title: Genome merger: from sequence rearrangements in triticale to their elimination in wheat-rye addition lines.
abstract: Genetic and epigenetic modifications resulting from different genomes adjusting to a common nuclear environment have been observed in polyploids. Sequence restructuring within genomes involving retrotransposon/microsatellite-rich regions has been reported in triticale. The present study uses inter-retrotransposon amplified polymorphisms (IRAP) and retrotransposon microsatellite amplified polymorphisms (REMAP) to assess genome rearrangements in wheat-rye addition lines obtained by the controlled backcrossing of octoploid triticale to hexaploid wheat followed by self-fertilization. The comparative analysis of IRAP and REMAP banding profiles, involving a complete set of wheat-rye addition lines, and their parental species revealed in those lines the presence of wheat-origin bands absent in triticale, and the absence of rye-origin and triticale-specific bands. The presence in triticale x wheat backcrosses (BC) of rye-origin bands that were absent in the addition lines demonstrated that genomic rearrangement events were not a direct consequence of backcrossing, but resulted from further genome structural rearrangements in the BC plant progeny. PCR experiments using primers designed from different rye-origin sequences showed that the absence of a rye-origin band in wheat-rye addition lines results from sequence elimination rather than restrict changes on primer annealing sites, as noted in triticale. The level of genome restructuring events evaluated in all seven wheat-rye addition lines, compared to triticale, indicated that the unbalanced genome merger situation observed in the addition lines induced a new round of genome rearrangement, suggesting that the lesser the amount of rye chromatin introgressed into wheat the larger the outcome of genome reshuffling.
authors.affiliation: Centro de Botânica Aplicada à Agricultura, Secção de Genética, Instituto Superior de Agronomia, Technical University of Lisbon, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
authors.forename: Miguel
authors.initials: M
authors.lastname: Bento
authors.forename: Perry
authors.initials: P
authors.lastname: Gustafson
authors.forename: Wanda
authors.initials: W
authors.lastname: Viegas
authors.forename: Manuela
authors.initials: M
authors.lastname: Silva
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics; D002523:Edible Grain / Q000235:genetics*; D014644:Genetic Variation; D018745:Genome, Plant; D007178:Inbreeding; D018895:Microsatellite Repeats; D010641:Phenotype; D016133:Polymerase Chain Reaction; D018626:Retroelements / Q000235:genetics*; D012434:Secale / Q000235:genetics*; D014908:Triticum / Q000235:genetics*
chemical_list: D018744:DNA, Plant; D018626:Retroelements
references.citation: Proc Natl Acad Sci U S A. 1984 Dec;81(24):8014-8
references.pmid: 6096873
references.citation: Planta. 2007 Feb;225(3):551-62
references.pmid: 17008993
references.citation: Genetics. 2008 Oct;180(2):1071-86
references.pmid: 18780739
references.citation: Cytogenet Genome Res. 2005;109(1-3):236-49
references.pmid: 15753583
references.citation: Genome. 2006 Aug;49(8):950-8
references.pmid: 17036070
references.citation: Mol Genet Genomics. 2003 Jul;269(4):464-74
references.pmid: 12768410
references.citation: Genetics. 1940 Jul;25(4):401-8
references.pmid: 17246978
references.citation: Nat Genet. 2003 Jan;33(1):102-6
references.pmid: 12483211
references.citation: J Hered. 2003 May-Jun;94(3):260-4
references.pmid: 12816968
references.citation: Genetics. 2002 Apr;160(4):1651-9
references.pmid: 11973318
references.citation: Ann Bot. 2008 Apr;101(6):825-32
references.pmid: 18252766
references.citation: Chromosome Res. 1996 Nov;4(7):517-25
references.pmid: 8939363
references.citation: Genome. 1998 Aug;41(4):535-42
references.pmid: 9796102
references.citation: Genome. 2008 Jun;51(6):399-408
references.pmid: 18521118
references.citation: Theor Appl Genet. 2005 Sep;111(5):871-8
references.pmid: 16025304
references.citation: Trends Genet. 2005 Oct;21(10):539-43
references.pmid: 16098633
references.citation: Curr Biol. 2006 Jul 11;16(13):1322-8
references.pmid: 16824920
references.citation: PLoS One. 2008;3(12):e3824
references.pmid: 19048103
references.citation: Plant Cell. 2001 Aug;13(8):1749-59
references.pmid: 11487690
references.citation: Genetics. 2008 Apr;178(4):1845-58
references.pmid: 18430920
references.citation: Genome. 2004 Oct;47(5):839-48
references.pmid: 15499398
references.citation: Plant J. 2005 Jan;41(2):221-30
references.pmid: 15634199
references.citation: Chromosome Res. 1997 Apr;5(2):125-31
references.pmid: 9146916
references.citation: Chromosome Res. 1999;7(3):205-12
references.pmid: 10421380
references.citation: PLoS One. 2008 Jan 02;3(1):e1402
references.pmid: 18167561
references.citation: J Appl Genet. 2006;47(3):221-30
references.pmid: 16877800