Identification of the 5s rDNA locus in Physalis peruvianaL. chromosomes, first report

Abstract Background Fluorescence In Situ Hybridization (FISH) played an essential role to locate the ribosomal RNA genes on the chromosomes that offered a new tool to study the chromosome structure and evolution in plant. The 45S and 5S rRNA genes are independent and localized at one or more loci per the chromosome complement, their positions along chromosomes offer useful markers for chromosome discriminations. In the current study FISH has been performed to locate 45S and 5S rRNA genes on the chromosomes of nine Lathyrus species belong to five different sections, all have chromosome number 2n=14, Lathyrus gorgoni Parl, Lathyrus hirsutus L., Lathyrus amphicarpos L., Lathyrus odoratus L., Lathyrus sphaericus Retz, Lathyrus incospicuus L, Lathyrus paranensis Burkart, Lathyrus nissolia L., and Lathyrus articulates L. Results The revealed loci of 45S and 5S rDNA by FISH on metaphase chromosomes of the examined species were as follow: all of the studied species have one 45S rDNA locus and one 5S rDNA locus except L. odoratus L., L. amphicarpos L. and L. sphaericus Retz L. have two loci of 5S rDNA. Three out of the nine examined species have the loci of 45S and 5S rRNA genes on the opposite arms of the same chromosome (L. nissolia L., L. amphicarpos L., and L. incospicuus L.), while L. hirsutus L. has both loci on the same chromosome arm. The other five species showed the loci of the two types of rDNA on different chromosomes. Conclusion The detected 5S and 45S rDNA loci in Lathyrus could be used as chromosomal markers to discriminate the chromosome pairs of the examined species. FISH could discriminate only one chromosome pair out of the seven pairs in three species, in L. hirsutus L., L. nissolia L. and L. incospicuus L., and two chromosome pairs in five species, in L. paranensis Burkart, L. odoratus L., L. amphicarpos L., L. gorgoni Parl. and L. articulatus L., while it could discriminate three chromosome pairs in L. sphaericus Retz. these results could contribute into the physical genome mapping of Lathyrus species and the evolution of rDNA patterns by FISH in the coming studies in future.

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Genetic and chromosomal localization of the 5S rDNA locus in sugar beet (Beta vulgaris L.)

Genome ◽

10.1139/g97-024 ◽

1997 ◽

Vol 40 (2) ◽

pp. 171-175 ◽

Cited By ~ 11

Author(s):

J. Schondelmaier ◽

T. Schmidt ◽

C. Jung ◽

J. S. Heslop-Harrison

Keyword(s):

In Situ Hybridization ◽

Linkage Group ◽

Sugar Beet ◽

Beta Vulgaris ◽

5S Rdna ◽

Rdna Locus ◽

5S Rrna ◽

Rrna Genes ◽

Rrna Gene

A digoxigenin-labelled 5S rDNA probe containing the 5S rRNA gene and the adjacent intergenic spacer was used for in situ hybridization to metaphase and interphase chromosomes of a trisomic stock from sugar beet (Beta vulgaris L.). Three chromosomes of primary trisomic line IV (T. Butterfass. Z. Bot. 52: 46–77. 1964) revealed signals close to the centromeres. Polymorphisms of 5S rDNA repeats in a segregating population were used to map genetically the 5S rRNA genes within a cluster of markers in linkage group II of sugar beet. The concentration of genetic markers around the centromere presumably reflects the suppressed recombination frequency in centromeric regions. The correlation of physical and genetic data allowed the assignment of a linkage group to sugar beet chromosome IV according to line IV of the primary trisomics.Key words: Beta vulgaris, sugar beet, 5S rRNA, in situ hybridization, RFLPs, trisomics.

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Intraspecific polymorphism of ribosomal DNA loci number and morphology in Brachypodium pinnatum and Brachypodium sylvaticum

Cellular & Molecular Biology Letters ◽

10.2478/s11658-012-0025-4 ◽

2012 ◽

Vol 17 (4) ◽

Cited By ~ 4

Author(s):

Ewa Breda ◽

Elzbieta Wolny ◽

Robert Hasterok

Keyword(s):

5S Rdna ◽

Staining Technique ◽

Rdna Locus ◽

Chromosomal Distribution ◽

Metaphase Chromosomes ◽

Brachypodium Sylvaticum ◽

Rdna Sites ◽

Rdna Loci ◽

35S Rdna ◽

25S Rdna

AbstractThe genus Brachypodium has become the target of extensive cytomolecular studies since one of its representatives, B. distachyon, has been accepted as a model plant for temperate cereals and forage grasses. Recent preliminary studies suggested that intraspecific rDNA polymorphism can occur in at least two members of the genus, B. sylvaticum and B. pinnatum, so the aim of this study was to further analyse this phenomenon. FISH with 25S rDNA and 5S rDNA probes was performed on somatic metaphase chromosomes, supplemented by the silver staining technique which distinguishes transcriptionally active from inactive 18S-5.8S-25S rDNA loci. The number, size and chromosomal distribution of 5S rDNA loci were very constant: two loci were invariably observed in all studied diploid accessions of both species, while four 5S rDNA loci were present in the tetraploid B. pinnatum. In contrast to 5S rDNA loci, those of the 35S rDNA were more variable. Two or three loci were observed in the diploid B. pinnatum and four in tetraploid accessions. In chromosome complements of B. sylvaticum accessions from two to six 35S rDNA sites were detected. Regardless of total rDNA locus number, only two were transcriptionally active in diploid accessions of both species, while two or four were active in the tetraploid B. pinnatum. Additionally, the fluorescent CMA/DAPI banding method was used to identify the relation between rDNA sites and CMA+ bands. It was revealed that the number and chromosomal distribution of CMA+ bands are in congruence only with 35S rDNA loci which gave strong FISH signals.

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Swarm of terminal 35S in Cheirolophus (Asteraceae, Centaureinae)

Genome ◽

10.1139/g2012-041 ◽

2012 ◽

Vol 55 (7) ◽

pp. 529-535 ◽

Cited By ~ 14

Author(s):

T. Garnatje ◽

O. Hidalgo ◽

D. Vitales ◽

J. Pellicer ◽

J. Vallès ◽

...

Keyword(s):

Ribosomal Rna ◽

Canary Islands ◽

5S Rdna ◽

Rdna Locus ◽

Small Subset ◽

Terminal Position ◽

Radiation Process ◽

Cytogenetic Characterization ◽

35S Rdna ◽

Rna Genes

Island radiation constitutes a playground for species diversification, which has long fascinated researchers and still does today. Because only a small subset of taxa within the pool of island colonizers is concerned by this process, the question is raised on whether some factors could make a taxon prone to radiate. Cheirolophus is the only genus of Centaureinae subtribe to have experienced a radiation in the Canary Islands. Cytogenetic characterization through FISH of 5S and 35S ribosomal RNA genes in eight Cheirolophus species from continent and Canary Islands revealed an unusually high number of 35S predominantly at terminal position, together with a single interstitial 5S rDNA locus in all the studied taxa. Such an abundance of 35S rDNA signals is unique among Centaureinae and predates Cheirolophus arrival in Canary Islands. The possible link of the rDNA profile with radiation process is discussed through a comparison with two other case studies, the closely related Rhaponticum group and the genus Centaurea .

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Heterochromatin patterns and ribosomal DNA loci distribution in diploid and polyploid Crotalaria species (Leguminosae, Papilionoideae), and inferences on karyotype evolution

Genome ◽

10.1139/g11-034 ◽

2011 ◽

Vol 54 (9) ◽

pp. 718-726 ◽

Cited By ~ 9

Author(s):

Mateus Mondin ◽

Margarida L.R. Aguiar-Perecin

Keyword(s):

Dna Sequence ◽

Ribosomal Dna ◽

Karyotype Evolution ◽

5S Rdna ◽

Rdna Locus ◽

Variable Number ◽

Chromosome 1 ◽

Distamycin A ◽

Rdna Sites

Most Crotalaria species display a symmetric karyotype with 2n = 16, but 2n = 14 is found in Chrysocalycinae subsection Incanae and 2n = 32 in American species of the section Calycinae. Seven species of the sections Chrysocalycinae, Calycinae, and Crotalaria were analyzed for the identification of heterochromatin types with GC- and AT-specific fluorochromes and chromosomal location of ribosomal DNA loci using fluorescent in situ hybridization (FISH). A major 45S rDNA locus was observed on chromosome 1 in all the species, and a variable number of minor ones were revealed. Only one 5S rDNA locus was observed in the species investigated. Chromomycin A3 (CMA) revealed CMA+ bands colocalized with most rDNA loci, small bands unrelated to ribosomal DNA on two chromosome pairs in Crotalaria incana, and CMA+ centromeric bands that were quenched by distamycin A were detected in species of Calycinae and Crotalaria sections. DAPI+ bands were detected in C. incana. The results support the species relationships based on flower specialization and were useful for providing insight into mechanisms of karyotype evolution. The heterochromatin types revealed by fluorochromes suggest the occurrence of rearrangements in repetitive DNA families in these heterochromatic blocks during species diversification. This DNA sequence turnover and the variability in number/position of rDNA sites could be interpreted as resulting from unequal crossing over and (or) transposition events. The occurrence of only one 5S rDNA locus and the smaller chromosome size in the polyploids suggest that DNA sequence losses took place following polyploidization events.

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Chromosome polymorphism in species of the genus Hedysarum L. (Fabaceae) originated from Southern Sibеria

Проблемы ботаники Южной Сибири и Монголии ◽

10.14258/pbssm.2020003 ◽

2020 ◽

Vol 19 (1) ◽

pp. 14-16

Author(s):

O. Yu. Yurkevich ◽

T. E. Samatadze ◽

I. Yu. Selyutina ◽

S. I. Romashkina ◽

S. A. Zoshchuk ◽

...

Keyword(s):

Close Relationships ◽

5S Rdna ◽

Chromosomal Polymorphism ◽

Rdna Locus ◽

Chromosome Polymorphism ◽

45S Rdna ◽

High Similarity ◽

Southern Siberia ◽

Molecular Cytogenetic ◽

First Time

For the first time, chromosomal polymorphism in karyotypes of three species from the section Hedysarum (= syn. Gamotion) of the genus Hedysarum L. (Fabaceae) grown in Southern Siberia has been studied with the useof molecular cytogenetic markers. This comparative molecular cytogenetic analysis revealed high similarity in morphology of chromosomes in H. alpinum L., H. austrosibiricum B. Fedtsch. and H. theinum Krasnob. as well as in patterns ofdistribution of 45S and 5S rDNA loci in their karyotypes confirming their close relationships. Considerable intra-specificpolymorphism on 45S rDNA chromosome localization was detected in H. theinum. In karyotype of H. alpinum, unlikethe other two species, two chromosome pairs bearing 5S rDNA locus were observed which could be used as additionalspecies-specific markers.

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The genome structure of Arachis hypogaea (Linnaeus, 1753) and an induced Arachis allotetraploid revealed by molecular cytogenetics

Comparative Cytogenetics ◽

10.3897/compcytogen.v12i1.20334 ◽

2018 ◽

Vol 12 (1) ◽

pp. 111-140 ◽

Cited By ~ 5

Author(s):

Eliza F. de M. B. do Nascimento ◽

Bruna V. dos Santos ◽

Lara O. C. Marques ◽

Patricia M. Guimarães ◽

Ana C. M. Brasileiro ◽

...

Keyword(s):

Dna Sequences ◽

Genome Structure ◽

Diploid Species ◽

Molecular Cytogenetics ◽

5S Rdna ◽

Rdna Locus ◽

Genetic Changes ◽

Rdna Loci ◽

Cultivated Plant ◽

Fish Signal

Peanut,Arachishypogaea(Linnaeus, 1753) is an allotetraploid cultivated plant with two subgenomes derived from the hybridization between two diploid wild species,A.duranensis(Krapovickas & W. C. Gregory, 1994) andA.ipaensis(Krapovickas & W. C. Gregory, 1994), followed by spontaneous chromosomal duplication. To understand genome changes following polyploidy, the chromosomes ofA.hypogaea, IpaDur1, an induced allotetraploid (A.ipaensis×A.duranensis)4xand the diploid progenitor species were cytogenetically compared. The karyotypes of the allotetraploids share the number and general morphology of chromosomes; DAPI+bands pattern and number of 5S rDNA loci. However, one 5S rDNA locus presents a heteromorphic FISH signal in both allotetraploids, relative to corresponding progenitor. Whilst forA.hypogaeathe number of 45S rDNA loci was equivalent to the sum of those present in the diploid species, in IpaDur1, two loci have not been detected. Overall distribution of repetitive DNA sequences was similar in both allotetraploids, althoughA.hypogaeahad additional CMA3+bands and few slight differences in the LTR-retrotransposons distribution compared to IpaDur1. GISH showed that the chromosomes of both allotetraploids had preferential hybridization to their corresponding diploid genomes. Nevertheless, at least one pair of IpaDur1 chromosomes had a clear mosaic hybridization pattern indicating recombination between the subgenomes, clear evidence that the genome of IpaDur1 shows some instability comparing to the genome ofA.hypogaeathat shows no mosaic of subgenomes, although both allotetraploids derive from the same progenitor species. For some reasons, the chromosome structure ofA.hypogaeais inherently more stable, or, it has been at least, partially stabilized through genetic changes and selection.

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Molecular and cytological characterization of genomic variability in hexaploid wheat 'Lindström'

Genome ◽

10.1139/g05-050 ◽

2005 ◽

Vol 48 (5) ◽

pp. 895-904

Author(s):

Pedro Costa-Nunes ◽

Teresa Ribeiro ◽

Margarida Delgado ◽

Leonor Morais-Cecílio ◽

Neil Jones ◽

...

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Large Scale ◽

Expression Patterns ◽

5S Rdna ◽

Rdna Locus ◽

B Chromosomes ◽

Addition Line ◽

Rdna Loci

'Lindström' wheat (AABBDD + rye B chromosomes) was used to study the effects of alien chromatin introgressed into a wheat genetic background, subjecting the wheat genome to a new and transient allopolyploidisation episode. Using this experimental material, we have previously demonstrated that no large-scale chromosomal translocations occurred as a result of the genomic constitution of the addition line. However, we have shown that the presence of a number of rye B chromosomes is associated with changes in the interphase organization and expression patterns of wheat rDNA loci. We have now extended our studies to focus on a further characterization of 'Lindström' 5S rDNA loci and also on high molecular weight glutenin subunit (HMW-GS) patterns. In the process, we have uncovered an unusually large variant of the 5S rDNA locus on wheat chromosome 1B (not to be confused with rye B chromosomes) and 2 novel HMW glutenin y-type alleles. These changes are not directly related to variation in rye B chromosome number in the present material, but the fact that a new, and still segregating, 1Dy HMW-GS gene was identified indicates a recent timescale for its origin. Strikingly, the 'Lindström' 5S rDNA 1B locus integrates a unit sharing 94% homology with a rye 5S rDNA sequence, suggesting the possibility that the wheat locus was colonized by highly homologous rye sequences during the breeding of 'Lindström', when the rye and wheat genomes were together, albeit briefly, in the same nucleus.Key words: Triticum aestivum 'Lindström', allopolyploidisation, 5S rDNA, NTS, high molecular weight glutenin (HMW-GS).

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Fine organization of genomic regions tagged to the 5S rDNA locus of the bread wheat 5B chromosome

BMC Plant Biology ◽

10.1186/s12870-017-1120-5 ◽

2017 ◽

Vol 17 (S1) ◽

Cited By ~ 6

Author(s):

Ekaterina M. Sergeeva ◽

Andrey B. Shcherban ◽

Irina G. Adonina ◽

Michail A. Nesterov ◽

Alexey V. Beletsky ◽

...

Keyword(s):

Bread Wheat ◽

5S Rdna ◽

Rdna Locus ◽

Genomic Regions

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Ribosomal DNA, tri- and bi-partite pericentromeres in the permanent translocation heterozygote Rhoeo spathacea

Cellular & Molecular Biology Letters ◽

10.2478/s11658-010-0034-0 ◽

2010 ◽

Vol 15 (4) ◽

Cited By ~ 8

Author(s):

Hieronim Golczyk ◽

Robert Hasterok ◽

Marek Szklarczyk

Keyword(s):

Ribosomal Dna ◽

5S Rdna ◽

Rdna Locus ◽

45S Rdna ◽

Chromomycin A3 ◽

Specific Fluorescence ◽

Translocation Heterozygote ◽

Differential Amplification ◽

Chromosome Arm

AbstractHigh- and low-stringency FISH and base-specific fluorescence were performed on the permanent translocation heterozygote Rhoeo spathacea (2n = 12). Our results indicate that 45S rDNA arrays, rDNA-related sequences and other GC-rich DNA fraction(s) are located within the pericentromeric regions of all twelve chromosomes, usually colocalizing with the chromomycin A3-positive bands. Homogenization of the pericentromeric regions appears to result from the concerted spread of GC-rich sequences, with differential amplification likely. We found new 5S rDNA patterns, which suggest a variability in the breakpoints and in the consequent chromosome reorganizations. It was found that the large 5S rDNA locus residing on each of the 8E and 9E arms consisted of two smaller loci. On each of the two chromosome arms 3b and 4b, in addition to the major subtelomeric 5S rDNA locus, a new minor locus was found interstitially about 40% along the arm length. The arrangement of cytotogenetic landmarks and chromosome arm measurements are discussed with regard to genome repatterning in Rhoeo.

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