Fluorescence in situ hybridization mapping of Avena sativa L. cv. SunII and its monosomic lines using cloned repetitive DNA sequences

Fluorescent in situ hybridization (FISH) employing multiple probes was used with mitotic or meiotic chromosome spreads of Avena sativa L. cv. SunII and its monosomic lines to produce physical chromosome maps. The probes used were Avena strigosa pAs120a (which hybridizes exclusively to A-genome chromosomes), Avena murphyi pAm1 (which hybridizes exclusively to C-genome chromosomes), A. strigosa pAs121 (which hybridizes exclusively to A- and D-genome chromosomes), and the wheat rDNA probes pTa71 and pTa794. Simultaneous and sequential FISH employing two-by-two combinations of these probes allowed the unequivocal identification and genome assignation of all chromosomes. Ten pairs were found carrying intergenomic translocations: (i) between the A and C genomes (chromosome pair 5A); (ii) between the C and D genomes (pairs 1C, 2C, 4C, 10C, and 16C); and (iii) between the D and C genomes (pairs 9D, 11D, 13D, and 14D). The existence of a reciprocal intergenomic translocation (10C14D) is also proposed. Comparing these results with those of other hexaploids, three intergenomic translocations (10C, 9D, and 14D) were found to be unique to A. sativa cv. SunII, supporting the view that 'SunII' is genetically distinct from other hexaploid Avena species and from cultivars of the A. sativa species. FISH mapping using meiotic and mitotic metaphases facilitated the genomic and chromosomal identification of the aneuploid chromosome in each monosomic line. Of the 18 analyzed, only 11 distinct monosomic lines were actually found, corresponding to 5 lines of the A genome, 2 lines of the C genome, and 4 lines of the D genome. The presence or absence of the 10C14D interchange was also monitored in these lines.Key words: Avena sativa, monosomics, FISH mapping, genomic identification, intergenomic translocations.

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Chromosomal organization of a sequence related to LTR-like elements of Ty1-copia retrotransposons in Avena species

Genome ◽

10.1139/g99-007 ◽

1999 ◽

Vol 42 (4) ◽

pp. 706-713 ◽

Cited By ~ 10

Author(s):

Concha Linares ◽

Antonio Serna ◽

Araceli Fominaya

Keyword(s):

In Situ Hybridization ◽

Diploid Species ◽

D Genome ◽

Specific Sequence ◽

Chromosomal Organization ◽

Intergenomic Translocations ◽

A Genome ◽

Slot Blot Analysis ◽

Copia Retrotransposons

A repetitive sequence, pAs17, was isolated from Avena strigosa (As genome) and characterized. The insert was 646 bp in length and showed 54% AT content. Databank searches revealed its high homology to the long terminal repeat (LTR) sequences of the specific family of Ty1-copia retrotransposons represented by WIS2-1A and Bare. It was also found to be 70% identical to the LTR domain of the WIS2-1A retroelement of wheat and 67% identical to the Bare-1 retroelement of barley. Southern hybridizations of pAs17 to diploid (A or C genomes), tetraploid (AC genomes), and hexaploid (ACD genomes) oat species revealed that it was absent in the C diploid species. Slot-blot analysis suggested that both diploid and tetraploid oat species contained 1.3 × 104 copies, indicating that they are a component of the A-genome chromosomes. The hexaploid species contained 2.4 × 104 copies, indicating that they are a component of both A- and D-genome chromosomes. This was confirmed by fluorescent in situ hybridization analyses using pAs17, two ribosomal sequences, and a C-genome specific sequence as probes. Further, the chromosomes involved in three C-A and three C-D intergenomic translocations in Avena murphyi (AC genomes) and Avena sativa cv. Extra Klock (ACD genomes), respectively, were identified. Based on its physical distribution and Southern hybridization patterns, a parental retrotransposon represented by pAs17 appears to have been active at least once during the evolution of the A genome in species of the Avena genus.Key words: chromosomal organization, in situ hybridization, intergenomic translocations, LTR sequence, oats.

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Genomic in situ hybridization differentiates between A/D- and C-genome chromatin and detects intergenomic translocations in polyploid oat species (genus Avena)

Genome ◽

10.1139/g94-087 ◽

1994 ◽

Vol 37 (4) ◽

pp. 613-618 ◽

Cited By ~ 98

Author(s):

E. N. Jellen ◽

B. S. Gill ◽

T. S. Cox

Keyword(s):

In Situ Hybridization ◽

Avena Sativa ◽

Genomic In Situ Hybridization ◽

Hybridization Pattern ◽

C Banding ◽

Intergenomic Translocations ◽

C Genome ◽

Total Dna

The genomic in situ hybridization (GISH) technique was used to discriminate between chromosomes of the C genome and those of the A and A/D genomes in allopolyploid oat species (genus Avena). Total biotinylated DNA from A. strigosa (2n = 2x = 14, AsAs genome) was mixed with sheared, unlabelled total DNA from A. eriantha (2n = 2x = 14, CpCp) at a ratio of 1:200 (labelled to unlabelled). The resulting hybridization pattern consisted of 28 mostly labelled and 14 mostly unlabelled chromosomes in the hexaploids. Attempts to discriminate between chromosomes of the A and D genomes in A. sativa (2n = 6x = 42, AACCDD) were unsuccessful using GISH. At least eight intergenomic translocation segments were detected in A. sativa 'Ogle', several of which were not observed in A. byzantina 'Kanota' (2n = 6x = 42, AACCDD) or in A. sterilis CW 439-2 (2n = 6x = 42, AACCDD). At least five intergenomic translocation segments were observed in A. maroccana CI 8330 'Magna' (2n = 4x = 28, AACC). In both 'Ogle' and 'Magna', positions of most of these translocations matched with C-banding patterns.Key words: Avena sativa, oat, in situ hybridization, C-banding, Avena macrostachya.

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Isolation of A/D and C genome specific dispersed and clustered repetitive DNA sequences from Avena sativa

Genome ◽

10.1139/g01-148 ◽

2002 ◽

Vol 45 (2) ◽

pp. 431-441 ◽

Cited By ~ 17

Author(s):

Evgueni V Ananiev ◽

M Isabel Vales ◽

Ronald L Phillips ◽

Howard W Rines

Keyword(s):

In Situ Hybridization ◽

Repetitive Dna ◽

Dna Sequences ◽

Avena Sativa ◽

Genomic Dna ◽

Repetitive Sequences ◽

Repeated Sequences ◽

C Genome ◽

Copy Dna

DNA gel-blot and in situ hybridization with genome-specific repeated sequences have proven to be valuable tools in analyzing genome structure and relationships in species with complex allopolyploid genomes such as hexaploid oat (Avena sativa L., 2n = 6x = 42; AACCDD genome). In this report, we describe a systematic approach for isolating genome-, chromosome-, and region-specific repeated and low-copy DNA sequences from oat that can presumably be applied to any complex genome species. Genome-specific DNA sequences were first identified in a random set of A. sativa genomic DNA cosmid clones by gel-blot hybridization using labeled genomic DNA from different Avena species. Because no repetitive sequences were identified that could distinguish between the A and D gneomes, sequences specific to these two genomes are refereed to as A/D genome specific. A/D or C genome specific DNA subfragments were used as screening probes to identify additional genome-specific cosmid clones in the A. sativa genomic library. We identified clustered and dispersed repetitive DNA elements for the A/D and C genomes that could be used as cytogenetic markers for discrimination of the various oat chromosomes. Some analyzed cosmids appeared to be composed entirely of genome-specific elements, whereas others represented regions with genome- and non-specific repeated sequences with interspersed low-copy DNA sequences. Thus, genome-specific hybridization analysis of restriction digests of random and selected A. sativa cosmids also provides insight into the sequence organization of the oat genome.Key words: oat, cosmid library, in situ hybridization.

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The use of double fluorescence in situ hybridization to physically map the positions of 5S rDNA genes in relation to the chromosomal location of 18S–5.8S–26S rDNA and a C genome specific DNA sequence in the genus Avena

Genome ◽

10.1139/g96-068 ◽

1996 ◽

Vol 39 (3) ◽

pp. 535-542 ◽

Cited By ~ 63

Author(s):

Concha Linares ◽

Juan González ◽

Esther Ferrer ◽

Araceli Fominaya

Keyword(s):

In Situ Hybridization ◽

Dna Sequence ◽

Diploid Species ◽

5S Rdna ◽

Rdna Genes ◽

26S Rdna ◽

A Genome ◽

Rdna Loci ◽

C Genome

A physical map of the locations of the 5S rDNA genes and their relative positions with respect to 18S–5.8S–26S rDNA genes and a C genome specific repetitive DNA sequence was produced for the chromosomes of diploid, tetraploid, and hexaploid oat species using in situ hybridization. The A genome diploid species showed two pairs of rDNA loci and two pairs of 5S loci located on both arms of one pair of satellited chromosomes. The C genome diploid species showed two major pairs and one minor pair of rDNA loci. One pair of subtelocentric chromosomes carried rDNA and 5S loci physically separated on the long arm. The tetraploid species (AACC genomes) arising from these diploid ancestors showed two pairs of rDNA loci and three pairs of 5S loci. Two pairs of rDNA loci and 2 pairs of 5S loci were arranged as in the A genome diploid species. The third pair of 5S loci was located on one pair of A–C translocated chromosomes using simultaneous in situ hybridization with 5S rDNA genes and a C genome specific repetitive DNA sequence. The hexaploid species (AACCDD genomes) showed three pairs of rDNA loci and six pairs of 5S loci. One pair of 5S loci was located on each of two pairs of C–A/D translocated chromosomes. Comparative studies of the physical arrangement of rDNA and 5S loci in polyploid oats and the putative A and C genome progenitor species suggests that A genome diploid species could be the donor of both A and D genomes of polyploid oats. Key words : oats, 5S rDNA genes, 18S–5.8S–26S rDNA genes, C genome specific repetitive DNA sequence, in situ hybridization, genome evolution.

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Neocentromere-mediated Chromosome Movement in Maize

The Journal of Cell Biology ◽

10.1083/jcb.139.4.831 ◽

1997 ◽

Vol 139 (4) ◽

pp. 831-840 ◽

Cited By ~ 62

Author(s):

Hong-Guo Yu ◽

Evelyn N. Hiatt ◽

Annette Chan ◽

Mary Sweeney ◽

R. Kelly Dawe

Keyword(s):

In Situ Hybridization ◽

Dna Sequences ◽

Average Rate ◽

Meiotic Chromosome ◽

Chromosome Movement ◽

Microtubule Depolymerization ◽

Chromosome 10 ◽

Chromosome Congression ◽

Or Genes

Neocentromere activity is a classic example of nonkinetochore chromosome movement. In maize, neocentromeres are induced by a gene or genes on Abnormal chromosome 10 (Ab10) which causes heterochromatic knobs to move poleward at meiotic anaphase. Here we describe experiments that test how neocentromere activity affects the function of linked centromere/kinetochores (kinetochores) and whether neocentromeres and kinetochores are mobilized on the spindle by the same mechanism. Using a newly developed system for observing meiotic chromosome congression and segregation in living maize cells, we show that neocentromeres are active from prometaphase through anaphase. During mid-anaphase, normal chromosomes move on the spindle at an average rate of 0.79 μm/min. The presence of Ab10 does not affect the rate of normal chromosome movement but propels neocentromeres poleward at rates as high as 1.4 μm/min. Kinetochore-mediated chromosome movement is only marginally affected by the activity of a linked neocentromere. Combined in situ hybridization/immunocytochemistry is used to demonstrate that unlike kinetochores, neocentromeres associate laterally with microtubules and that neocentromere movement is correlated with knob size. These data suggest that microtubule depolymerization is not required for neocentromere motility. We argue that neocentromeres are mobilized on microtubules by the activity of minus end–directed motor proteins that interact either directly or indirectly with knob DNA sequences.

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The genomic identification of some monosomics of Avena sativa L. cv. Sun II using genomic in situ hybridization

Genome ◽

10.1139/g95-094 ◽

1995 ◽

Vol 38 (4) ◽

pp. 747-751 ◽

Cited By ~ 30

Author(s):

J. M. Leggett ◽

G. S. Markhand

Keyword(s):

In Situ Hybridization ◽

Avena Sativa ◽

Genomic Dna ◽

Diploid Species ◽

Genomic In Situ Hybridization ◽

Chromosome Translocations ◽

C Genome

Genomic in situ hybridization using total genomic DNA extracted from the C genome diploid species Avena eriantha (2n = 2x = 14, genome CpCp) was used to identify monosomics (2n = 6x − 1 = 41) of the constituent genomes of the hexaploid cultivated oat A. sativa L. cv. Sun II (2n = 6x = 42, genomes AACCDD). The results demonstrate 3 AD/C and 6 C/AD chromosome translocations, indicate that five of the missing monosomics are derived from the C genome, and show that there are duplicates within the partial monosomic series. Chromosome polymorphisms between some monosomic lines are also demonstrated.Key words: Avena, monosomics, genomic in situ hybridization, genomic identification.

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Use of Genomic in Situ Hybridization (GISH) to Track Genetic Introgression in Onion

HortScience ◽

10.21273/hortsci.32.3.513b ◽

1997 ◽

Vol 32 (3) ◽

pp. 513B-513

Author(s):

Anfu Hou ◽

Ellen B. Peffley

Keyword(s):

In Situ Hybridization ◽

Dna Sequences ◽

Genomic In Situ Hybridization ◽

Genetic Introgression ◽

A Genome

Introgression of genes in species crosses can be observed morphologically in backcrossed or selfed progenies, but the phenotype does not give information about the movement of DNAs. Cytogenetic markers allow for visualization of specific DNAs in a genome. Few cytogenetic markers are available in onion to monitor the introgression of DNA in species crosses. Genomic in situ hybridization (GISH) provides a way to locate unique DNA sequences contributed by parents. We are using GISH to monitor the movement of DNAs from A. fistulosum into A. cepa. Results of experiments using A. fistulosum as probe DNA, and A. cepa as blocking DNA will be reported. Also presented are hybridization sites observed in F1BC3 progeny of the GISH.

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New evidence concerning the genome designations of the AC(DC) tetraploid Avena species

10.1101/2020.10.02.323345 ◽

2020 ◽

Author(s):

Honghai Yan ◽

Zichao Ren ◽

Di Deng ◽

Kehan Yang ◽

Chuang Yang ◽

...

Keyword(s):

Repetitive Dna ◽

Dna Sequences ◽

Rrna Gene ◽

Repetitive Dna Sequences ◽

D Genome ◽

Intergenomic Translocations ◽

5S Rrna Gene ◽

New Evidence ◽

Robust Evidence

AbstractThe tetraploid Avena species in the section Pachycarpa Baum, including A. insularis, A. maroccana, and A. murphyi, are thought to be involved in the evolution of hexaploid oats; however, their genome designations are still being debated. Repetitive DNA sequences play an important role in genome structuring and evolution, so understanding the chromosomal organization and distribution of these sequences in Avena species could provide valuable information concerning genome evolution in this genus. In this study, the chromosomal organizations and distributions of six repetitive DNA sequences (including three SSR motifs (TTC, AAC, CAG), one 5S rRNA gene fragment, and two oat A and C genome specific repeats) were investigated using non-denaturing fluorescence in situ hybridization (ND-FISH) in the three tetraploid species mentioned above and in two hexaploid oat species. Preferential distribution of the SSRs in centromeric regions was seen in the A and D genomes, whereas few signals were detected in the C genomes. Some intergenomic translocations were observed in the tetraploids; such translocations were also detected between the C and D genomes in the hexaploids. These results provide robust evidence for the presence of the D genome in all three tetraploids, strongly suggesting that the genomic constitution of these species is DC and not AC, as had been thought previously.

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Chromosomal distribution of a repeated DNA sequence from C-genome heterochromatin and the identification of a new ribosomal DNA locus in the Avena genus

Genome ◽

10.1139/g95-071 ◽

1995 ◽

Vol 38 (3) ◽

pp. 548-557 ◽

Cited By ~ 39

Author(s):

Araceli Fominaya ◽

Gregorio Hueros ◽

Yolanda Loarce ◽

Esther Ferrer

Keyword(s):

In Situ Hybridization ◽

Satellite Dna ◽

Repeated Dna ◽

Chromosomal Distribution ◽

Genome Chromosome ◽

26S Rdna ◽

A Genome ◽

C Genome ◽

Repeated Dna Sequence

Satellite DNA specific to the oat C genome was sequenced and located on chromosomes of diploid, tetraploid, and hexaploid Avena ssp. using in situ hybridization. The sequence was present on all seven C genome chromosome pairs and hybridized to the entire length of each chromosome, with the exception of the terminal segments of some chromosome pairs. Three chromosome pairs belonging to the A genome showed hybridization signals near the telomeres of their long arms. The existence of intergenomic chromosome rearrangements and the deletions of the repeated units are deduced from these observations. The number of rDNA loci (18S–5.8S–26S rDNA) was determined for the tetraploid and hexaploid oat species. Simultaneous in situ hybridization with the satellite and rDNA probes was used to assign the SAT chromosomes of these species to their correct genomes.Key words: oats, satellite DNA, rDNA, in situ hybridization, genome evolution.

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