Oligo-painting and GISH reveal meiotic chromosome biases and increased meiotic stability in synthetic allotetraploid Cucumis ×hytivus with dysploid parental karyotypes

Abstract Background Meiosis of newly formed allopolyploids frequently encounter perturbations induced by the merging of divergent and hybridizable genomes. However, to date, the meiotic properties of allopolyploids with dysploid parental karyotypes have not been studied in detail. The allotetraploid Cucumis ×hytivus (HHCC, 2n = 38) was obtained from interspecific hybridization between C. sativus (CC, 2n = 14) and C. hystrix (HH, 2n = 24) followed by chromosome doubling. The results of this study thus offer an excellent opportunity to explore the meiotic properties of allopolyploids with dysploid parental karyotypes. Results In this report, we describe the meiotic properties of five chromosomes (C5, C7, H1, H9 and H10) and two genomes in interspecific hybrids and C. ×hytivus (the 4th and 14th inbred family) through oligo-painting and genomic in situ hybridization (GISH). We show that 1) only two translocations carrying C5-oligo signals were detected on the chromosomes C2 and C4 of one 14th individual by the karyotyping of eight 4th and 36 14th plants based on C5- and C7-oligo painting, and possible cytological evidence was observed in meiosis of the 4th generation; 2) individual chromosome have biases for homoeologous pairing and univalent formation in F1 hybrids and allotetraploids; 3) extensive H-chromosome autosyndetic pairings (e.g., H-H, 25.5% PMCs) were observed in interspecific F1 hybrid, whereas no C-chromosome autosyndetic pairings were observed (e.g. C-C); 4) the meiotic properties of two subgenomes have significant biases in allotetraploids: H-subgenome exhibits higher univalent and chromosome lagging frequencies than C-subgenome; and 5) increased meiotic stability in the S14 generation compared with the S4 generation, including synchronous meiosis behavior, reduced incidents of univalent and chromosome lagging. Conclusions These results suggest that the meiotic behavior of two subgenomes has dramatic biases in response to interspecific hybridization and allopolyploidization, and the meiotic behavior harmony of subgenomes is a key subject of meiosis evolution in C. ×hytivus. This study helps to elucidate the meiotic properties and evolution of nascent allopolyploids with the dysploid parental karyotypes.

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An assessment of chromosomal rearrangements in neopolyploids of Lilium hybrids

Genome ◽

10.1139/g10-018 ◽

2010 ◽

Vol 53 (6) ◽

pp. 439-446 ◽

Cited By ~ 18

Author(s):

Songlin Xie ◽

Nadeem Khan ◽

M. S. Ramanna ◽

Lixin Niu ◽

Agnieszka Marasek-Ciolakowska ◽

...

Keyword(s):

Interspecific Hybrids ◽

Mitotic Chromosome ◽

Chromosome Doubling ◽

Meiotic Chromosome ◽

Chromosomal Rearrangements ◽

2N Gametes ◽

Backcross Progeny ◽

Genomic In Situ Hybridization ◽

Meiotic Chromosomes

Two types of newly induced polyploids (neopolyploids) of Lilium hybrids were monitored for the occurrence of chromosomal rearrangements through genomic in situ hybridization (GISH) technique. One of the populations was obtained through crossing an allotriploid Longiflorum × Oriental hybrid (LLO) with an allotetraploid Longiflorum × Trumpet hybrid (LLTT), both of which were derived from somatic chromosome doubling. The other type of allopolyploid population was derived from meiotic chromosome doubling in which numerically unreduced (2n) gametes from two different interspecific hybrids, namely, Longiflorum × Asiatic (LA) and Oriental × Asiatic (OA), were used to get backcross progeny with the Asiatic parents. GISH clearly discriminated the three constituent genomes (L, T, and O) in the complements of the progeny obtained from mitotic chromosome doubling. A total of 26 individuals were analyzed from this population and there was no evidence of chromosomal rearrangements. However, in the case of meiotically doubled allopolyploid progeny, considerable frequencies of chromosomal rearrangements were observed through GISH. The so-called chromosomal rearrangements in meiotic polyploids are the result of homoeologous recombination rather than translocations. Furthermore, evidence for the occurrence of meiotic recombination in the LA hybrids has been confirmed with GISH on meiotic chromosomes. Thus, there was evidence that neopolyploids of Lilium hybrids did not possess any noticeable chromosome rearrangements.

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Genomic affinities of Zea luxurians, Z. diploperennis, and Z. perennis: Meiotic behavior of their F1 hybrids and genomic in situ hybridization (GISH)

Genome ◽

10.1139/g99-032 ◽

1999 ◽

Vol 42 (5) ◽

pp. 993-1000 ◽

Cited By ~ 15

Author(s):

L Poggio ◽

V Confalonieri ◽

C Comas ◽

G Gonzalez ◽

C A Naranjo

Keyword(s):

In Situ Hybridization ◽

Repetitive Sequences ◽

Basic Chromosome Number ◽

Genomic In Situ Hybridization ◽

F1 Hybrids ◽

Meiotic Behavior ◽

Mitotic Chromosomes ◽

Cytological Evidence ◽

Zea Luxurians

Since 1987 cytological evidence has arisen in our laboratory, pointing to x = 5 as the original basic chromosome number of maize and its related wild species. This paper deals with the analysis of the meiotic behavior of F1 hybrids Zea luxurians × Z. diploperennis (2n = 20) and Z. luxurians × Z. perennis (2n = 30). In the first hybrid the most frequent configuration was 8ll + 4l and in the latter was 5lll + 5ll + 5l. Applying GISH (genomic in situ hybridization) to mitotic chromosomes of Z. luxurians we found that DAPI (4', 6-diamidino-2-phenylindole) positive bands located in all telomeric regions of this species did not hybridize with either Z. perennis or Z. diploperennis genomic probe. Therefore, Z. luxurians has a repetitive sequence that can be used in fluorescent staining to identify its chromosomes. When GISH was employed on metaphase I of the 2n = 30 hybrid, all the univalents showed distinctive telomeres of Z. luxurians, while the bivalents did not present any signal. These findings show that the formation of bivalent-univalent configurations is not a random event. The bivalents tend to be spatially separated and are very often observed forming an independent group of 5II. Finally, trivalents were composed by one chromosome labeled in its telomeric regions, and two smaller and unlabeled ones. The use of chromosome markers of Z. luxurians demonstrated to be a good step forward in interpreting the nature of meiotic configurations in 2n = 30 Zea spp. hybrids. They can help to clarify the relationship between genomes and provide a useful addition to the taxonomic classification in the genus Zea.Key Words: Zea hybrids, evolution, cytogenetics, repetitive sequences, heterochromatic knobs.

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Visualizing Meiotic Chromosome Pairing and Segregation in Interspecific Hybrids of Rice by Genomic in situ Hybridization

Rice Science ◽

10.1016/j.rsci.2020.11.008 ◽

2021 ◽

Vol 28 (1) ◽

pp. 69-80

Author(s):

Liu Mao-Sen ◽

Tseng Shih-Hsuan ◽

Chen Ting-Chu ◽

Chung Mei-Chu

Keyword(s):

In Situ Hybridization ◽

Chromosome Pairing ◽

Interspecific Hybrids ◽

Meiotic Chromosome ◽

Genomic In Situ Hybridization ◽

Meiotic Chromosome Pairing

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Genomic in situ hybridization in Brassica amphidiploids and interspecific hybrids

Theoretical and Applied Genetics ◽

10.1007/s001220050699 ◽

1997 ◽

Vol 95 (8) ◽

pp. 1320-1324 ◽

Cited By ~ 94

Author(s):

R. J. Snowdon ◽

W. Köhler ◽

W. Friedt ◽

A. Köhler

Keyword(s):

In Situ Hybridization ◽

Interspecific Hybrids ◽

Genomic In Situ Hybridization

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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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