Distribution of FISH oligo-5S rDNA and oligo-(AGGGTTT)3 in Hibiscus mutabilis L.

Genome ◽  
2021 ◽  
pp. 1-10
Author(s):  
Xiaomei Luo ◽  
Zhoujian He

Hibiscus exhibits high variation in chromosome number both within and among species. The Hibiscus mutabilis L. karyotype was analyzed in detail using fluorescence in situ hybridization (FISH) with oligonucleotide probes for (AG3T3)3 and 5S rDNA, which were tested here for the first time. In total, 90 chromosomes were counted in prometaphase and metaphase, and all exhibited similarly intense (AG3T3)3 signals at both ends. (AG3T3)3 showed little variation and thus did not allow discrimination among H. mutabilis chromosomes, but its location at both ends confirmed the integrity of each chromosome, thus contributing to accurate counting of the numerous, small chromosomes. Oligo-5S rDNA marked the proximal/distal regions of six chromosomes: weak signals on chromosomes 7 and 8, slightly stronger signals on chromosomes 15 and 16, and very strong signals on chromosomes 17 and 18. Therefore, 5S rDNA could assist in chromosome identification in H. mutabilis. Metaphase chromosome lengths ranged from 3.00 to 1.18 μm, indicating small chromosomes. The ratios of longest to shortest chromosome length in prometaphase and metaphase were 2.58 and 2.54, respectively, indicating karyotype asymmetry in H. mutabilis. These results provide an exact chromosome number and a physical map, which will be useful for genome assembly and contribute to molecular cytogenetics in the genus Hibiscus.

Sociobiology ◽  
2018 ◽  
Vol 65 (4) ◽  
pp. 696 ◽  
Author(s):  
Vanderly Andrade-Souza ◽  
Olivia Maria Pereira Duarte ◽  
Cinthia Caroline Cardoso Martins ◽  
Igor Silva Santos ◽  
Márcio Gilberto Cardoso Costa ◽  
...  

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.


2017 ◽  
Vol 153 (3) ◽  
pp. 158-164 ◽  
Author(s):  
Manman Qu ◽  
Kunpeng Li ◽  
Yanli Han ◽  
Lei Chen ◽  
Zongyun Li ◽  
...  

Chromosome identification is critical for many aspects of cytogenetic research. However, for Fragaria vesca, definite identification of individual chromosomes is almost impossible because of their small size and high similarity. Here, we demonstrate that bulked oligonucleotide (oligo) probes can be used as chromosome-specific DNA markers for chromosome identification in F. vesca. Oligos specific to entire pseudochromosomes in the draft genome of F. vesca were identified and synthesized as libraries. In all, we synthesized 6 oligo libraries corresponding to 6 pseudochromosomes of F. vesca. These libraries were amplified and labeled as probes for fluorescence in situ hybridization (FISH). Two rounds of multicolor FISH analysis were sequentially conducted on the same metaphase cells with each round including 3 probe libraries, which permitted simultaneous identification of all chromosomes of F. vesca. Moreover, 45S and 5S rDNA were mapped to chromosomes 1, 2, and 7, respectively. A karyotype of metaphase chromosomes was constructed, representing the first FISH-based molecular cytogenetic karyotype of F. vesca. Our study can serve as a basis for future comparative cytogenetic research through cross-species chromosome painting using bulked oligo probes and will facilitate the application of breeding technologies that rely on the identification of chromosomes in the genus Fragaria.


Genome ◽  
1998 ◽  
Vol 41 (3) ◽  
pp. 464-467 ◽  
Author(s):  
Andrew R Leitch ◽  
K Yoong Lim ◽  
Ilia J Leitch ◽  
Michelle O'Neill ◽  
MeeLen Chye ◽  
...  

This paper reports the start of a molecular cytogenetics programme targeting the genome of the angiosperm tree species Hevea brasiliensis Muell. Arg. (rubber, 2n = 36), a major world crop about whose genetics very little is known. A metaphase karyotype of rubber is presented. In situ hybidization with the probe pTa71 for ribosomal DNA (rDNA) shows that there are four sites of probe hybidization occurring on two pairs of chromosomes called chromosomes 6 and 7 carrying sites NOR-1 and NOR-2, respectively. An examination of meristematic interphase nuclei shows that all four loci have the potential to be partially decondensed at interphase, although in many nuclei one or more loci appear fully condensed and apparently inactive. The probe pXVI revealed a single pair of chromosomes carrying 5S rDNA. The probes pTa71 and pXVI provide cytogenetic markers for three pairs of chromosomes that will be of use in genetic mapping programmes. The rubber chromosomes also have telomere sequences that hybridize with the Arabidopsis consensus sequence TTTAGGG. With the exception of the satellite region containing rDNA, which fluoresces brightly with chromomycin A3, fluorescence banding showed that there is no strong demarcation of the genome into GC- and AT-rich regions, as occurs in mammalian genomes.Key words: rubber, Hevea, genetic mapping, cytogenetics, ribosomal DNA, rDNA fluorescence banding.


2020 ◽  
Author(s):  
Francisco García-Franco ◽  
Lilian Barandica-Cañon ◽  
Ezel Galindo-Pérez ◽  
Martha Martínez García ◽  
Blanca Chávez-Sandoval

Abstract Here, we present for the first time, a method to generate homozygous segmental introgressions, by means of crosses between a pair of synmorphic species. The introgressions were monitored by the cytogenetic method of polygenic chromosome asynapses. Later the introgressions were evaluated in their capacity to produce sterility in segmental males. Also, the smallest segment with the capacity to produce sterility in segmental males was mapped by in situ hybridization of polythene chromosomes, using 8 sequences of BACs clones as probes. Finally, a bioinformatic analysis was carried out to identify the presence of particular genes. From 2 parental strains, D. buzzatii and D. koepferae, 6 simple segmental hybrid lines were generated, whose introgressing segments are distributed along chromosome 4 of these species. From the 6 simple segmental lines and by means of a new crossing strategy, the 6 respective homozygous segmental hybrid offspring were obtained, each of them carrying a specific homozygous introgression. None of the 6 heterozygous introgressions was capable of producing sterility in segmental males, while 4 of the same homozygous introgressions produced total sterility in segmental males, including in this group the two smallest introgressive segments, one of 5.03 % and the other 7.87% with respect to the total length of chromosome 4, which are located in the region F2 to F4 of the standard cytological map based on polythene chromosomes of the Drosophila Repleta group. In situ hybridization, using 8 clones from contig 1065 located along the F2 to F4 region of the physical map of D. buzzattii constructed in BACs, confirmed the precise location of the 6 clones in the chromosomal region F2 to F4 of chromosome 4 of the polygenic chromosomes of both D. buzzatii and D. mojavensis. The bioinformatic analysis of the F2 to F4 region, using the complete genetic sequence of the contig 1065 of D. buzzatti shows the presence of two predicted genes in the genomic map of D. buzzatii (g.1313.t1 and g.1314.t1), and the orthologous association of these 2 genes both with the D. moj_GI22766 gene of D. mojavensis and with the Trivet gene of D. melanogaster.


Author(s):  
O. Yu. Yurkevich ◽  
T. E. Samatadze ◽  
I. Yu. Selyutina ◽  
S. A. Zoshchuk ◽  
A. V. Amosova ◽  
...  

For the first time, a comparative karyotype analysis of closely related species Hedysarum gmelinii andH. setigerum (Hedysarum section Multicaulia) grown in Southern Siberia, has been performed by molecular cytogeneticmarkers. Chromosome numbers in karyotypes of these species were specified – 2n = 4х = 32. In some accessions, additionalB chromosomes were revealed. FISH analyses indicated high similarities in chromosome morphology and also patternsof chromosomal distributions of 45S and 5S rDNA clusters in karyotypes of H. gmelinii and H. setigerum, which confirmsthe close relationship between their genomes.


2016 ◽  
Vol 73 (2) ◽  
pp. 043
Author(s):  
Youcef Bougoutaia ◽  
Sònia Garcia ◽  
Teresa Garnatje ◽  
Meriem Kaid-Harche ◽  
Joan Vallès

Artemisia herba-alba is a largely-distributed and often landscape-dominating taxon in arid areas of the Mediterranean and Irano-Turanian regions. In Algeria, in 2010 its communities covered 10% of the steppe territory, but its populations have been subjected to overgrazing. A karyological study based on 22 populations together with a cytogenetic characterisation of this species has been performed for the first time in Algerian materials, through genome size and chromosome number determination. Fluorescence in situ hybridisation (FISH) was also used to assess the rDNA loci number and distribution in the two ploidy levels detected. The studied accessions are diploid (2n = 2x = 18 chromosomes, 6 populations) or tetraploid (2n = 4x = 36 chromosomes, 15 populations). One population, occupying a more or less central geographic position among the studied area, presented both cytotypes. Genome size reflects well the two ploidy levels, with no evidence of downsizing with polyploidy. The karyotypes are rather symmetric (2A Stebbins’ class). FISH analyses detected four signals (2 loci) in diploid and eight signals (4 loci) in tetraploid cytotypes for both ribosomal DNA genes, which present an L-type (linked) organisation, i.e. with loci from both rDNA genes colocalised. The presence of two ploidy levels suggest a genomic dynamism and even a possible differentiation underlying the morphological uniformity and despite the dramatic decrease experienced by this plant in Algeria in terms of surface coverage.


Caryologia ◽  
2021 ◽  
Vol 74 (1) ◽  
pp. 53-61
Author(s):  
Maryam Hasaninejad ◽  
Ziba Jamzad ◽  
Saeid Afsharzadeh ◽  
HojJatollah Saeidi

In this survey, the chromosome counts of eight Nepeta L. species were investigated and the karyotypic diversity among these species was studied. The examined species belong to N. cephalotes Boiss. species group, namely N. eremokosmos Rech.f., N. gloeocephala Rech. f., cephalotes Boiss., N. pungens (Bunge) Benth., N. ispahanica Boiss., N. mahanensis Jamzad & Simonds, N. hormozganica Jamzad and N. denudata Benth. collected from different habitats in Iran. The ploidy levels, karyotype formula, chromosome length range, total karyotype length, several karyotype asymmetries values and Stebbins classification were determined in this study. Results showed the same chromosome number, 2n = 2x= 18 for all studied species. The basic chromosome number for the above mentioned species are x = 9. Also, the smallest chromosome length is 1.02 μm in N. mahanensis. The largest chromosome length is 2.3 μm in N. ispahanica. The chromosomes of species were metacentric or submetacentric. According to the Stebbins classification, these species were located into three classes 1A, 2A and 3A. The chromosome numbers for six of studied species are reported here for the first time.


Author(s):  
Anna Kaczmarek ◽  
Barbara Naganowska ◽  
Bogdan Wolko

AbstractTwo molecular cytogenetics methods, PRINS (primed in situ DNA labeling) and C-PRINS (cycling PRINS), were optimized for the physical mapping of several types of DNA sequences on the mitotic chromosomes of the narrow-leafed lupin (Lupinus angustifolius L.). The fragment of the FokI element from Vicia faba was localised by indirect PRINS reaction. Two other sequences, fragments of the coding sequences of L. luteus and of L. angustifolius, were localised by indirect C-PRINS. These techniques are faster and more sensitive than FISH, and they allowed the mapping of short DNA fragments. The data obtained shows that both types of PRINS are valuable tools for chromosome identification in lupin.


2021 ◽  
Author(s):  
Yang Zhao ◽  
Honghong Deng ◽  
Yao Chen ◽  
Jihan Li ◽  
Silei Chen ◽  
...  

Abstract Background: Kiwifruit has long been regarded as ‘the king of fruits’ for its nutritional importance. However, the molecular cytogenetics of kiwifruit has long been hampered because of the large number of basic chromosome (x=29), the inherent small size and highly similar morphology of metaphase chromosomes. Fluorescence in situ hybridization (FISH) is an indispensable molecular cytogenetic technique widely used in many plant species. Herein, the effects of post-hybridization washing temperature on FISH, blocking DNA concentration on genomic in situ hybridization (GISH), extraction method on nuclei isolation and the incubation time on the DNA fiber quality in kiwifruit were evaluated.Results: The post-hybridization washing in 2×SSC solution for 3×5 min at 37 ˚C ensured high stringency and distinct specific FISH signals in kiwifruit somatic chromosomes. The use of 50× blocking DNA provided an efficient and reliable means of discriminating between chromosomes derived from in the hybrids of A. chinensis var. chinensis (2n=2x=58) × A. eriantha Benth (2n=2x=58), and inferring the participation of parental genitors. The chopping method established in the present study were found to be very suitable for preparation of leaf nuclei in kiwifruit. A high-quality linear DNA fiber was achieved by an incubation of 20 min. The physical size of 45S rDNA signals was approximately 35-40 μmm revealed by the highly reproducible fiber-FISH procedures established and optimized in this study.Conclusions: The molecular cytogenetic techniques (45S rDNA-FISH, GISH, and high-resolution fiber-FISH) for kiwifruit was for the first time established and optimized in the present study, which is the foundation for the future genomic and evolutionary studies.


2012 ◽  
Vol 61 (1-6) ◽  
pp. 179-186 ◽  
Author(s):  
Elena Truta ◽  
Gabriela Vochita ◽  
Adrian Oprea ◽  
Culita Sirbu

Abstract The description of the karyotype features and idiogram in Grindelia squarrosa (Pursh) Dunal (Asteraceae), an invasive plant in Romania, are reported here for the first time. The diploid chromosome number is 2n=2x=12, in agreement with the data published for the other species of the genus. The karyomorphological data show that the complements of the studied genotypes have small chromosomes (mean chromosome length is X̅±SE=2.56±0.10 μm, and mean length of haploid complements is X̅±SE=15.33±0.69 μm, with a range of variability comprised between 12.87-17.51 μm). The karyotypes are made up of six pairs of metacentric and submetacentric chromosomes, with an identical formula of the diploid complement: KF=2n=12=8m+ 2sm + 2sm-SAT. Satellites are located on the short arms of the chromosomes of pair III. The karyotypes show a relatively high level of intra-specific uniformity as well as similar symmetry patterns (R=1.29-1.53; TF%=38.78-41.57%; AsI%=54.54-57.61%; A1 = 0.24- 0.32; A2=0.08-0.16), belonging to 1A and 2A classes of symmetry. The small size of the chromosomes, the presence of only two chromosome morphometric types, and the preponderance of metacentrics confer a relatively high degree of symmetry to the karyotypes studied.


Sign in / Sign up

Export Citation Format

Share Document