Search Results - (Author, Cooperation:R. Appels)

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  1. 1
    Staff View
    Publication Date:
    2013-03-29
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Adaptation, Physiological/*genetics ; Brachypodium/genetics ; Chromosome Mapping ; Chromosomes, Plant/genetics ; DNA Transposable Elements/genetics ; Disease Resistance/genetics ; Genes, Plant/genetics ; Genome, Plant/*genetics ; Hordeum/genetics ; Molecular Sequence Data ; Plant Diseases ; Poaceae/*genetics ; Polyploidy ; Sequence Analysis, RNA ; Transcription Factors/genetics ; Triticum/*genetics/physiology
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  2. 2
    The International Wheat Genome Sequencing Consortium (IWGSC), IWGSC Ref; Seq principal investigators:, Appels, R., Eversole, K., Feuillet, C., Keller, B., Rogers, J., Stein, N., IWGSC whole-genome assembly principal investigators:, Pozniak, C. J., Stein, N., Choulet, F., Distelfeld, A., Eversole, K., Poland, J., Rogers, J., Ronen, G., Sharpe, A. G., Whole-genome sequencing and assembly:, Pozniak, C., Ronen, G., Stein, N., Barad, O., Baruch, K., Choulet, F., Keeble-Gagnere, G., Mascher, M., Sharpe, A. G., Ben-Zvi, G., Josselin, A.-A., Hi-C data-based scaffolding:, Stein, N., Mascher, M., Himmelbach, A., Whole-genome assembly quality control and analyses:, Choulet, F., Keeble-Gagnere, G., Mascher, M., Rogers, J., Balfourier, F., Gutierrez-Gonzalez, J., Hayden, M., Josselin, A.-A., Koh, C., Muehlbauer, G., Pasam, R. K., Paux, E., Pozniak, C. J., Rigault, P., Sharpe, A. G., Tibbits, J., Tiwari, V., Pseudomolecule assembly:, Choulet, F., Keeble-Gagnere, G., Mascher, M., Josselin, A.-A., Rogers, J., Ref; Seq genome structure and gene analyses:, Spannagl, M., Choulet, F., Lang, D., Gundlach, H., Haberer, G., Keeble-Gagnere, G., Mayer, K. F. X., Ormanbekova, D., Paux, E., Prade, V., Simkova, H., Wicker, T., Automated annotation:, Choulet, F., Spannagl, M., Swarbreck, D., Rimbert, H., Felder, M., Guilhot, N., Gundlach, H., Haberer, G., Kaithakottil, G., Keilwagen, J., Lang, D., Leroy, P., Lux, T., Mayer, K. F. X., Twardziok, S., Venturini, L., Manual gene curation:, Appels, R., Rimbert, H., Choulet, F., Juhasz, A., Keeble-Gagnere, G., Subgenome comparative analyses:, Choulet, F., Spannagl, M., Lang, D., Abrouk, M., Haberer, G., Keeble-Gagnere, G., Mayer, K. F. X., Wicker, T., Transposable elements:, Choulet, F., Wicker, T., Gundlach, H., Lang, D., Spannagl, M., Phylogenomic analyses:, Lang, D., Spannagl, M., Appels, R., Fischer, I., Transcriptome analyses and RNA-seq data:, Uauy, C., Borrill, P., Ramirez-Gonzalez, R. H., Appels, R., Arnaud, D., Chalabi, S., Chalhoub, B., Choulet, F., Cory, A., Datla, R., Davey, M. W., Hayden, M., Jacobs, J., Lang, D., Robinson, S. J., Spannagl, M., Steuernagel, B., Tibbits, J., Tiwari, V., van Ex, F., Wulff, B. B. H., Whole-genome methylome:, Pozniak, C. J., Robinson, S. J., Sharpe, A. G., Cory, A., Histone mark analyses:, Benhamed, M., Paux, E., Bendahmane, A., Concia, L., Latrasse, D., BAC chromosome MTP IWGSC-Bayer Whole-Genome Profiling (WGP) tags:, Rogers, J., Jacobs, J., Alaux, M., Appels, R., Bartos, J., Bellec, A., Berges, H., Dolezel, J., Feuillet, C., Frenkel, Z., Gill, B., Korol, A., Letellier, T., Olsen, O.-A., Simkova, H., Singh, K., Valarik, M., van der Vossen, E., Vautrin, S., Weining, S., Chromosome LTC mapping and physical mapping quality control:, Korol, A., Frenkel, Z., Fahima, T., Glikson, V., Raats, D., Rogers, J., RH mapping:, Tiwari, V., Gill, B., Paux, E., Poland, J., Optical mapping:, Dolezel, J., Cihalikova, J., Simkova, H., Toegelova, H., Vrana, J., Recombination analyses:, Sourdille, P., Darrier, B., Gene family analyses:, Appels, R., Spannagl, M., Lang, D., Fischer, I., Ormanbekova, D., Prade, V., CBF gene family:, Barabaschi, D., Cattivelli, L., Dehydrin gene family:, Hernandez, P., Galvez, S., Budak, H., NLR gene family:, Steuernagel, B., Jones, J. D. G., Witek, K., Wulff, B. B. H., Yu, G., PPR gene family:, Small, I., Melonek, J., Zhou, R., Prolamin gene family:, Juhasz, A., Belova, T., Appels, R., Olsen, O.-A., WAK gene family:, Kanyuka, K., King, R., Stem solidness (SSt1) QTL team:, Nilsen, K., Walkowiak, S., Pozniak, C. J., Cuthbert, R., Datla, R., Knox, R., Wiebe, K., Xiang, D., Flowering locus C (FLC) gene team:, Rohde, A., Golds, T., Genome size analysis:, Dolezel, J., Cizkova, J., Tibbits, J., Micro; RNA and t; RNA annotation:, Budak, H., Akpinar, B. A., Biyiklioglu, S., Genetic maps and mapping:, Muehlbauer, G., Poland, J., Gao, L., Gutierrez-Gonzalez, J., NDaiye, A., BAC libraries and chromosome sorting:, Dolezel, J., Simkova, H., Cihalikova, J., Kubalakova, M., Safar, J., Vrana, J., BAC pooling, BAC library repository, and access:, Berges, H., Bellec, A., Vautrin, S., IWGSC sequence and data repository and access:, Alaux, M., Alfama, F., Adam-Blondon, A.-F., Flores, R., Guerche, C., Letellier, T., Loaec, M., Quesneville, H., Physical maps and BAC-based sequences:, 1; A BAC sequencing and assembly:, Pozniak, C. J., Sharpe, A. G., Walkowiak, S., Budak, H., Condie, J., Ens, J., Koh, C., Maclachlan, R., Tan, Y., Wicker, T., 1; B BAC sequencing and assembly:, Choulet, F., Paux, E., Alberti, A., Aury, J.-M., Balfourier, F., Barbe, V., Couloux, A., Cruaud, C., Labadie, K., Mangenot, S., Wincker, P., 1; D, 4; D, and 6; D physical mapping:, Gill, B., Kaur, G., Luo, M., Sehgal, S., 2; AL physical mapping:, Singh, K., Chhuneja, P., Gupta, O. P., Jindal, S., Kaur, P., Malik, P., Sharma, P., Yadav, B., 2; AS physical mapping:, Singh, N. K., Khurana, J., Chaudhary, C., Khurana, P., Kumar, V., Mahato, A., Mathur, S., Sevanthi, A., Sharma, N., Tomar, R. S., 2; B, 2; D, 4; B, 5; BL, and 5; DL IWGSC-Bayer Whole-Genome Profiling (WGP) physical maps:, Rogers, J., Jacobs, J., Alaux, M., Bellec, A., Berges, H., Dolezel, J., Feuillet, C., Frenkel, Z., Gill, B., Korol, A., van der Vossen, E., Vautrin, S., 3; AL physical mapping:, Gill, B., Kaur, G., Luo, M., Sehgal, S., 3; DS physical mapping and BAC sequencing and assembly:, Bartos, J., Holusova, K., Plihal, O., 3; DL BAC sequencing and assembly:, Clark, M. D., Heavens, D., Kettleborough, G., Wright, J., 4; A physical mapping, BAC sequencing, assembly, and annotation:, Valarik, M., Abrouk, M., Balcarkova, B., Holusova, K., Hu, Y., Luo, M., 5; BS BAC sequencing and assembly:, Salina, E., Ravin, N., Skryabin, K., Beletsky, A., Kadnikov, V., Mardanov, A., Nesterov, M., Rakitin, A., Sergeeva, E., 6; B BAC sequencing and assembly:, Handa, H., Kanamori, H., Katagiri, S., Kobayashi, F., Nasuda, S., Tanaka, T., Wu, J., 7; A physical mapping and BAC sequencing:, Appels, R., Hayden, M., Keeble-Gagnere, G., Rigault, P., Tibbits, J., 7; B physical mapping, BAC sequencing, and assembly:, Olsen, O.-A., Belova, T., Cattonaro, F., Jiumeng, M., Kugler, K., Mayer, K. F. X., Pfeifer, M., Sandve, S., Xun, X., Zhan, B., 7; DS BAC sequencing and assembly:, Simkova, H., Abrouk, M., Batley, J., Bayer, P. E., Edwards, D., Hayashi, S., Toegelova, H., Tulpova, Z., Visendi, P., 7; DL physical mapping and BAC sequencing:, Weining, S., Cui, L., Du, X., Feng, K., Nie, X., Tong, W., Wang, L., Figures:, Borrill, P., Gundlach, H., Galvez, S., Kaithakottil, G., Lang, D., Lux, T., Mascher, M., Ormanbekova, D., Prade, V., Ramirez-Gonzalez, R. H., Spannagl, M., Stein, N., Uauy, C., Venturini, L., Manuscript writing team:, Stein, N., Appels, R., Eversole, K., Rogers, J., Borrill, P., Cattivelli, L., Choulet, F., Hernandez, P., Kanyuka, K., Lang, D., Mascher, M., Nilsen, K., Paux, E., Pozniak, C. J., Ramirez-Gonzalez, R. H., Simkova, H., Small, I., Spannagl, M., Swarbreck, D., Uauy, C.
    American Association for the Advancement of Science (AAAS)
    Published 2018
    Staff View
    Publication Date:
    2018-08-17
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Geosciences
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Botany, Ecology, Online Only
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  3. 3
    Latest Papers from Table of Contents or Articles in Press
  4. 4
    Ramirez-Gonzalez, R. H., Borrill, P., Lang, D., Harrington, S. A., Brinton, J., Venturini, L., Davey, M., Jacobs, J., van Ex, F., Pasha, A., Khedikar, Y., Robinson, S. J., Cory, A. T., Florio, T., Concia, L., Juery, C., Schoonbeek, H., Steuernagel, B., Xiang, D., Ridout, C. J., Chalhoub, B., Mayer, K. F. X., Benhamed, M., Latrasse, D., Bendahmane, A., International Wheat Genome Sequencing Consortium, Wulff, B. B. H., Appels, R., Tiwari, V., Datla, R., Choulet, F., Pozniak, C. J., Provart, N. J., Sharpe, A. G., Paux, E., Spannagl, M., Bräutigam, A., Uauy, C., Korol, Sharpe, Juhasz, Rohde, Bellec, Distelfeld, Akpinar, Keller, Darrier, Gill, Chalhoub, Steuernagel, Feuillet, Chaudhary, Uauy, Pozniak, Ormanbekova, Xiang, Latrasse, Swarbreck, Barabaschi, Raats, Sergeeva, Salina, Paux, Cattonaro, Choulet, Kobayashi, Keeble-Gagnere, Kaur, Muehlbauer, Kettleborough, Yu, Simkova, Gundlach, Berges, Rimbert, Budak, Handa, Small, Bartos, Rogers, Dolezel, Keilwagen, Poland, Melonek, Jacobs, Wright, Jones, Gutierrez-Gonzalez, Eversole, Nilsen, Mayer, Kanyuka, Singh, Gao, Concia, Venturini, Cattivelli, Spannagl, Mascher, Hayden, Abrouk, Alaux, Luo, Valarik, Benhamed, Singh, Sharma, Guilhot, Ravin, Stein, Olsen, Gupta, Khurana, Chhuneja, Bayer, Borrill, Leroy, Rigault, Sourdille, Hernandez, Flores, Ramirez-Gonzalez, King, Knox, Appels, Zhou, Walkowiak, Galvez, Biyiklioglu, Nasuda, Sandve, Chalabi, Weining, Sehgal, Jindal, Belova, Letellier, Wicker, Tanaka, Fahima, Barbe, Tiwari, Kumar, Tan
    American Association for the Advancement of Science (AAAS)
    Published 2018
    Staff View
    Publication Date:
    2018-08-17
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Geosciences
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Botany, Online Only
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  5. 5
    Appels, R. ; Williams, A.F.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0005-2787
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  6. 6
    Hilliker, A.J. ; Appels, R.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0014-4827
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  7. 7
    Appels, R. ; Bolund, L. ; Goto, S. ; Ringertz, N.R.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0014-4827
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  8. 8
    Appels, R. ; Steffensen, D.M. ; Craig, S.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0014-4827
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  9. 9
    Appels, R. ; Bell, P.B. ; Ringertz, N.R.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0014-4827
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  10. 10
    Brutlag, D. ; Appels, R. ; Dennis, E.S. ; Peacock, W.J.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0022-2836
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  11. 11
    Appels, R. ; Tallroth, E. ; Appels, D.M. ; Ringertz, N.R.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0014-4827
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  12. 12
    Appels, R. ; Ringertz, N.R.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0045-6039
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  13. 13
    Clarke, B.C. ; Hobbs, M. ; Skylas, D. ; Appels, R.
    Springer
    Published 2000
    Staff View
    ISSN:
    1438-7948
    Keywords:
    Wheat Endosperm cDNA Genomics
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Notes:
    Abstract. This paper describes the construction and characterisation of a cDNA library from wheat endosperm tissue during the early stages of grain filling. Developing wheat endosperm tissue was characterised with respect to standard measures including dry weight, cytological appearance and timing of expression of major sources of mRNA such as the seed storage protein genes. In addition, the full complement of proteins present at mid-endosperm development was examined using 2D-electrophoretic techniques. Based on this characterisation, endosperm from the developing grain 8–12 days post-anthesis was chosen for isolating mRNA and preparing cDNA. At this stage in development the mRNA population is not yet dominated by the accumulation of mRNA from seed storage protein genes. A cDNA library, not normalised, containing a high percentage of full length cDNA clones was constructed and 4,319 clones sequenced ("single-pass"). Partitioning of the cDNA sequences into gene families and singletons provided the basis for quantifying the accumulation of sequence classes relative to the total number of sequences determined. The accumulation of gene families/singletons was not linear. However, mathematical modeling of the data suggested that the maximum number of different genes expressed is within the range of 4,500–8,000 (detailed in the Appendix). If an average is taken of these extremes, approximately 27% of the gene products were visible as proteins in the 2D-electrophoretic analysis. Analysis of a functional class of genes relevant to wheat grain end-use, namely the glutenin/gliadin seed storage protein class of genes, revealed a new category of gene characterised by a distinctive N-terminal domain and a reduced central repetitive domain.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  14. 14
    Staff View
    ISSN:
    1432-0886
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Abstract Cloned highly repeated DNA sequences were used to investigate the origins of W. virgo. The chromosomal and genomic organization of these sequences in the parthenogenetic grasshopper W. virgo and its sexual relatives indicate that W. virgo has had two independent origins. Data from the cloned sequences together with that from rapidly renaturing DNA are consistent with a hybridization event between two sexual species for each origin of the parthenogenetic species. Previously published data on C-banding and other karyotypic features (White and Contreras 1981) strengthen the dual origin conclusion. — The cloned DNA sequences, pWv 1 and pWv 5, have differentiated northern and southern races in the sexual species P196. The southern race appears to have hybridized with another sexual species, P169, to give rise to the Boulder/Zanthus clones of W. virgo. The northern race of P196 may have crossed with a species similar to P169 to give rise to the remaining W. virgo clones which are now present in both eastern and western Australia. White (1980) proposed that the origin of W. virgo was in western Australia and that the eastern populations were established by migration. Consistent with this hypothesis is our finding that the cloned DNA sequences have identical genomic and chromosomal organisation in populations of W. virgo in the two disjunct areas.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  15. 15
    Staff View
    ISSN:
    1432-0886
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Abstract The chromosomal locations of ribosomal DNA in wheat, rye and barley have been determined by in situ hybridization using high specific activity 125I-rRNA. The 18S-5.8S-26S rRNA gene repeat units in hexaploid wheat (cv. Chinese Spring) are on chromosomes 1B, 6B and 5D. In rye (cv. Imperial) the repeat units occur at a single site on chromosome 1R(E), while in barley (cv. Clipper) they are on both the chromosomes (6 and 7) which show secondary constrictions. In wheat and rye the major 5S RNA gene sites are close to the cytological secondary constrictions where the 18S-5.8S-26S repeating units are found, but in barley the site is on a chromosome not carrying the other rDNA sequences. — Restriction enzyme and R-loop analyses showed the 18S-5.8S-26S repeating units to be approximately 9.5 kb long in wheat, 9.0 kb in rye and barley to have two repeat lengths of 9.5 kb and 10 kb. Electron microscopic and restriction enzyme data suggest that the two barley forms may not be interpersed. Digestion with EcoR1 gave similar patterns in the three species, with a single site in the 26S gene. Bam H1 digestion detected heterogeneity in the spacer regions of the two different repeats in barley, while in rye and wheat heterogeneity was shown within the 26S coding sequence by an absence of an effective Bam H1 site in some repeat units. EcoR1 and Bam H1 restriction sites have been mapped in each species. — The repeat unit of the 5S RNA genes was approximately 0.5 kb in wheat and rye and heterogeneity was evident. The analysis of the 5S RNA genes emphasizes the homoeology between chromosomes 1B of wheat and 1R of rye since both have these genes in the same position relative to the secondary constriction. In barley we did not find a dominant monomer repeat unit for the 5S genes.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  16. 16
    Steffensen, Dale M. ; Appels, R. ; Peacock, W. J.
    Springer
    Published 1981
    Staff View
    ISSN:
    1432-0886
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Abstract In situ hybridization using 3H-RNA probes has been used to localize the sequences found in two satellites of density 1.705 g/cc and 1.672 g/ cc to specific sites within the chromosomal complement. A detailed analysis of the sites on the X chromosome was carried out using the scute series of inversions to relate the heterochromatic breakpoint relative to the location of the sequence on this chromosome. It has also been possible to establish the order of arrangement of 1.705 and 1.672 DNA at the heterochromaticeuchromatic junction on chromosome 3(R). A mitotic map is provided. The Tm of hybrids formed in situ showed that the hybrids were representative of the sequences being analyzed. The two satellites also were traced through a number of purification procedures to show that a covalent linkage may be likely between the 1.705 g/cc and 1.672 g/cc satellite as predicted from in situ hybridization analyses.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  17. 17
    Appels, R. ; Dennis, E. S. ; Smyth, D. R. ; Peacock, W. J.
    Springer
    Published 1981
    Staff View
    ISSN:
    1432-0886
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Abstract Rye DNA sequences renaturing with a C0t 〈0.02 mol·sec/l, are largely undigested by the restriction enzyme HindIII. These HindIII-spared sequences are mostly located in telomeric heterochromatin. When digested with EcoRI* and cloned into the EcoRI site of pBR 325, these sequences yielded clones of two classes when hybridized to a probe of rapidly renaturing DNA. One class contains a DNA sequence which is a major constituent of the telomeric heterochromatic blocks, while the other is a minor component of the highly repeated DNA of the genome. The major component was sequenced, its chromosomal distribution mapped using wheat-rye addition lines and its distribution in meiotic prophase nuclei determined. The minor component is present in significant amounts in wheat as well as in rye and is localized at the terminal heterochromatic regions of three rye chromosomes but not in the major blocks of heterochromatin.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  18. 18
    Hilliker, Arthur J. ; Appels, R.
    Springer
    Published 1982
    Staff View
    ISSN:
    1432-0886
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Abstract In Drosophila melanogaster X chromosome heterochromatin (Xh) constitutes the proximal 40% of the X chromosome DNA and contains a number of genetic elements with homologous sites on the Y chromosome, one of which is well defined, namely, the bobbed locus, the repetitive structural locus for the 18S and 28S rRNAs. This report presents the localisation of specific repeated DNA sequences within Xh and the employment of this sequence map in constructing new chromosomes to analyse the nature of the heterochromatin surrounding the rDNA region. Repeated sequences were located relative to inversion breakpoints which differentiate Xh cytogenetically. When the rDNA region was manipulated to be in a position in the chromosome so that it was without the Xh which normally surrounds it, the following obser-vations were made, (i) The rDNA region of Xh is intrinsically hetero-chromatic, remaining genetically active and yet possessing major heterochromatic properties even in the absence of the flanking heterochromatin regions, (ii) The size of the deletion removing the portion of Xh normally located distal to the rDNA region affected the dominance relationship between the X and Y nucleolar organizers (activity/endoreduplication assayed in male salivary glands). The X rDNA without any flanking heterochromatin was dominant over Y rDNA while the presence of some Xh allowed both the X and Y rDNA to be utilized, (iii) Enhancement of the position effect variegation on the white locus was demonstrated to occur as a result of the Xh deletions generated. EMS mutagenesis studies argue that the regions of Xh flanking the rDNA region contain no vital loci despite the fact that they strongly effect gene expression in some genotypes. This is consistent with early studies using X-ray mutagenesis (Lindsley et al., 1960). The pleiotropic effects of deleting specific regions of Xh is discussed in relation to the possible influence of heterochromatin on the organisation of the functional interphase nucleus.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  19. 19
    Baum, M. ; Appels, R.
    Springer
    Published 1991
    Staff View
    ISSN:
    1432-0886
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Conclusions The evolution of chromosome 1R has resulted in a structure with genes that are similar enough, qualitatively and quantitatively, to those in wheat to allow substitution for wheat chromosomes. The sequences dispersed between the genes, and those arranged tandemly in large blocks, have however undergone major quantitative changes (and possibly qualitative changes as well). Amplification events since the time that wheat and rye have been separated in an evolutionary sense have generated arrays of repetitive sequence families that characterize the rye chromosomes (including 1R) and distinguish them from wheat chromosomes. The genetic mapping of chromosome 1R at the level of DNA has provided a range of probes for the study of 1R chromosome segments as they are manipulated in commercial wheat cultivars. The extensive utilization of chromosome 1R as a source of disease resistance genes in wheat implies that rye genes are normally expressed in a wheat background. This is, however, not always the case and a particularly well studied example is the suppression of rRNA gene expression (reviewed in Applels et al. 1986a). These isolated examples of modified expression of rye genes in a wheat background are presumably the result of evolutionary change in the rye promoter regions resulting in their reduced competitiveness when combined with wheat genes in a common cytoplasmic environment. The cytoplasm of wheat plants carrying rye chromosome fragments would be dominated by protein molecules adapted to wheat promoters.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  20. 20
    Clarke, B. C. ; Mukai, Y. ; Appels, R.
    Springer
    Published 1996
    Staff View
    ISSN:
    1432-0886
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Abstract. This paper describes a detailed sequence analysis of the ω-secalin gene array at the Sec-1 locus on the short arm of chromosome 1 of rye. The analysis shows that the genes are separated by 8 kb of spacer sequence and that the gene/spacer units are arranged in a head to tail fashion. The boundaries of the array are identified, and a fragment containing the majority of the genes in the array is separated by PFG analysis. The sequence data of one 9.2 kb gene unit have been determined, and because of the similarity of the gene units within the array these data provide a detailed sequence analysis of 140 kb of the Sec-1 locus. Fluorescence in situ hybridization, using lambda clones isolated for the structural analysis, identifies the position of the array on the rye chromosomes relative to the 5S rRNA genes.
    Type of Medium:
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    Articles: DFG German National Licenses