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Chromosoma

, Volume 103, Issue 3, pp 179–185 | Cite as

New 18S·26S ribosomal RNA gene loci: chromosomal landmarks for the evolution of polyploid wheats

  • Jiming Jiang
  • Bikram S. Gill
Original Articles

Abstract

Three new 18S·26S rRNA gene loci were identified in common wheat by sequential N-banding and in situ hybridization (ISH) analysis. Locus Nor-A7 is located at the terminal area of the long arm of 5A in both diploid and polyploid wheats. Locus Nor-B6 is located in N-band 1BL2.5 of the long arm of chromosome 1B in Triticum turgidum and Triticum aestivum. ISH sites, similar to Nor-B6, were also detected on the long arms of chromosomes 1G in Triticum timopheevii and 1S in Aegilops speltoides, but their locations on the chromosomes were different from that of Nor-B6, indicating possible chromosome rearrangements in 1GL and 1BL during evolution. The third new locus, Nor-D8, was only found on the short arm of chromosome 3D in the common wheat Wichita. The loss of rRNA gene locus Nor-A3 and gain of repetitive DNA sequence pSc119 on the terminal part of 5AS suggest a structural modification of 5AS. Comparative studies of the location of the 18S·26S rRNA gene loci in polyploid wheats and putative A and B (G) genome progenitor species support the idea that: (1) Triticum monococcum subsp. urartu is the donor of both the A and At genome of polyploid wheats. (2) Ae. speltoides is closer to the B and G genome of polyploid wheats than Aegilops longissima and is the most probable progenitor of these two genomes.

Keywords

Common Wheat Polyploid Wheat Progenitor Species Terminal Area Aegilops Speltoides 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Appels R, Gerlach WL, Dennis ES, Swift H, Peacock WJ (1980) Molecular and chromosomal organization of DNA sequences coding for ribosomal RNAs in cereals. Chromosoma 78: 293–311Google Scholar
  2. Bedbrook JR, Jones J, O'Dell M, Thompson RJ, Flavell RB (1980) A molecular description of telomeric heterochromatin in Secale species. Cell 19: 545–560Google Scholar
  3. Bhowal JG (1972) Nucleolar chromosomes in wheat. Z Pflanzenzücht 68: 253–257Google Scholar
  4. Crosby AR (1957). Nucleolar activity of lagging chromosomes in wheat. Am J Bot 44: 813–822Google Scholar
  5. Dvořák J, de Terlizzi P, Zhang H-B, Resta P (1993) The evolution of polyploid wheat: identification of the A genome donor species. Genome 36: 21–31Google Scholar
  6. Friebe B, Tuleen N, Jiang J, Gill BS (1993) Standard karyotype of Triticum longissimum and its cytogenetic relationship with T. aestivum. Genome 36: 731–742Google Scholar
  7. Gerlach WL, Bedbrook JR (1979) Cloning and characterization of ribosomal RNA genes from wheat and barley. Nucleic Acids Res 7: 1869–1885Google Scholar
  8. Gill BS, Appels R (1987) Relationships between Nor-loci from different Triticeae species. Plant Syst Evol 160: 77–89Google Scholar
  9. Gill BS, Chen PD (1987) Role of cytoplasm-specific introgression in the evolution of the polyploid wheats. Proc Natl Acad Sci USA 84: 6800–6804Google Scholar
  10. Gill BS, Friebe B, Endo TR (1991) Standard karyotype and nomenclature system for description of chromosome bands and structural aberrations in wheat (Triticum aestivum). Genome 34: 830–839Google Scholar
  11. Hutchinson J, Miller TE (1982) The nucleolar organizers of tetraploid and hexaploid wheats revealed by in situ hybridization. Theor Appl Genet 61: 285–288Google Scholar
  12. Jiang J, Gill BS (1993) Sequential chromosome banding and in situ hybridization analysis. Genome 36: 792–795Google Scholar
  13. Jiang J, Gill BS (1994) Different species-specific chromosome translocations in Triticum timopheevii and T. turgidum support diphyletic evolution of polyploid wheats. Chromosome Res 2: 59–64Google Scholar
  14. Leitch IJ, Heslop-Harrison JS (1992) Physical mapping of the 18S-5.8S-26S rRNA genes in barley by in situ hybridization. Genome 35: 1013–1018Google Scholar
  15. Leitch IJ, Heslop-Harrison JS (1993) Physical mapping of four sites of 5S rDNA sequences and one site of the α-amylase-2 gene in barley (Hordeum vulgare). Genome 36: 517–523Google Scholar
  16. Leitch IJ, Leitch AR, Heslop-Harrison JS (1991) Physical mapping of plant DNA sequences by simultaneous in situ hybridization of two differently labelled fluorescent probes. Genome 34: 329–333Google Scholar
  17. Liang GH, Wang AS, Phillips RL (1977) Control of ribosomal RNA gene multiplicity in wheat. Can J Genet Cytol 19: 425–435Google Scholar
  18. Liu CJ, Atkinson MD, Chinoy CN, Devos KM, Gale MD (1992) Nonhomoeologous translocations between group 4, 5 and 7 chromosomes within wheat and rye. Theor Appl Genet 83: 305–312Google Scholar
  19. Miller TE, Hutchinson J, Reader CM (1983) The identification of the nucleolar organizer chromosomes of diploid wheat. Theor Appl Genet 65: 145–147Google Scholar
  20. Mukai Y, Endo TR, Gill BS (1990) Physical mapping of the 5S rRNA multigene family in common wheat. J Hered 81: 290–295Google Scholar
  21. Mukai Y, Endo TR, Gill BS (1991) Physical mapping of the 18S.26S rRNA multigene family in common wheat: Identification of a new locus. Chromosoma 100: 71–78Google Scholar
  22. Naranjo T (1990) Chromosome structure of durum wheat. Theor Appl Genet 79: 397–400Google Scholar
  23. Naranjo T, Roca A, Goicoecha PG, Giraldz R (1987) Arm homoeology of wheat and rye chromosomes. Genome 29: 873–882Google Scholar
  24. Rayburn AL, Gill BS (1985) Use of biotin-labeled probes to map specific DNA sequences on wheat chromosomes. J Hered 76: 78–81Google Scholar
  25. Takumi S, Nasuda S, Liu YG, Tsunewaki K (1993) Wheat phylogeny determined by RFLP analysis of nuclear DNA. 1. Einkorn wheat. Jpn J Genet 68: 73–79Google Scholar
  26. Tsunewaki K, Ogihara Y (1983) The molecular basis of genetic diversity among cytoplasms of Triticum and Aegilops species. II. On the origin of polyploid wheat cytoplasms as suggested by chloroplast DNA restriction fragment patterns. Genetics 104: 155–171Google Scholar

Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • Jiming Jiang
    • 1
    • 2
  • Bikram S. Gill
    • 1
    • 2
  1. 1.Wheat Genetics Resource CenterKansas State UniversityManhattanUSA
  2. 2.Department of Plant PathologyKansas State UniversityManhattanUSA

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