Chromatin characterization by banding techniques, in situ hybridization, and nuclear DNA content in Cicer L. (Leguminosae)

Genome ◽  
1996 ◽  
Vol 39 (2) ◽  
pp. 258-265 ◽  
Author(s):  
I. Galasso ◽  
D. Pignone ◽  
M. Frediani ◽  
M. Maggiani ◽  
R. Cremonini
Keyword(s):  
In Situ Hybridization ◽  
Dna Content ◽  
Nuclear Dna ◽  
Hybrid Sterility ◽  
Nuclear Dna Content ◽  
5S Rdna ◽  
Rrna Genes ◽  
Evolutionary Pathway ◽  
C Banding

The karyotypes of three accessions, one each from three annual species of the genus Cicer, namely Cicer arietinum, Cicer reticulation, and Cicer echinospermum, were examined and compared using C-banding, the fluorochromes chromomycin A3, DAPI, and Hoechst 33258, in situ hybridization of the 18S–5.8S–25S and 5S rDNA sequences, and silver staining. The nuclear DNA content of the three species and the amount of heterochromatin were also determined. The results suggest an evolutionary pathway in which C. reticulatum is the ancestral species from which both C. arietinum and C. echinospermum are derived with the loss of one pair of satellites; subsequently, C. echinospermum further differentiated by the accumulation of chromosomal rearrangement(s) that gave rise to a hybrid sterility barrier. Key words : Cicer, C-banding, fluorochromes, Ag staining, rRNA genes.

Detection of a variable number of 18S-5.8S-26S and 5S ribosomal DNA loci by fluorescent in situ hybridization in diploid and tetraploid Arachis species

Genome ◽  
1999 ◽  
Vol 42 (1) ◽  
pp. 52-59 ◽  
Author(s):  
S N Raina ◽  
Y Mukai
Keyword(s):  
In Situ Hybridization ◽  
5S Rdna ◽  
Gene Families ◽  
Ribosomal Gene ◽  
Rrna Genes ◽  
Tetraploid Species ◽  
Arachis Species ◽  
26S Rdna ◽  
Rdna Loci

In order to obtain new information on the genome organization of Arachis ribosomal DNA, more particularly among A. hypogaea and its close relatives, the distribution of the 18S-5.8S-26S and 5S ribosomal RNA gene families on the chromosomes of 21 diploid and tetraploid Arachis species, selected from six of nine taxonomic sections, was analyzed by in situ hybridization with pTa71 (18S-5.8S-26S rDNA) and pTa794 (5S rDNA) clones. Two major 18S-5.8S-26S rDNA loci with intense signals were found in the nucleolus organizer regions (NOR) of each of the diploid and tetraploid species. In addition to extended signals at major NORs, two to six medium and (or) minute-sized signals were also observed. Variability in the number, size, and location of 18S-5.8S-26S sites could generally distinguish species within the same genome as well as between species with different genomes. The use of double fluorescence in situ hybridization enabled us to locate the positions of 5S rRNA genes in relation to the chromosomal location of 18S-5.8S-26S rRNA genes in Arachis chromosomes which were difficult to karyotype. Two or four 5S rDNA loci and 18S-5.8S-26S rDNA loci were generally located on different chromosomes. The tandemly repeated 5S rDNA sites were diagnostic for T and C genomes. In one species, each of B and Am genomes, the two ribosomal gene families were observed to occur at the same locus. Barring A. ipaensis and A. valida, all the diploid species had characteristic centromeric bands in all the 20 chromosomes. In tetraploid species A. hypogaea and A. monticola only 20 out of 40 chromosomes showed centromeric bands. Comparative studies of distribution of the two ribosomal gene families, and occurrence of centromeric bands in only 20 chromosomes of the tetraploid species suggests that A. villosa and A. ipaensis are the diploid progenitors of A. hypogaea and A. monticola. This study excludes A. batizocoi as the B genome donor species for A. hypogaea and A. monticola.Key words: Arachis species, 5S rRNA, 18S-5.8S-26S rRNA, in situ hybridization, evolution.

Determination of nuclear DNA content in fungi using mithramycin: vegetative diploidy in Armillaria mellea confirmed

1983 ◽  
Vol 29 (9) ◽  
pp. 1179-1183 ◽  
Author(s):  
A. L. Franklin ◽  
W. G. Filion ◽  
J. B. Anderson
Keyword(s):  
Dna Binding ◽  
Aspergillus Nidulans ◽  
Dna Content ◽  
Nuclear Dna ◽  
Nuclear Dna Content ◽  
Phytopathogenic Fungus ◽  
Armillaria Mellea ◽  
Dna Measurements

Armillaria mellea, a phytopathogenic fungus, is the only member of the Agaricales (Basidiomycetes) whose fertile vegetative phase in nature is thought to be diploid, rather than dikaryotic. To examine the vegetative ploidy of A. mellea, we used the DNA-binding antibiotic, mithramycin, for fluorometry of in situ nuclear DNA. The measurements of nuclear DNA content indicated that strains derived from single basidiospores of A. mellea were haploid and that strains derived from matings of isolates of single spores were diploid. These data confirm the results of earlier genetic experiments, which show haploidy and diploidy in unmated and mated strains, respectively. Nuclear DNA measurements in known haploid and diploid strains of Aspergillus nidulans confirmed the validity of our protocol.

C-banding and DNA content in seven species of Tenebrionidae (Coleoptera)

Genome ◽  
1989 ◽  
Vol 32 (5) ◽  
pp. 834-839 ◽  
Author(s):  
C. Juan ◽  
E. Petitpierre
Keyword(s):  
Genome Size ◽  
X Chromosome ◽  
Dna Content ◽  
Nuclear Dna ◽  
Nuclear Dna Content ◽  
C Banding ◽  
Metaphase I

The relative amount of C-banded heterochromatin varies strikingly in seven species of tenebrionid beetles, from 25 to 58%, but most species show procentric bands only. Nevertheless, Gonocephalum patruele exhibits an almost completely heterochromatic X chromosome. The nuclear DNA content of Feulgen-stained spermatids has yielded up to a threefold difference, from 0.27 to 0.86 pg, which is not completely in accordance with the amount of C-banded heterochromatin. However, the genome sizes correlate significantly with the total chromosome areas at metaphase I and with the spermatid areas. Furthermore, the genome sizes agree with the subfamilial taxonomic groupings of these tenebrionids.Key words: Tenebrionidae, genome size, C-banding.

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

Genome ◽  
1997 ◽  
Vol 40 (2) ◽  
pp. 171-175 ◽  
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.

Nuclear DNA content of lobular carcinoma in situ of the breast

Cancer ◽  
1973 ◽  
Vol 31 (6) ◽  
pp. 1553-1560 ◽  
Author(s):  
Arthur S. Ludwig ◽  
Takashi Okagaki ◽  
Ralph M. Richart ◽  
Raffaele Lattes
Keyword(s):  
Dna Content ◽  
Carcinoma In Situ ◽  
Nuclear Dna ◽  
Lobular Carcinoma ◽  
Nuclear Dna Content ◽  
Lobular Carcinoma In Situ

Genome multiplication is a generalised phenomenon in placentomal and interplacentomal trophoblast giant cells in cattle

2004 ◽  
Vol 16 (3) ◽  
pp. 301 ◽  
Author(s):  
Karl Klisch ◽  
Preben D. Thomsen ◽  
Vibeke Dantzer ◽  
Rudolf Leiser
Keyword(s):  
Dna Content ◽  
Nuclear Dna ◽  
In Situ Hybridisation ◽  
Nuclear Dna Content ◽  
Giant Cells ◽  
Crown Rump Length ◽  
Subsequent Determination ◽  
Trophoblast Giant Cells

The frequency of polyploidisation in bovine binucleate trophoblast giant cells (TGC) from placentomes (PL) and the interplacentomal allantochorion (AL) of six male fetuses with a crown–rump length between 3.5 and 103 cm was determined by in situ hybridisation with a chromosome-7-specific probe, using a probe specific for the Y chromosome to distinguish between maternal and fetal nuclei. The results showed that polyploid nuclei were essentially always of fetal origin. The frequency of tetraploid nuclei varied between 3% and 15% in both the placentomal and interplacentomal samples, with mean frequencies of 8.8% and 10.0% respectively. Octoploid nuclei were observed with a mean frequency of 1.1% in the interplacentomal samples, but were absent in samples from placentomes. Subsequent determination of nuclear DNA content by cytophotometric measurement of Feulgen-stained nuclei revealed that the frequency of nuclei with an 8C DNA content was several fold higher (AL 5.4%; PL 7.8%) than the frequency of octoploidy, suggesting that tetraploid TGC cells are arrested in the G2 phase of the cell cycle.

scholarly journals Nuclear DNA Content, Base Composition, and Cytogenetic Characterization of Christia obcordata

2013 ◽  
Vol 138 (3) ◽  
pp. 205-209 ◽  
Author(s):  
Hamidou F. Sakhanokho ◽  
Nurul Islam-Faridi
Keyword(s):  
Ribosomal Rna ◽  
Dna Content ◽  
Nuclear Dna ◽  
Organizer Region ◽  
Nuclear Dna Content ◽  
5S Rdna ◽  
Gene Families ◽  
Root Tip ◽  
Ribosomal Rna Gene ◽  
A Genome

Christia obcordata is an intriguing small-sized house plant with unusual and attractive features such as its striped leaves. Because very little is known about the plant, we conducted an investigation of its genome and chromosomes. The number of chromosomes was determined using a protoplast technique to prepare root tip chromosome spread and was found to be 2n = 2x = 20. Flow cytometry was used to determine nuclear DNA content (1C = 0.65 pg = 634.4 Mb) for C. obcordata and AT/GC composition was shown to be AT% = 62.8% ± 0.0% and GC% = 37.2% ± 0.0%. Finally, fluorescent in situ hybridization was used to locate ribosomal RNA gene families in C. obcordata. Ribosomal RNA gene families, viz. 18S-28S and 5S rDNA, are unique cytomolecular landmarks that provide valuable information about the evolutionary organization of a genome. We have identified one locus each of 18S-28S and 5S rDNA. The 18S-28S rDNA is located in the subterminal position on the secondary constriction region [also known as the nucleolus organizer region (NOR)] and the 5S rDNA is located interstitially close to a centromeric position. The basic information gathered in this study on C. obcordata will be helpful in understanding the genetics of this species.

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