Genomic affinities in Turnera (subseries Turnera, Turneraceae) inferred by in situ hybridization techniques

Subseries Turnera comprises a polyploid complex with ploidy levels ranging from diploid (2n = 2x = 10) to octoploid (2n = 8x = 40). The use of fluorescent in situ hybridization greatly improved the knowledge of the karyotypes of Turnera species by detecting and mapping rDNA sites. Interspecific variability in the number of sites was detected, but not in correlation with the ploidy level. A chromosome pair with a strong hybridization signal was always visible and this signal corresponded to the secondary constriction detectable by conventional techniques. Genomic in situ hybridization experiments combined with information on meiotic pairing in species and interspecific hybrids revealed that homologies detected by molecular analysis are greater than those detected by chromosome pairing. This suggests that the formation of the allopolyploids could involve species more closely related than previously assumed. Despite the molecular affinity among the genomes, the meiotic pairing is probably controlled by specific genes that restrict homeologous pairing in polyploids.

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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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Monocentric chromosomes in Juncus (Juncaceae) and implications for the chromosome evolution of the family

Botanical Journal of the Linnean Society ◽

10.1093/botlinnean/boz065 ◽

2019 ◽

Vol 191 (4) ◽

pp. 475-483 ◽

Cited By ~ 6

Author(s):

Marcelo Guerra ◽

Tiago Ribeiro ◽

Leonardo P Felix

Keyword(s):

In Situ Hybridization ◽

Fluorescent In Situ Hybridization ◽

Chromosome Evolution ◽

Holocentric Chromosomes ◽

Mitotic Chromosomes ◽

Restricted Area ◽

Rdna Sites ◽

The Family ◽

Meiotic Analyses

Abstract Holocentric chromosomes are rare among angiosperms, but have been suggested to be shared by all or most of the species of Cyperaceae and Juncaceae. However, no clear demonstration of the centromere type in Juncus, the largest genus of Juncaceae, has so far been published. Thus, we conducted a detailed chromosomal investigation of four Juncus spp. aiming to identify their centromere type. Mitotic chromosomes were analysed using the fluorochromes CMA and DAPI, fluorescent in situ hybridization (FISH) with rDNA probes and immunodetection of histones H3 phosphorylated at serine 10 (H3-S10ph) and H2A phosphorylated at threonine 133 (H2A-T133ph). DAPI-stained chromosomes of all species displayed typical primary constrictions, which were not related to AT-poor CMA+ heterochromatin or rDNA sites (usually negatively stained with DAPI). Immunodetection with H3-S10ph and H2A-T133ph revealed hyperphosphorylation of pericentromeric and centromeric regions, respectively, in a restricted area, as observed in monocentric chromosomes. Meiotic analyses in J. microcephalus showed no indication of inverted meiosis, commonly found in plants with holocentric chromosomes. Since the species investigated here belong to four different sections of Juncus and all of them display typical monocentric chromosomes, it seems that this kind of centromere is common in the genus and may represent the standard centromere organization for Juncus. If Juncus has monocentric chromosomes, there is no reason to hypothesize that other genera of Juncaceae for which centromeres have not been carefully investigated have holocentric chromosomes.

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Effect of 3-Methylcholanthrene Administration on Expression of Cytochrome P-450 Isoforms Induced by Phenobarbital in Rat Hepatocytes

Journal of Histochemistry & Cytochemistry ◽

10.1177/002215549804601007 ◽

1998 ◽

Vol 46 (10) ◽

pp. 1151-1160 ◽

Cited By ~ 5

Author(s):

Kazuto Mino ◽

Jun Watanabe ◽

Shinsuke Kanamura

Keyword(s):

In Situ Hybridization ◽

Rat Hepatocytes ◽

Hybridization Signal ◽

Quantitative Immunohistochemistry ◽

Strong Hybridization ◽

Strong Hybridization Signal ◽

Cytochrome P 450

The effects of an inducer on expression of cytochrome P-450 (P-450) isoforms induced antecedently by another inducer are unknown. Thus, we examined the amount of phenobarbital (PB)-inducible P-450 isoforms (P-450 2B1/2B2) in hepatocytes from rats injected first with PB and then with 3-methylcholanthrene (MC) (PB+MC-treated animals) by quantitative immunohistochemistry. In addition, expression of P-450 2B2 mRNA was examined by in situ hybridization. In PB-treated animals, P-450 2B1/2B2 content increased in perivenular and midzonal hepatocytes. In PB+MC-treated animals, however, the PB-induced increase in 2B1/2B2 content was suppressed in perivenular hepatocytes but promoted in midzonal hepatocytes. The hybridization signal for P-450 2B2 mRNA appeared almost exclusively in perivenular hepatocytes after 24 hr of PB injection and disappeared after 48 hr of injection. In PB+MC-treated animals, however, strong hybridization signal was observed in midzonal and perivenular hepatocytes after 48 hr of PB injection. The promotion of the increase in P-450 2B1/2B2 content in midzonal hepatocytes in PB+MC-treated animals probably corresponds to the strong hybridization signal, whereas there appeared to be a divergence between the intensity of the signal and the content in perivenular hepatocytes. The results indicate that MC administration drastically influences the pattern of expression of P-450 isoforms induced by PB in perivenular and midzonal hepatocytes.

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Cytological studies of the nucleolus organizing regions in the Medicago complex: sativa–coerulea–falcata

Genome ◽

10.1139/g96-115 ◽

1996 ◽

Vol 39 (5) ◽

pp. 914-920 ◽

Cited By ~ 10

Author(s):

O. Calderini ◽

F. Pupilli ◽

P. D. Cluster ◽

A. Mariani ◽

S. Arcioni

Keyword(s):

In Situ Hybridization ◽

Silver Nitrate ◽

Fluorescent In Situ Hybridization ◽

Diploid Species ◽

2N Gametes ◽

Root Tip ◽

Medicago Falcata ◽

Rdna Sites ◽

Silver Nitrate Staining

A cytological examination of the nucleolus organizing regions (NORs) of three species from the Medicago sativa complex was conducted to evaluate the structural and functional evolution of the ribosomal RNA (rRNA) loci that encode the 18S, 5.8S, and 26S rRNAs. Mitotic chromosomes in root-tip preparations from tetraploid M. sativa and diploids Medicago coerulea and Medicago falcata were visualized by four methods that provide new data. Fluorescent in situ hybridization using the M. sativa 18S gene as probe localized the structural rDNA to the constricted regions of the satellited chromosomes only. Chromomycin A3 (CMA3) staining and 4′,6-diamidino-2-phenylindole (DAPI) staining identified these chromosomal segments as the most GC-rich regions in the alfalfa karyotype. Medicago falcata exhibited fewer DAPI bands and chromocenters than did M. sativa and M. coerulea. Positive silver nitrate staining showed that all four rDNA regions in M. sativa (located in two chromosome pairs) and both rDNA sites in both diploid species remain transcriptionally active. Counts of nucleoli confirmed that all rDNA regions are independently capable of nucleolus organization. Thus, the number of active NORs in M. sativa is double the number found in M. coerulea or M. falcata. Consequently, if M. sativa originated from sexual hybridization of 2n gametes involving one or both diploid species, no major reorganization or loss of structural or functional rDNA loci has occurred. Key words : alfalfa evolution, CMA3 banding, DAPI banding, fluorescent in situ hybridization, silver nitrate staining.

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An analysis of meiotic pairing in trisomy 21 oocytes using fluorescent in situ hybridization

Cytogenetic and Genome Research ◽

10.1159/000014956 ◽

1998 ◽

Vol 80 (1-4) ◽

pp. 48-53 ◽

Cited By ~ 14

Author(s):

E.Y. Cheng ◽

Y.-J. Chen ◽

G. Bonnet ◽

S.M. Gartler

Keyword(s):

In Situ Hybridization ◽

Trisomy 21 ◽

Fluorescent In Situ Hybridization ◽

Meiotic Pairing

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Localization of 45S and 5S rDNA sites and karyotype of Chrysanthemum and its related genera by fluorescent in situ hybridization

Biochemical Systematics and Ecology ◽

10.1016/j.bse.2015.08.006 ◽

2015 ◽

Vol 62 ◽

pp. 164-172 ◽

Cited By ~ 6

Author(s):

Xiangyu Qi ◽

Fei Zhang ◽

Zhiyong Guan ◽

Haibin Wang ◽

Jiafu Jiang ◽

...

Keyword(s):

In Situ Hybridization ◽

Fluorescent In Situ Hybridization ◽

5S Rdna ◽

Rdna Sites

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Cytogenetic analysis of Anaecypris hispanica and its relationship with the paternal ancestor of the diploid-polyploid Squalius alburnoides complex

Genome ◽

10.1139/g06-121 ◽

2006 ◽

Vol 49 (12) ◽

pp. 1621-1628 ◽

Cited By ~ 13

Author(s):

Marta Gromicho ◽

Maria Manuela Coelho ◽

Maria Judite Alves ◽

Maria João Collares-Pereira

Keyword(s):

In Situ Hybridization ◽

Cytogenetic Analysis ◽

Fluorescent In Situ Hybridization ◽

Nuclear Genome ◽

5S Rdna ◽

Genomic Rearrangements ◽

Endangered Fish ◽

Hybrid Complex ◽

Rdna Sites

The karyotype of the endangered fish Anaecypris hispanica was revisited using advanced cytogenetic techniques to elucidate its putative relationship with the paternal ancestor of the hybrid complex Squalius alburnoides and to clarify some of the recently described cytogenetic patterns of the complex. The results of chromomycin A3 and Ag staining, as well as fluorescent in situ hybridization with 28S and 5S rDNA and the (TTAGGG)n telomeric probes, were compared with the patterns observed in specimens of the all-male nonhybrid lineage of S. alburnoides complex, which is considered to reconstitute the nuclear genome of the probably extinct paternal ancestor. Several cytogenetic features observed in A. hispanica specimens were indeed shared by S. alburnoides nuclear nonhybrid males, supporting the hypothesis of a close evolutionary link between A. hispanica and the paternal ancestor of the complex. The genomic rearrangements involving 28S rDNA sites previously described in the S. alburnoides complex and in its maternal ancestor ( S. pyrenaicus ) were not detected in A. hispanica; they are, therefore, probably due to mechanisms related to hybridization and polyploidy.

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Detection of ribosomal DNA sites in lentil and chickpea by fluorescent in situ hybridization

Genome ◽

10.1139/g94-101 ◽

1994 ◽

Vol 37 (4) ◽

pp. 713-716 ◽

Cited By ~ 23

Author(s):

S. Abbo ◽

T. E. Miller ◽

S. M. Reader ◽

R. P. Dunford ◽

I. P. King

Keyword(s):

In Situ Hybridization ◽

Fluorescent In Situ Hybridization ◽

Lens Culinaris ◽

Organizer Region ◽

Nucleolus Organizer Region ◽

Nucleolus Organizer ◽

Rdna Sites ◽

In The Wild ◽

Wild Lentil

Hybridization sites of an rDNA probe coding for the 18S, 5.8S, and 26S genes were detected on lentil and chickpea somatic chromosomes using fluorescent in situ hybridization. One pair of hybridization sites was detected in cultivated lentil Lens culinaris L. and wild lentil L. orientalis (Boiss.) Hand.-Mazz., and in both the hybridization sites of the ribosomal probe correspond to the secondary constriction. In cultivated chickpea Cicer arietinum three pairs of rDNA sites were detected and in the wild C. reticulatum two pairs were detected. The karyotypic relationship between the cultivated C. arietinum and its wild progenitor C. reticulatum is discussed.Key words: chickpea, lentil, rDNA sites, nucleolus organizer region, fluorescent in situ hybridization, primer-mediated in situ hybridization.

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