Simultaneous discrimination of the three genomes in hexaploid wheat by multicolor fluorescence in situ hybridization using total genomic and highly repeated DNA probes

Common wheat, Triticum aestivum, is an allohexaploid species consisting of three different genomes (A, B, and D). The three genomes were simultaneously discriminated with different colors. Biotinylated total genomic DNA of the diploid A genome progenitor Triticum urartu, digoxigenin-labeled total genomic DNA of the diploid D genome progenitor Aegilops squarrosa, and nonlabeled total genomic DNA of one of the possible B genome progenitors Ae. speltoides were hybridized in situ to metaphase chromosome spreads of Triticum aestivum cv. Chinese Spring. For detection, only two fluorochromes, fluorescein and rhodamine, were used. The A, B, and D genomes were simultaneously detected by their yellow, brown, and orange fluorescence, respectively. The genomic fluorescence in situ hybridization pattern of chromosome 4A of cv. Chinese Spring wheat showed that the distal 32% of the long arm was derived from a B genome chromosome. Furthermore, by using two highly repeated sequence probes, pSc 119.2 and pAsl, and two fluorochromes simultaneously, we were able to identify all B and D genome chromosomes and chromosomes 1A, 4A, and 5A of wheat.Key words: common wheat, in situ hybridization, multicolor fluorescence.

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Detection of maize DNA sequences amplified in wheat

Genome ◽

10.1139/g95-124 ◽

1995 ◽

Vol 38 (5) ◽

pp. 946-950 ◽

Cited By ~ 1

Author(s):

Juan Zhang ◽

Bernd Friebe ◽

Bikram S. Gill

Keyword(s):

Triticum Aestivum ◽

Zea Mays ◽

In Situ Hybridization ◽

Dna Sequences ◽

Hexaploid Wheat ◽

Chinese Spring ◽

Genomic Dna ◽

Genomic In Situ Hybridization ◽

Metaphase Chromosomes

Genomic in situ hybridization to somatic metaphase chromosomes of hexaploid wheat cv. Chinese Spring using biotinylated maize genomic DNA as a probe revealed the existence of amplified maize DNA sequences in five pairs of chromosomes. The in situ hybridization sites were located on chromosomes 1A, 7A, 2B, 3B, and 7B. One pair of in situ hybridization sites was also observed in hexaploid oat. The locations and sizes of in situ hybridization sites varied among progenitor species.Key words: Triticum aestivum, Zea mays, shared DNA sequences, genomic in situ hybridization.

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Molecular analyses of a repetitive DNA sequence in wheat (Triticum aestivum L.)

Genome ◽

10.1139/g99-143 ◽

2000 ◽

Vol 43 (3) ◽

pp. 556-563 ◽

Cited By ~ 7

Author(s):

P P Ueng ◽

A Hang ◽

H Tsang ◽

J M Vega ◽

L Wang ◽

...

Keyword(s):

Triticum Aestivum ◽

In Situ Hybridization ◽

Long Terminal Repeat ◽

Fluorescence In Situ Hybridization ◽

Repetitive Sequence ◽

Genomic Dna ◽

Repeat Unit ◽

Terminal Repeat ◽

Genomic Clones

A repetitive sequence designated WE35 was isolated from wheat genomic DNA. This sequence consists of a 320-bp repeat unit and represents approximately 0.002% of the total wheat DNA. It is unidirectionally distributed either continuously or discretely in the genome. Ladder-like banding patterns were observed in Southern blots when the wheat genomic DNA was restricted with endonuclease enzymes EcoRI, HincII, NciI, and NdeI, which is characteristic for tandemly organized sequences. Two DNA fragments in p451 were frequently associated with the WE35 repetitive unit in a majority of λ wheat genomic clones. A 475-bp fragment homologous to the 5'-end long terminal repeat (LTR) of cereal retroelements was also found in some λ wheat genomic clones containing the repetitive unit. Physical mapping by fluorescence in situ hybridization (FISH) indicated that one pair of wheat chromosomes could be specifically detected with the WE35 positive probe p551. WE35 can be considered a chromosome-specific repetitive sequence. This repetitive unit could be used as a molecular marker for genetic, phylogenetic, and evolutionary studies in the tribe Triticeae.Key words: repetitive sequence, genomic DNA, Triticum aestivum, fluorescence in situ hybridization, long terminal repeat.

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Molecular evidence for the origin and evolution of chromosome 4A in polyploidy wheats

Canadian Journal of Genetics and Cytology ◽

10.1139/g85-036 ◽

1985 ◽

Vol 27 (2) ◽

pp. 246-250 ◽

Cited By ~ 22

Author(s):

A. Lane Rayburn ◽

B. S. Gill

Keyword(s):

In Situ Hybridization ◽

Chinese Spring ◽

Diploid Species ◽

Aegilops Speltoides ◽

Molecular Evidence ◽

Wheat Evolution ◽

D Genome ◽

Origin And Evolution ◽

B Genome

The chromosomes of polyploid Triticum species and the putative donor diploid species were analyzed by in situ hybridization with a repeated DNA sequence clone pSc 119 isolated from rye and also found in wheat. In Triticum aestivum cv. Chinese Spring, chromosome 4A showed one terminal site in the short arm and one terminal and two interstitial sites of hybridization in the long arm. Triticum turgidum contained a 4A chromosome identical to 'Chinese Spring' with respect to hybridization sites. Chromosome 4A of the timopheevi wheats differed from 4A of 'Chinese Spring' in that the site of the sequence on the short arm was subterminal rather than terminal. Of the A-, B-, and D-genome progenitor species, only potential B-genome donors Aegilops speltoides and Aegilops sharonensis each showed a chromosome with hybridization sites similar to 4A. This suggested that 4A belongs to the B genome. Moreover, with regard to this sequence, chromosome 4A has undergone only minor changes during the evolution of the polyploid wheats.Key words: wheat evolution, in situ hybridization, biotin labeling.

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Simultaneous painting of three genomes in hexaploid wheat by BAC-FISH

Genome ◽

10.1139/g04-042 ◽

2004 ◽

Vol 47 (5) ◽

pp. 979-987 ◽

Cited By ~ 66

Author(s):

Peng Zhang ◽

Wanlong Li ◽

Bernd Friebe ◽

Bikram S Gill

Keyword(s):

Triticum Aestivum ◽

In Situ Hybridization ◽

Transposable Elements ◽

Fluorescence In Situ Hybridization ◽

Hexaploid Wheat ◽

D Genome ◽

Bac Clones ◽

Dispersed Repeat ◽

Bac Fish

Fluorescence in situ hybridization (FISH) is widely used in the physical mapping of genes and chromosome landmarks in plants and animals. Bacterial artificial chromosomes (BACs) contain large inserts, making them amenable for FISH mapping. In our BAC-FISH experiments, we selected 56 restriction fragment length polymorphism (RFLP)-locus-specific BAC clones from the libraries of Triticum monococcum and Aegilops tauschii, which are the A- and D-genome donors of wheat (Triticum aestivum, 2n = 6x = 42), respectively. The BAC clone 676D4 from the T. monococcum library contains a dispersed repeat that preferentially hybridizes to A-genome chromosomes, and two BAC clones, 9I10 and 9M13, from the Ae. tauschii library contain a dispersed repeat that preferentially hybridizes to the D-genome chromosomes. These repeats are useful in simultaneously discriminating the three different genomes in hexaploid wheat, and in identifying intergenomic translocations in wheat or between wheat and alien chromosomes. Sequencing results show that both of these repeats are transposable elements, indicating the importance of transposable elements, especially retrotransposons, in the genome evolution of wheat.Key words: bacterial artificial chromosome (BAC), fluorescence in situ hybridization (FISH), transposable elements (TEs), wheat, Triticum aestivum.

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Genetic diversity of Asian and European common wheat lines assessed by fluorescence in situ hybridization

Genome ◽

10.1139/gen-2020-0161 ◽

2021 ◽

Author(s):

Xiu Yang ◽

Binwen Tan ◽

Yulu Yang ◽

Xiaohui Zhang ◽

Wei Zhu ◽

...

Keyword(s):

Genetic Diversity ◽

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

Common Wheat ◽

Genetic Relationships ◽

Structural Variations ◽

D Genome ◽

Western Asia ◽

Wheat Lines

Understanding the genetic diversity of wheat is important for wheat breeding and improvement. However, there have been limited attempts to evaluate wheat diversity using fluorescence in situ hybridization (FISH). In this study, the chromosomal structures of 149 wheat accessions from 13 countries located between the latitudes of 30° and 45°N, the principal growing region for wheat, were characterized using FISH with pTa535 and pSc119.2 probes. The ranges of the numbers of FISH types in the A-, B-, and D-genomes were 2–8, 3–7, and 2–4, respectively, and the average numbers in the A- and B-genomes were greater than in the D-genome. Chromosomal translocations were detected by these probes, and previously undescribed translocations were also observed. Using the FISH, the genetic relationships among the 149 common wheat lines were divided into three groups (G1, G2, and G3). G1 mainly consisted of Southern European lines, G2 consisted of most lines from Japan and some lines from Western Asia, China, and Korea, and G3 consisted of the other lines from Southern Europe and most of the lines from Western Asia, China, and Korea. FISH karyotypes of wheat chromosomes distinguished chromosomal structural variations, revealed the genetic diversity among wheat varieties. Furthermore, these results provide valuable information for the further genetic improvement of wheat in China.

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C-banding and fluorescence in situ hybridization studies of the wheat–alien hybrid 'Agrotana'

Genome ◽

10.1139/g94-066 ◽

1994 ◽

Vol 37 (3) ◽

pp. 477-481 ◽

Cited By ~ 13

Author(s):

Jie Xu ◽

R. L. Conner ◽

A. Laroche

Keyword(s):

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

Genomic Dna ◽

Chromosome Engineering ◽

C Banding ◽

Chinese Spring Wheat ◽

Mother Cells ◽

Alien Chromatin ◽

Chromosome Segments

'Agrotana', a wheat-alien hybrid (2n = 56), is a potential source of resistance to common root rot, stem rust, wheat streak mosaic virus, and the wheat curl mite. However, the origin of 'Agrotana', reported to be durum wheat × Agropyron trichophorum (pubescent wheatgrass), is uncertain. The objective of this investigation was to determine the chromosome constitution of 'Agrotana' using C-banding and fluorescence in situ hybridization techniques. The F1 hybrid of 'Agrotana' × 'Chinese Spring' wheat showed 7 I + 21 II in 14.9% of the pollen mother cells, evidence of the presence of the A, B, and D genomes in 'Agrotana'. The hybrid had 16 heavily C-banded chromosomes, namely 4A, and 1-7B of wheat, and a translocation that probably involved wheat chromosomes 2A and 2D. In situ hybridization using biotinylated genomic DNA of Ag. trichophorum cv. Greenleaf blocked with CS DNA failed to identify the alien chromosomes in 'Agrotana', indicating that the alien chromosomes were not likely derived from pubescent wheatgrass. In situ hybridization using labelled wheat genomic DNA blocked with 'Agrotana' DNA revealed that 'Agrotana' had 40 wheat, 14 alien, and 2 (a pair) wheat–alien translocated chromosomes. There was no homology between wheat and the alien chromosomes or chromosome segments involved in the wheat–alien recombinant. Two of the seven pairs of alien chromosomes were homoeologous to each other. The ability to identify alien chromatin in wheat using labelled wheat DNA instead of labelled alien DNA will be particularly useful in chromosome engineering of wheat germplasms having alien chromatin of unknown origin.Key words: wheat–alien hybrid, C-banding, fluorescence in situ hybridization, labelled wheat DNA as probe.

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