Possible origin of B chromosome in Dichotomius sericeus (Coleoptera)

B chromosomes have so far been described in about 80 species of Coleoptera, mainly using conventional staining analysis. In this study, 152 individuals of the dung beetle Dichotomius sericeus (Coleoptera), collected from three isolated geographical areas in the State of Pernambuco, Brazil, were analyzed to determine the frequency, prevalence, distribution, meiotic behavior, and possible B chromosome origin. The cytogenetic analysis consisted of conventional staining, C-banding, triple fluorochrome staining (CMA3/DA/DAPI), and fluorescent in situ hybridization using ribosomal DNAs (rDNAs) and H3 histone gene as probes, as well as microdissection and chromosome painting of the B chromosome. The B chromosomes were detected in all populations analyzed. Analysis revealed the heterochromatic nature and the presence of G+C-rich blocks and 18S rDNA on the B chromosome. FISH with DNA from microdissected B chromosome painted the entire extension of the B chromosome for all populations, besides the pericentromeric regions of all the autosomes, as well as the X chromosome. Finally, cross-hybridization in nine related species of Dichotomius using the microdissected B chromosome as probe did not reveal any hybridization signal. The results suggest an intraspecific and monophyletic origin for B chromosomes in D. sericeus, probably from the second or third autosomal pair.

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Satellite DNAs Unveil Clues about the Ancestry and Composition of B Chromosomes in Three Grasshopper Species

Genes ◽

10.3390/genes9110523 ◽

2018 ◽

Vol 9 (11) ◽

pp. 523 ◽

Cited By ~ 9

Author(s):

Diogo Milani ◽

Vanessa Bardella ◽

Ana Ferretti ◽

Octavio Palacios-Gimenez ◽

Adriana Melo ◽

...

Keyword(s):

In Situ Hybridization ◽

Fluorescent In Situ Hybridization ◽

B Chromosome ◽

B Chromosomes ◽

Satellite Dnas ◽

Grasshopper Species ◽

Repetitive Dnas ◽

Origin And Evolution ◽

Chromosomal Position

Supernumerary (B) chromosomes are dispensable genomic elements occurring frequently among grasshoppers. Most B chromosomes are enriched with repetitive DNAs, including satellite DNAs (satDNAs) that could be implicated in their evolution. Although studied in some species, the specific ancestry of B chromosomes is difficult to ascertain and it was determined in only a few examples. Here we used bioinformatics and cytogenetics to characterize the composition and putative ancestry of B chromosomes in three grasshopper species, Rhammatocerus brasiliensis, Schistocerca rubiginosa, and Xyleus discoideus angulatus. Using the RepeatExplorer pipeline we searched for the most abundant satDNAs in Illumina sequenced reads, and then we generated probes used in fluorescent in situ hybridization (FISH) to determine chromosomal position. We used this information to infer ancestry and the events that likely occurred at the origin of B chromosomes. We found twelve, nine, and eighteen satDNA families in the genomes of R. brasiliensis, S. rubiginosa, and X. d. angulatus, respectively. Some satDNAs revealed clustered organization on A and B chromosomes varying in number of sites and position along chromosomes. We did not find specific satDNA occurring in the B chromosome. The satDNAs shared among A and B chromosomes support the idea of putative intraspecific ancestry from small autosomes in the three species, i.e., pair S11 in R. brasiliensis, pair S9 in S. rubiginosa, and pair S10 in X. d. angulatus. The possibility of involvement of other chromosomal pairs in B chromosome origin is also hypothesized. Finally, we discussed particular aspects in composition, origin, and evolution of the B chromosome for each species.

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Recovery of a telomere-truncated chromosome via a compensating translocation in maize

Genome ◽

10.1139/g10-108 ◽

2011 ◽

Vol 54 (3) ◽

pp. 184-195 ◽

Cited By ~ 9

Author(s):

Robert T. Gaeta ◽

Tatiana V. Danilova ◽

Changzeng Zhao ◽

Rick E. Masonbrink ◽

Morgan E. McCaw ◽

...

Keyword(s):

In Situ Hybridization ◽

Fluorescent In Situ Hybridization ◽

Transgene Expression ◽

De Novo ◽

Extra Chromosome ◽

Single Gene ◽

B Chromosomes ◽

Chromosome 1 ◽

Chromosome 6

Maize-engineered minichromosomes are easily recovered from telomere-truncated B chromosomes but are rarely recovered from A chromosomes. B chromosomes lack known genes, and their truncation products are tolerated and transmitted during meiosis. In contrast, deficiency gametes resulting from truncated A chromosomes prevent their transmission. We report here a de novo compensating translocation that permitted recovery of a large truncation of chromosome 1 in maize. The truncation (trunc-1) and translocation with chromosome 6 (super-6) occurred during telomere-mediated truncation experiments and were characterized using single-gene fluorescent in situ hybridization (FISH) probes. The truncation contained a transgene signal near the end of the broken chromosome and transmitted together with the compensating translocation as a heterozygote to approximately 41%–55% of progeny. Transmission as an addition chromosome occurred in ~15% of progeny. Neither chromosome transmitted through pollen. Transgene expression (Bar) cosegregated with trunc-1 transcriptionally and phenotypically. Meiosis in T1 plants revealed eight bivalents and one tetravalent chain composed of chromosome 1, trunc-1, chromosome 6, and super-6 in diplotene and diakinesis. Our data suggest that de novo compensating translocations allow recovery of truncated A chromosomes by compensating deficiency in female gametes and by affecting chromosome pairing and segregation. The truncated chromosome can be maintained as an extra chromosome or together with the super-6 as a heterozygote.

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Comparative molecular cytogenetics in Melipona Illiger species (Hymenoptera, Apidae)

Sociobiology ◽

10.13102/sociobiology.v65i4.3480 ◽

2018 ◽

Vol 65 (4) ◽

pp. 696 ◽

Cited By ~ 2

Author(s):

Vanderly Andrade-Souza ◽

Olivia Maria Pereira Duarte ◽

Cinthia Caroline Cardoso Martins ◽

Igor Silva Santos ◽

Márcio Gilberto Cardoso Costa ◽

...

Keyword(s):

In Situ Hybridization ◽

Chromosome Number ◽

Fluorescent In Situ Hybridization ◽

Molecular Cytogenetics ◽

Fluorochrome Staining ◽

Rdna Sites ◽

Cytogenetic Studies ◽

Melipona Species ◽

Almost All

Cytogenetic studies in Melipona are scarce with only 24 species analyzed cytogenetically. Of these, six species had the rDNA sites physically mapped and characterized by Fluorescent in situ Hybridization (fish). The aim of this study was to perform karyotype analyzes on Melipona species from different regions of Brazil, with a greater sampling representative of the Amazonian fauna and using conventional, fluorochrome staining and FISH with heterologous rDNA probes. The predominant chromosome number was 2n = 18, however, the subspecies M. seminigra abunensis and M. s. pernigra showed 2n = 22 chromosomes. The karyotypes were symmetrical, however M. bicolor, M. quadrifasciata, M. flavolineata, M. fuscopilosa, M. nebulosa presented the first pair heteromorphic in length. CMA3+ blocks also exhibited heteromorphism of size and in almost all cases coincided with rDNA sites, except for M. crinita and M. nebulosa, which presented additional non-coincident CMA3+ blocks. The CMA/ rDNA sites were terminal and interstitial in species with high heterochromatic content, and pericentromeric in those species with low heterochromatic content. In addition to pointing out cytogenetic features of cytotaxonomic importance, the reorganization of the genome in Melipona is discussed.

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Identification of a pentanucleotide telomeric sequence, (TTAGG)n, in the silkworm Bombyx mori and in other insects.

Molecular and Cellular Biology ◽

10.1128/mcb.13.3.1424 ◽

1993 ◽

Vol 13 (3) ◽

pp. 1424-1432 ◽

Cited By ~ 140

Author(s):

S Okazaki ◽

K Tsuchida ◽

H Maekawa ◽

H Ishikawa ◽

H Fujiwara

Keyword(s):

Repetitive Sequence ◽

Fluorescent In Situ Hybridization ◽

Genomic Library ◽

Telomeric Sequence ◽

Cross Hybridization ◽

Telomere Sequence ◽

Eukaryotic Species ◽

Genomic Dnas ◽

Silkworm Bombyx Mori

A pentanucleotide repetitive sequence, (TTAGG)n, has been isolated from a silkworm genomic library, using cross-hybridization with a (TTNGGG)5 sequence, which is conserved among most eukaryotic telomeres. Both fluorescent in situ hybridization and Bal 31 exonuclease experiments revealed major clusters of (TTAGG)n at the telomeres of all Bombyx chromosomes. To determine the evolutionary origin of this sequence, two types of telomeric sequence, (TTAGG)5 and a hexanucleotide repetitive sequence, (TTAGGG)4, which is conserved mainly among vertebrate and several invertebrate telomeres so far examined, were hybridized to DNAs from a wide variety of eukaryotic species under highly stringent hybridization conditions. The (TTAGGG)5 oligonucleotide hybridized to genomic DNAs from vertebrates and several nonvertebrate species, as has been reported so far, but not to any DNAs from insects. On the other hand, the Bombyx type of telomere sequence, (TTAGG)n, hybridized to DNAs from 8 of 11 orders of insect species tested but not to vertebrate DNAs, suggesting that this TTAGG repetitive sequence is conserved widely among insects.

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B Chromosomes in Free-Living Flatworms of the Genus Macrostomum (Platyhelminthes, Macrostomorpha)

International Journal of Molecular Sciences ◽

10.3390/ijms222413617 ◽

2021 ◽

Vol 22 (24) ◽

pp. 13617

Author(s):

Kira S. Zadesenets ◽

Nikolay B. Rubtsov

Keyword(s):

Genome Duplication ◽

Natural Populations ◽

B Chromosome ◽

Laboratory Culture ◽

B Chromosomes ◽

Free Living ◽

Transmission Rates ◽

Supernumerary Chromosomes

B chromosomes (Bs) or supernumerary chromosomes are extra chromosomes in the species karyotype that can vary in its copy number. Bs are widespread in eukaryotes. Usually, the Bs of specimens collected from natural populations are the object of the B chromosome studies. We applied another approach analyzing the Bs in animals maintained under the laboratory conditions as lines and cultures. In this study, three species of the Macrostomum genus that underwent a recent whole-genome duplication (WGD) were involved. In laboratory lines of M. lignano and M. janickei, the frequency of Bs was less than 1%, while in the laboratory culture of M. mirumnovem, it was nearer 30%. Their number in specimens of the culture varied from 1 to 14. Mosaicism on Bs was discovered in parts of these animals. We analyzed the distribution of Bs among the worms of the laboratory cultures during long-term cultivation, the transmission rates of Bs in the progeny obtained from crosses of worms with different numbers of Bs, and from self-fertilized isolated worms. The DNA content of the Bs in M. mirumnovem was analyzed with the chromosomal in situ suppression (CISS) hybridization of microdissected DNA probes derived from A chromosomes (As). Bs mainly consisted of repetitive DNA. The cytogenetic analysis also revealed the divergence and high variation in large metacentric chromosomes (LMs) containing numerous regions enriched for repeats. The possible mechanisms of the appearance and evolution of Bs and LMs in species of the Macrostomum genus were also discussed.

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Characterization of a Maize Chromosome 4 Centromeric Sequence: Evidence for an Evolutionary Relationship With the B Chromosome Centromere

Genetics ◽

10.1093/genetics/159.1.291 ◽

2001 ◽

Vol 159 (1) ◽

pp. 291-302 ◽

Cited By ~ 6

Author(s):

Brent T Page ◽

Michael K Wanous ◽

James A Birchler

Keyword(s):

Evolutionary Relationship ◽

Bac Library ◽

B Chromosome ◽

B Chromosomes ◽

Chromosome 4 ◽

Centromeric Sequence ◽

Unit Repeat ◽

Specific Sequences

Abstract Previous work has identified sequences specific to the B chromosome that are a major component of the B centromere. To address the issue of the origin of the B and the evolution of centromere-localized sequences, DNA prepared from plants without B chromosomes was probed to seek evidence for related sequences. Clones were isolated from maize line B73 without B chromosomes by screening DNA at reduced stringency with a B centromeric probe. These clones were localized to maize centromere 4 using fluorescence in situ hybridization. They showed homology to a maize centromere-mapped sequence, to maize B chromosome centromere sequences, and to a portion of the unit repeat of knobs, which act as neocentromeres in maize. A representative copy was used to screen a BAC library to obtain these sequences in a larger context. Each of the six positive BACs obtained was analyzed to determine the nature of centromere 4-specific sequences present. Fifteen subclones of one BAC were sequenced and the organization of this chromosome 4-specific repeat was examined.

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Genomic in situ hybridization (GISH) of Tripsacum dactyloides and Zea mays ssp. mays with B chromosomes

Genome ◽

10.1139/g98-157 ◽

1999 ◽

Vol 42 (4) ◽

pp. 687-691 ◽

Cited By ~ 11

Author(s):

L Poggio ◽

V Confalonieri ◽

C Comas ◽

A Cuadrado ◽

N Jouve ◽

...

Keyword(s):

Zea Mays ◽

In Situ Hybridization ◽

B Chromosome ◽

Genomic In Situ Hybridization ◽

B Chromosomes ◽

Tripsacum Dactyloides ◽

Mitotic Chromosomes ◽

Maize Line ◽

Total Dna

Genomic affinities between Tripsacum dactyloides (2n = 72) and Zea mays ssp. mays (2n = 20 + 5 B) were analyzed through GISH (genomic in situ hybridization) to ascertain the degree of chromosome homology between the two genera. Mitotic cells of T. dactyloides were simultaneously probed with total genomic DNA from Z. mays ssp .mays (2n = 20) and with rDNA (pTA71). A disperse pattern of hybridization signal among all 72 chromosomes, corresponding to maize total DNA, and six strong fluorescent signals due to the rDNA probe hybridizing on 3 chromosome pairs of T. dactyloides were observed. Mitotic chromosomes from Z. mays ssp. mays (2n = 20 + 5 B) were hybridized with a maize line that lacked B chromosomes and knobs and with total DNA from T. dactyloides. The knobless line of maize hybridized intensely on all chromosomes except for some regions where the probe bound less. Tripsacum dactyloides bound intensely on one terminal region of each B chromosome and to some regions of chromosome pairs 2, 6, and 8. These regions are DAPI positive and coincide with regions that displayed lower affinity with the probe from the knobless maize line. The possible significance of these results is discussed briefly.Key words: Tripsacum dactyloides, Zea mays ssp. mays, maize B chromosomes, genomic in situ hybridization, GISH.

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Highly repetitive sequences in B chromosomes of Secale cereale revealed by fluorescence in situ hybridization

Genome ◽

10.1139/g94-100 ◽

1994 ◽

Vol 37 (4) ◽

pp. 709-712 ◽

Cited By ~ 25

Author(s):

Angeles Cuadrado ◽

Nicolas Jouve

Keyword(s):

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

Secale Cereale ◽

Fluorescent In Situ Hybridization ◽

Repetitive Sequences ◽

5S Rdna ◽

B Chromosomes ◽

Multigene Families ◽

Hybridization Probes

An analysis of the presence and distribution of the rye and wheat repeated sequences in rye B chromosomes was carried out by fluorescent in situ hybridization. Probes used consisted of three highly repetitive sequences from rye (pSc119.2, pSc74, and pSc34) and the multigene families for the 25S–5.8S–18S and 5S rDNA from wheat (pTa71 and pTa794, respectively). pSc74 and pSc119.2 showed hybridization signals in the telomeric regions of rye B chromosomes. The remaining DNA clones did not hybridize to the B chromosomes.Key words: Secale cereale, rye, repetitive DNA, fluorescence in situ hybridization, B chromosomes.

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B Chromosome Variants of the Grasshopper Xyleus discoideus angulatus Are Potentially Derived from Pericentromeric DNA

Cytogenetic and Genome Research ◽

10.1159/000480036 ◽

2017 ◽

Vol 152 (4) ◽

pp. 213-221 ◽

Cited By ~ 5

Author(s):

Andrezza C.S. Bernardino ◽

Diogo C. Cabral-de-Mello ◽

Carolina B. Machado ◽

Octavio M. Palacios-Gimenez ◽

Neide Santos ◽

...

Keyword(s):

Repetitive Dna ◽

Evolutionary Dynamics ◽

Chromosome Evolution ◽

Pericentromeric Region ◽

B Chromosome ◽

B Chromosomes ◽

Different Populations ◽

B Chromosome Evolution ◽

Shed Light

B chromosomes, extra elements present in the karyotypes of some eukaryote species, have been described in the grasshopper Xyleus discoideus angulatus. Although some studies have proposed an autosomal origin of the B chromosome in X. d. angulatus, little is known about its repetitive DNA composition and evolutionary dynamics. The aim of the present work was to shed light on the B chromosome evolution in X. d. angulatus by cytogenetic analysis of 27 populations from Pernambuco and Ceará states (Brazil). The frequency of B chromosomes in the different populations was determined, and chromosome measurements and fluorescence in situ hybridization (FISH) with C0t-DNA and telomeric and B chromosome sequences were performed in cells from B-carrying individuals. The results revealed variations in B chromosome prevalence among the populations and showed that some B chromosomes were smaller in certain populations. FISH produced similar patterns for the C0t-DNA probe in all hybridized individuals, whereas telomeric and B chromosome probes, obtained by microdissection, exhibited variations in their distribution. These results indicate the presence of 3 morphotypes of B chromosomes in X. d. angulatus, with variation in repetitive DNA composition during their evolution. In this species, B chromosomes have an intraspecific origin and probably arose from the pericentromeric region of A chromosomes.

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