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Metaphase Chromosomes (metaphase + chromosome)

Distribution by Scientific Domains

Life Sciences	57%
Medical Sciences	42%

Selected Abstracts

A comparative proteome analysis of human metaphase chromosomes isolated from two different cell lines reveals a set of conserved chromosome-associated proteins

GENES TO CELLS, Issue 3 2007
Hideaki Takata
A comparative proteome analysis of human metaphase chromosomes between a typical epithelial-like cell, HeLa S3, and a lymphoma-type cell, BALL-1, was performed. One-dimensional (1-D) SDS-PAGE and radical-free and highly reducing two-dimensional electrophoresis (RFHR 2-DE) detected more than 200 proteins from chromosomes isolated from HeLa S3 cells, among which 189 proteins were identified by mass spectrometry (MS). Consistent with our recent four-layer structural model of a metaphase chromosome, all the identified proteins were grouped into four distinct levels of abundance. Both HeLa S3 and BALL-1 chromosomes contained specific sets of abundant chromosome structural and peripheral proteins in addition to less abundant chromosome coating proteins (CCPs). Furthermore, titin array analysis and a proteome analysis of the ultra-high molecular mass region indicated an absence of titin with their molecular weight (MW) more than 1000 kDa. Consequently, the present proteome analyses together with previous information on chromosome proteins provide the comprehensive list of proteins essential for the metaphase chromosome architecture. [source]

Localization of single-copy T-DNA insertion in transgenic shallots (Allium cepa) by using ultra-sensitive FISH with tyramide signal amplification

THE PLANT JOURNAL, Issue 6 2001
Ludmila I. Khrustaleva
Summary The sensitivity of fluorescence in situ hybridization (FISH) for mapping plant chromosomes of single-copy DNA sequences is limited. We have adapted for plant cytogenetics a new signal-amplification method termed tyramide-FISH (Tyr-FISH). Until present this technique has only been applied to human chromosomes. The method is based on enzymatic deposition of fluorochrome-conjugated tyramide. With Tyr-FISH it was possible to detect target T-DNA sequences on plant metaphase chromosomes as small as 710 bp without using a cooled CCD camera. Short detection time and high sensitivity, in combination with a low background, make the Tyr-FISH method very suitable for routine application in plant cytogenetic research. With Tyr-FISH we analysed the position of T-DNA inserts in transgenic shallots. We found that the inserts were preferentially located in the distal region of metaphase chromosomes. Sequential fluorescence in situ hybridization with a 375 bp satellite sequence suggested that a specific T-DNA insert was located within the satellite sequence hybridization region on a metaphase chromosome. Analysis of less-condensed prophase and interphase chromosomes revealed that the T-DNA was integrated outside the satellite DNA-hybridization region in a more proximal euchromatin region. [source]

A comparative proteome analysis of human metaphase chromosomes isolated from two different cell lines reveals a set of conserved chromosome-associated proteins

The common fragile site FRA16D and its associated gene WWOX are highly conserved in the mouse at Fra8E1

GENES, CHROMOSOMES AND CANCER, Issue 2 2002
Kurt A. Krummel
Recently, several common fragile sites (CFSs) have been cloned and characterized, including the two most frequently observed in the human population, FRA3B and FRA16D. In addition to their high frequency of breakage, FRA3B and FRA16D colocalize with genes crossing large regions of breakage. At FRA3B, the fragile histidine triad (FHIT) gene spans more than 1 Mb, and at FRA16D, the WWOX gene spans more than 750 kb. It has also been shown that in Mus musculus, a CFS Fra14A2 and the mouse Fhit gene are conserved in the orthologous region of the genome. In this study, we positioned the ortholog to WWOX (Wox1) at chromosome band 8E1 in the mouse genome. To determine whether, like Fra14A2 and Fhit, Fra8E1 and Wox1 colocalized in the mouse, we prepared bacterial and yeast artificial chromosome probes, and we hybridized them to aphidicolin-treated mouse metaphase chromosomes. Our data demonstrate that Wox1 colocalizes with Fra8E1. Furthermore, the sequence from this region, including introns, is highly conserved over at least a 100-kb region. This evolutionary conservation suggests that the two most active CFSs share many features, and that CFSs and their associated genes may be necessary for cell survival. © 2002 Wiley-Liss, Inc. [source]

Detection of unidentified chromosome abnormalities in human neuroblastoma by spectral karyotyping (SKY)

GENES, CHROMOSOMES AND CANCER, Issue 3 2001
Ninette Cohen
Spectral karyotyping (SKY) is a novel technique based on the simultaneous hybridization of 24 fluorescently labeled chromosome painting probes. It provides a valuable addition to the investigation of many tumors that can be difficult to define by conventional banding techniques. One such tumor is neuroblastoma, which is often characterized by poor chromosome morphology and complex karyotypes. Ten primary neuroblastoma tumor samples initially analyzed by G-banding were analyzed by SKY. In 8/10 tumors, we were able to obtain additional cytogenetic information. This included the identification of complex rearrangements and material of previously unknown origin. Structurally rearranged chromosomes can be identified even in highly condensed metaphase chromosomes. Following the SKY results, the G-banding findings were reevaluated, and the combination of the two techniques resulted in a more accurate karyotype. This combination allows identification not only of material gained and lost, but also of breakpoints and chromosomal associations. The use of SKY is therefore a powerful tool in the genetic characterization of neuroblastoma and can contribute to a better understanding of the molecular events associated with this tumor. © 2001 Wiley-Liss, Inc. [source]

Fluorescent in situ hybridization mapping of the epidermal growth factor receptor gene in donkey

JOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 3 2007
M. Bugno
Summary The physical localization of the epidermal growth factor receptor (EGFR) gene was performed on donkey chromosomes. Bacterial artificial chromosome DNA containing the equine EGFR gene was used to map this gene by fluorescent in situ hybridization on donkey metaphase chromosomes. The gene was mapped on donkey 1q21.1 region. [source]

Molecular genetic characterization of Robertsonian translocations in cattle

JOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 6 2001
H. Joerg
The chromosome fusion of acrocentric chromosomes, known as Robertsonian translocations, are the most common chromosome rearrangement in Bovidae. Cytogenetic studies revealed differences between the centromeres of Robertsonian translocations: the rob(1; 29) is called monocentric, whereas rob(14; 20) is a dicentric chromosome. To analyse the type of fusion, satellite sequences were hybridised to metaphase chromosomes of carriers of rob(1; 29) from different breeds and rob(14; 20) from the Simmental breed. A repeat element of the bovine 1.715 satellite was located in the centromeric regions of all 29 bovine acrocentric chromosomes. No signals were observed on either the X-,Y- or the rob(1; 29) chromosomes. In contrast, all rob(14; 20) chromosomes gave a distinct hybridisation signal. Microsatellite markers in the linkage group, originating from the fusion, revealed a characteristic allele combination for rob(1; 29) in all carriers and were able to confirm the screening of metaphases of 220 daughters of a heterozygote carrier of the rob(1; 29). The results indicate that rob(1; 29) lost parts of both centromeres and that the 1.715 satellite DNA is not necessary for the functioning of the centromere. Furthermore, rob(1; 29) appears to derive from the same mutation and is transmitted according to Mendelian law. Molekulargenetische Charakterisierung von Robertson'schen Translokationen beim Rind Die Fusion von akrozentrischen Chromosomen, bekannt als Robertson'sche Translokationen, sind die häufigsten Chromosomenveränderungen in der Rindergattung. Zytogenetische Studien zeigten Unterschiede in den Zentromeren von Robertson'schen Translokationen auf. Das Rob(1; 29) Chromosom wird als ein monozentrisches und das Rob(14/20) als ein dizentrisches Chromosom bezeichnet. Um die Fusionsarten zu analysieren, wurden Satellitensequenzen auf Metaphasenchromosomen von Trägern der Rob(1; 29) aus verschiedenen Rassen und von Trägern der Rob(14; 20) aus der Rasse der Simmentaler hybridisiert. Eine Sequenzwiederholung aus dem Rindersatelliten 1.715 wurde in den Zentromerregionen aller 29 akrozentrischer Rinderchromosomen nachgewiesen. Auf dem X, dem Y wie auch auf dem Rob(1; 29) Chromosom konnten jedoch keine Signale beobachtet werden, während alle Rob(14; 20) Chromosomen ein starkes Hybridisierungssignal aufwiesen. Die Mikrosatelliten in der Kopplungsgruppe, welche durch die Fusion entstanden ist, zeigten eine charakteristische Allelkombination für das Rob(1; 29) Chromsom und konnten Untersuchungen an den Metaphasen von 220 Töchtern eines heterozygoten Trägers bestätigen. Die Ergebnisse weisen darauf hin, dass Rob(1; 29) Chromosomen einen Teil beider Zentromere verloren haben und dass die 1.715 Satelliten DNA für ein funktionierendes Chromosom nicht notwendig ist. Die Rob(1; 29) Chromosomen scheinen eine identische Abstammung aufzuweisen und werden nach den Mendel'schen Regeln vererbt. [source]

First Evidence of Genetic Imbalances in Angiofibromas

THE LARYNGOSCOPE, Issue 2 2002
Bernhard Schick MD
Abstract Objective/Hypothesis Angiofibromas are clinically well characterized by their origin at the posterior lateral nasal wall close to the sphenopalatine foramen, their occurrence in male adolescent patients, and the histological findings of a benign fibrovascular neoplasm with irregular, endothelium-lined vascular spaces in a fibrous stroma. However, their etiology and genetic causes remain unknown. The present study addresses genetic imbalances in angiofibromas. Study Design The present pilot study compared genomic hybridization in three angiofibromas to search for chromosomal abnormalities in this rare tumor. Methods Fluorescence-marked normal DNA and angiofibroma DNA were compared using genomic hybridization screening to detect chromosomal abnormalities. Their binding ratio to metaphase chromosomes were analyzed by special digital image analysis. Results Chromosomal gains and losses showing a high level of agreement were detected in all three angiofibromas. Specifically, DNA gains were observed on chromosomes 3q, 4q, 5q, 6q, 7q, 8q, 12p, 12q, 13q, 14q, 18q, 21q, and X, and DNA losses were screened on chromosomes 17, 19p, 22q, and Y. Finding chromosomal abnormalities at the sex chromosomes X and Y of this rare tumor is remarkable. Concurrent chromosomal gain on 8q12q22 was noted in all three tumor specimens. Conclusions Comparative genomic hybridization is suitable for screening angiofibromas on a genetic level. The results on these screens indicate that further genetic investigations of this rare benign tumor may provide more details about the tumor's genetic abnormalities and perhaps clarify the etiology of angiofibromas. [source]

Localization of single-copy T-DNA insertion in transgenic shallots (Allium cepa) by using ultra-sensitive FISH with tyramide signal amplification

FISH mapping and sequence analysis of 87 porcine BAC clones

ANIMAL GENETICS, Issue 1 2004
R. Anistoroaei
Summary Ninety-one bacterial artificial chromosomes (BAC) clones, selected effectively at random from our library, were used as probes for fluorescence in situ hybridization. Of these, 87 clones gave a specific signal in one, two or three different pair(s) of swine metaphase chromosomes. The ends of 35 BAC clones were sequenced in order to obtain information for comparative mapping. Fifteen of them gave useful comparative mapping information. [source]

Calcium phosphate transfection generates mammalian recombinant cell lines with higher specific productivity than polyfection

BIOTECHNOLOGY & BIOENGINEERING, Issue 5 2008
Sebastien Chenuet
Abstract Transfection with polyethylenimine (PEI) was evaluated as a method for the generation of recombinant Chinese hamster ovary (CHO DG44) cell lines by direct comparison with calcium phosphate-DNA coprecipitation (CaPO4) using both green fluorescent protein (GFP) and a monoclonal antibody as reporter proteins. Following transfection with a GFP expression vector, the proportion of GFP-positive cells as determined by flow cytometry was fourfold higher for the PEI transfection as compared to the CaPO4 transfection. However, the mean level of transient GFP expression for the cells with the highest level of fluorescence was twofold greater for the CaPO4 transfection. Fluorescence in situ hybridization on metaphase chromosomes from pools of cells grown under selective pressure demonstrated that plasmid integration always occurred at a single site regardless of the transfection method. Importantly, the copy number of integrated plasmids was measurably higher in cells transfected with CaPO4. The efficiency of recombinant cell line recovery under selective pressure was fivefold higher following PEI transfection, but the average specific productivity of a recombinant antibody was about twofold higher for the CaPO4-derived cell lines. Nevertheless, no difference between the two transfection methods was observed in terms of the stability of protein production. These results demonstrated the feasibility of generating recombinant CHO-derived cell lines by PEI transfection. However, this method appeared inferior to CaPO4 transfection with regard to the specific productivity of the recovered cell lines. Biotechnol. Bioeng. © 2008 Wiley Periodicals, Inc. [source]

Comparative genomic hybridization (CGH)-arrays pave the way for identification of novel cancer-related genes

CANCER SCIENCE, Issue 7 2004
Johji Inazawa
Comparative genomic hybridization (CGH) has already made a significant impact on cancer Cytogenetics. However, CGH to metaphase chromosomes can provide only limited resolution at the 5,10 Mb level. To circumvent this limitation, array-based CGH has been devised. Since spotted DMAs in a CGH-array contain sequence information directly connected with the genome database, we can easily note particular biological aspects of genes that lie within regions involved in copy-number aberrations. High-density, sub-megabase arrays can reveal nonrandom chromosome copy-number aberrations responsible for neoplastic transformation that have been masked under complex karyotypes in epithelial solid tumors. High-density CGH-array therefore paves the way for identification of disease-related genetic aberrations that have not yet been detected by existing technologies, and array-based CGH technology should soon be practical for diagnosis of cancer or genetic diseases in the clinical setting. [source]

A new genomic duplication syndrome complementary to the velocardiofacial (22q11 deletion) syndrome

CLINICAL GENETICS, Issue 5 2004
SJ Hassed
Fluorescence in situ hybridization (FISH) analysis can reveal undetected chromosomal rearrangements. We report a patient with cleft palate, hydronephrosis, and minor dysmorphic features, including low-set posteriorly rotated ears, down-slanting palpebral fissures, mandibular micrognathia, and brachymesophalangia. Routine chromosome analysis identified no abnormality of chromosome 22; FISH analysis with the TUPLE1 probe disclosed an interstitial duplication of 22q11.2. FISH analysis did not reveal the duplication on the initial testing of metaphase chromosomes, although, on review, the area was brighter on one chromosome in each metaphase spread. FISH analysis of interphase cells showed three TUPLE1-probe sites with two chromosome-specific identification probes in each cell. Family history showed two older full siblings, a brother with behavior problems, oppositional defiant disorder, and learning problems and a sister with hydronephrosis and mild delays. The father and both siblings had similar facial features, and all three had the same interstitial duplication of the TUPLE1 probe. This family illustrates the novel complementary duplication syndrome of the velocardiofacial syndrome, which adds it to the expanding list of genomic deletion/duplication syndromes. The laboratory results further show the utility and need for careful analysis of interphase cells even in samples where good quality metaphases are available. [source]