Identification of all homoeologous chromosomes of newly synthetic allotetraploid Cucumis × hytivus and its wild parent reveals stable subgenome structure

The genera of the tribe Triticeae (family Poaceae), constituting many economically important plants with abundant genetic resources, carry genomes such as St, H, P, and Y. The genome symbol of Roegneria C. Koch (Triticeae) is StY. The St and Y genomes are crucial in Triticeae, and tetraploid StY species participate extensively in polyploid speciation. Characterization of St and Y nonhomologous chromosomes in StY-genome species could help understand variation in the chromosome structure and differentiation of StY-containing species. However, the high genetic affinity between St and Y genome and the deficiency of a complete set of StY nonhomologous probes limit the identification of St and Y genomes and variation of chromosome structures among Roegneria species. We aimed to identify St- and Y-enhanced repeat clusters and to study whether homoeologous chromosomes between St and Y genomes could be accurately identified due to high affinity. We employed comparative genome analyses to identify St- and Y-enhanced repeat clusters and generated a FISH-based karyotype of R. grandis (Keng), one of the taxonomically controversial StY species, for the first time. We explored 4 novel repeat clusters (StY_34, StY_107, StY_90, and StY_93), which could specifically identify individual St and Y nonhomologous chromosomes. The clusters StY_107 and StY_90 could identify St and Y addition/substitution chromosomes against common wheat genetic backgrounds. The chromosomes V_St, VII_St, I_Y, V_Y, and VII_Y displayed similar probe distribution patterns in the proximal region, indicating that the high affinity between St and Y genome might result from chromosome rearrangements or transposable element insertion among V_St/Y, VII_St/Y, and I_Y chromosomes during allopolyploidization. Our results can be used to employ FISH further to uncover the precise karyotype based on colinearity of Triticeae species by using the wheat karyotype as reference, to analyze diverse populations of the same species to understand the intraspecific structural changes, and to generate the karyotype of different StY-containing species to understand the interspecific chromosome variation.

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NONSTRUCTURAL CHROMOSOME DIFFERENTIATION AMONG WHEAT CULTIVARS, WITH SPECIAL REFERENCE TO DIFFERENTIATION OF CHROMOSOMES IN RELATED SPECIES

Genetics ◽

10.1093/genetics/97.2.391 ◽

1981 ◽

Vol 97 (2) ◽

pp. 391-414

Author(s):

Jan Dvořák ◽

Patrick E McGuire

Keyword(s):

Chinese Spring ◽

Structural Changes ◽

Wheat Cultivar ◽

Chromosome Complement ◽

Triticum Aestivum L ◽

Substitution Lines ◽

Structural Differentiation ◽

Chromosome Differentiation ◽

Mother Cells ◽

Homoeologous Chromosomes

ABSTRACT Wheat cultivar Chinese Spring (Triticum aestivum L. em. Thell.) was crossed with cultivars Hope, Cheyenne and Timstein. In all three hybrids, the frequencies of pollen mother cells (PMCs) with univalents at metaphase I (MI) were higher than those in the parental cultivars. No multivalents were observed in the hybrids, indicating that the cultivars do not differ by translocations. Thirty-one Chinese Spring telosomic lines were then crossed with substitution lines in which single chromosomes of the three cultivars were substituted for their Chinese Spring homologues. The telosomic lines were also crossed with Chinese Spring. Data were collected on the frequencies (% of PMCs) of pairing of the telesomes with their homologues at MI and the regularity of pairing of the remaining 20 pairs of Chinese Spring chromosomes in the monotelodisomics obtained from these crosses. The reduced MI pairing in the intercultivar hybrids was caused primarily by chromosome differentiation, rather than by specific genes. Because the differentiation involved a large part of the chromosome complement in each hybrid, it was concluded that it could not be caused by structural changes such as inversions or translocations. In each case, the differentiation appeared to be unevenly distributed among the three wheat genomes. It is proposed that the same kind of differentiation, although of greater magnitude, differentiates homoeologous chromosomes and is responsible, together with structural differentiation, for poor chromosome pairing in interspecific hybrids.

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Homoeologous Chromosomes

Encyclopedia of Genetics, Genomics, Proteomics and Informatics ◽

10.1007/978-1-4020-6754-9_7767 ◽

2008 ◽

pp. 897-897

Keyword(s):

Homoeologous Chromosomes

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GENOME SIZE IN THREE SPECIES OF Glandularia AND THEIR HYBRIDS

Journal of Basic and Applied Genetics ◽

10.35407/bag.2019.xxx.02.05 ◽

2019 ◽

Vol 30 (2) ◽

pp. 47-54

Author(s):

M.R. Ferrari ◽

E.J. Greizerstein ◽

L. Poggio

Keyword(s):

Genome Size ◽

Dna Content ◽

High Frequency ◽

Parental Species ◽

The Other ◽

F1 Hybrids ◽

Homoeologous Pairing ◽

The Relationship ◽

Species Being ◽

Homoeologous Chromosomes

In this work the relationship between genome size of Glandularia species and the meiotic configurations found in their hybrids are discussed. Glandularia incisa (Hook.) Tronc., growing in two localities of Corrientes and Córdoba provinces, Argentina, with different ecological conditions, showed inter-population variability of the 2C-value. The DNA content found in the Corrientes locality (2.41 pg) was higher than that obtained in the Córdoba locality (2.09 pg) which has more stressful environmental conditions than the former. These values are statistically different from those that were found in Glandularia pulchella (Sweet) Tronc. from Corrientes (1.43 pg) and in Glandularia perakii Cov. et Schn from Córdoba (1.47 pg). The DNA content of the diploid F1 hybrids, G. pulchella × G. incisa and G. perakii × G. incisa, differed statistically from the DNA content of the parental species, being intermediate between them. Differences in the frequency of pairing of homoeologous chromosomes were observed in the hybrids; these differences cannot be explained by differences in genome size since hybrids with similar DNA content differ significantly in their meiotic behavior. On the other hand, the differences in the DNA content between the parental species justify the presence of a high frequency of heteromorphic open and closed bivalents and univalents with different size in the hybrids. Key words: Intra-specific DNA content variability, homoeologous pairing, heteromorphic bivalents

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THE MEIOTIC BEHAVIOR OF ANEUPOLYHAPLOIDS OF THE CULTIVATED OAT AVENA SATIVA (2n = 6x = 42)

Canadian Journal of Genetics and Cytology ◽

10.1139/g77-070 ◽

1977 ◽

Vol 19 (4) ◽

pp. 651-656 ◽

Cited By ~ 13

Author(s):

J. M. Leggett

Keyword(s):

Genetic Control ◽

Chromosome Pairing ◽

Avena Sativa ◽

Meiotic Behavior ◽

Homoeologous Chromosomes

Chromosome pairing and the frequency of secondary associations in two aneupolyhaploid plants of A. sativa are described. There was little evidence of pairing between homoeologous chromosomes in either plant. The results are discussed in relation to the genetic control of bivalent pairing in A. sativa and the possible divergence between the constituent genomes.

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Compensating ability in pollen fertilization between group-6 and -7 homoeologous chromosomes of barley and wheat.

Genes & Genetic Systems ◽

10.1266/ggs.75.251 ◽

2000 ◽

Vol 75 (5) ◽

pp. 251-258 ◽

Cited By ~ 4

Author(s):

Yu Feng Yang ◽

Yoshihiko Furuta ◽

Yukiko Fukatani ◽

A. K. M. Rafiqul Islam

Keyword(s):

Group 6 ◽

Homoeologous Chromosomes

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Genomic in situ hybridization analysis of a trigenomic hybrid involving Solanum and Lycopersicon species

Genome ◽

10.1139/g00-114 ◽

2001 ◽

Vol 44 (2) ◽

pp. 299-304 ◽

Cited By ~ 2

Author(s):

S N Haider Ali ◽

Dirk Jan Huigen ◽

M S Ramanna ◽

Evert Jacobsen ◽

Richard GF Visser

Keyword(s):

In Situ Hybridization ◽

Chromosome Doubling ◽

Genomic In Situ Hybridization ◽

Potato Genome ◽

Meiotic Chromosomes ◽

Lycopersicon Species ◽

Bridge Species ◽

Genomic Probes ◽

Homoeologous Chromosomes

A 4x potato (+) tomato fusion hybrid (2n = 4x = 48) was successfully backcrossed with a diploid Lycopersicon pennellii (2n = 2x = 24). Genomic in situ hybridization (GISH) on somatic and meiotic chromosomes confirmed that the progenies were triploids (2n = 3x = 36) and possessed three different genomes: potato, tomato, and L. pennellii. Therefore, they have been called trigenomic hybrids. Total genomic probes of both Lycopersicon species were found to hybridize mutually, whereas the potato genome was clearly differentiated. During metaphase I, bivalents were formed predominantly between tomato and L. pennellii chromosomes and the univalents of potato chromosomes were most common. Trivalents in all cases included homoeologous chromosomes of potato, tomato, and L. pennellii. However, the triploids were totally sterile as determined from extensive crossing. On chromosome doubling of triploids by shoot regeneration from callus, hexaploids (2n = 6x = 72) were obtained. Despite exhibiting clear allohexaploid behaviour by forming 36 bivalents at meiosis, these were also completely sterile like their triploid counterparts. In spite of this drawback, the prospects of chromosome pairing between potato L. pennellii and Solanum genomes does open the possibilities for bringing the two genera close.Key words: trigenomic triploids, GISH, bridge species, potato (+) tomato fusion hybrids.

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Dissection of quantitative trait loci for root characters and day length sensitivity in SynOpDH wheat (Triticum aestivum L.) bi-parental mapping population

Plant Genetic Resources ◽

10.1017/s1479262120000192 ◽

2020 ◽

Vol 18 (3) ◽

pp. 130-142

Author(s):

Harun Bektas ◽

Christopher Earl Hohn ◽

John Giles Waines

Keyword(s):

Quantitative Trait Loci ◽

Quantitative Trait ◽

Mapping Population ◽

Biomass Accumulation ◽

Triticum Aestivum L ◽

Day Length ◽

Shoot Biomass ◽

Trait Loci ◽

Root And Shoot Biomass ◽

Homoeologous Chromosomes

AbstractThe genetics of the root system is still not dissected for wheat and lack of knowledge prohibits the use of marker-assisted selection in breeding. To understand the genetic mechanism of root development, Synthetic W7984 × Opata M85 doubled-haploid (SynOpDH) mapping population was evaluated for root and shoot characteristics in PVC tubes until maturity. Two major quantitative trait loci (QTLs) for total root biomass were detected on homoeologous chromosomes 2A and 2D with logarithm of the odds scores between 6.25–10.9 and 11.8–20.86, and total phenotypic effects between 12.7–17.7 and 26.6–40.04% in 2013 and 2014, respectively. There was a strong correlation between days to anthesis and root and shoot biomass accumulation (0.50–0.81). The QTL for biomass traits on chromosome 2D co-locates with QTL for days to anthesis. The effect of extended vegetative growth, caused by photoperiod sensitivity (Ppd) genes, on biomass accumulation was always hypothesized, this is the first study to genetically support this theory.

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The MRN complex of wheat

Czech Journal of Genetics and Plant Breeding ◽

10.17221/3251-cjgpb ◽

2011 ◽

Vol 47 (Special Issue) ◽

pp. S35-S38

Author(s):

A. De Bustos ◽

R. Pérez ◽

A. Cuadrado ◽

N. Jouve

Keyword(s):

Molecular Characterization ◽

Double Strand Breaks ◽

Polyploid Species ◽

Strand Breaks ◽

Homoeologous Gene ◽

Mrn Complex ◽

Cellular Processes ◽

Homoeologous Chromosomes

The MRN complex is formed by the interaction of the products of the Mre11, Rad50 and Nbs1 genes. This complex plays a central role on repair of double-strand breaks (DSBs) and acts in a great number of cellular processes. In this study we have performed the analysis of the MRN complex in diploid and polyploid species of wheat. The molecular characterization was carried out in the diploid T. monococcum (genome A) and Ae. tauschii (genome D) and in the tetraploid T. turgidum (genomes A and B). The results obtained showed that in all cases the genes presented the main characteristics previously described in other species. A modified FISH protocol was used to locate the Rad50, Mre11 and the Nbs1 genes on the homoeologous chromosomes 5, 2 and 1, respectively. Analysis of expression showed that the hexaploid T. aestivum was the species with the higher level of expression whereas the rest of the species analysed showed no relation with its ploidy. Also, quantification of the expression of each homoeologous gene in the polyploid species evidenced in some cases a process of silencing after polyploidization. The study of the interaction between the proteins demonstrated that the interaction of proteins was not restricted to each genome, detecting interaction between proteins belonging to different genomes.

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