suggest that for full light-regulated expression of the fedA gene, both the promoter region and sequences downstream of the transcription start site are required.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1573-5028
    Keywords: Repeated DNA ; genes ; interspersion ; sequence divergence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The pattern of sequence organization in the regions of the pea genome near sequences coding for mRNA differs significantly from that in total DNA. Interspersion of repeated and single copy sequences is so extensive that 85% of 1300 nucleotide-long fragments contain highly repetitive sequences (about 5000 copies per haploid genome). However, data presented here demonstrate that sequences which code for mRNA are enriched in the small fraction of fragments which do not contain these highly repetitive sequences. Thus, in contrast to the great majority of other sequences in the genome, most mRNA coding sequences are not located within 1300 nucleotides of highly repetitive elements. Moreover, our data indicate that those repeats (if any) which are closely associated with mRNA coding sequences belong to low copy number families characterized by an unusually low degree of sequence divergence.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-5028
    Keywords: AT-rich sequences ; DNA-binding proteins ; ferredoxin I ; HMG ; high mobility group proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract AT-rich sequences in the 5′ flanking regions of several plant genes have been shown to bind nuclear proteins, but the nature of these proteins has remained largely unknown. We report here that certain plant high mobility group (HMG) chromosomal proteins can interact specifically (in the presence of excess non-specific competitor) with AT-rich sequences located upstream of the pea ferredoxin 1 gene (Fed-1) and a member of the wheat Em gene family. Binding was observed with highly purified preparations of HMGa or HMGb, but not with HMGc or HMGd. HMG-DNA complexes were similar to one of the two types of Fed-1 complexes we observed previously using pea nuclear extracts [7]. HMG binding to the Fed-1 DNA was localized to a region containing AT-rich sequences; very similar sequences are present 5′ to Em and several other plants genes. Such sequences have been shown to bind unidentified nuclear proteins in a number of these systems. Binding experiments with a synthetic oligo (dA) • oligo (dT) probe and competition experiments with synthetic DNA polymers suggest that HMG binding may depend upon structural features of AT-rich DNA rather than being sequence-specific. We discuss the implications of these findings and suggest a role for HMG binding which is consistent with previous evidence linking HMGs with transcriptionally competent chromatin.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1573-5028
    Keywords: Cab genes ; chlorophylla/b-binding protein ; Pisum sativum ; nucleotide sequence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1573-5028
    Keywords: Ac ; Ds ; β-glucuronidase ; methotrexate resistance ; tobacco ; transposon tagging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This report describes a series of transposon tagging vectors for dicotyledonous plants based on the maize transposable element Ac. This binary system includes the transposase (Ts) and the tagging element (Ds) on separate T-DNA vectors. Ts elements include versions in which transcription is driven either by the endogenous Ac promoter or by the cauliflower mosaic virus (CaMV) 35S promoter. Ds tagging element includes a gene conferring methotrexate (Mtx) resistance for selection and a supF gene to facilitate cloning of tagged sequences. The Ds element is flanked by a CaMV 35S promoter and the β-glucuronidase (GUS) coding sequence so that GUS expression occurs upon excision of the element. We have transformed these Ts and Ds elements into tobacco and demonstrated that the Ts is functional with either promoter, and that the artificial Ds elements are capable of transposition. The amount of excision was found to depend upon both the individual Ts and Ds primary transformants used. Somatic excision of Ds was seen in up to 100% of progeny seedlings containing Ts and Ds. Germinal excision was detected in up to 48% of the progeny of plants containing both elements. Hence, this system can generate a sufficient number of events to be useful in gene tagging.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1432-0983
    Keywords: Intron ; Mitochondrial DNA ; Mitochondrial gene ; Unidentified reading frame
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have cloned and sequenced a fragment of watermelon mitochondrial DNA (mtDNA) which contains a gene homologous to mitochondrial URF-1 (Unidentified Reading Frame-1) of vertebrates, Drosophila yakuba and Aspergillus nidulans. URF-1 is thought to encode a component of the respiratory chain NADH dehydrogenase. Two coding regions in the watermelon gene are separated by approximately 1,450 by of untranslatable DNA. These two exons encode the central portions of URF-1, and are highly conserved. We postulate that three additional exons, selected by their map location and amino acid homology to other URF-1 sequences, encode the remainder of the polypeptide. This is the first description of a plant mitochondrial gene with multiple introns.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-0983
    Keywords: Inverted repeat ; Colinearity ; Flip-flop recombination ; Fern chloroplast DNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The evolution and recombination of chloroplast genome structure in the fern genus Osmunda were studied by comparative restriction site mapping and filter hybridization of chloroplast DNAs (cpDNAs) from three species — 0. cinnamomea, 0. claytoniana and 0. regalis. The three 144 kb circular genomes were found to be colinear in organization, indicating that no major inversions or transpositions had occurred during the approximately 70 million years since their radiation from a common ancestor. Although overall size and sequence arrangement are highly conserved in the three genomes, they differ by an extensive series of small deletions and insertions, ranging in size from 50 bp to 350 by and scattered more or less at random throughout the circular chromosomes. All three chloroplast genomes contain a large inverted repeat of approximately 10 kb in size. However, hybridizations using cloned fragments from the 0. cinnamomea and 0. regalis genomes revealed the absence of any dispersed repeats in at least 50% of the genome. Analysis with restriction enzymes that fail to cleave the 10 kb inverted repeat indicated that each of the three fern chloroplast genomes exists as an equimolar population of two isomeric circles differing only in the relative orientation of their two single copy regions. These two inversion isomers are inferred to result from high frequency intramolecular recombination between paired inverted repeat segments. In all aspects of their general organization, recombinational heterogeneity, and extent of structural rearrangement and length mutation, these fern chloroplast genomes resemble very closely the chloroplast genomes of most angiosperms.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...