Visualizing DNA domains and sequences by microscopy: a fifty-year history of molecular cytogenetics

Genome ◽  
2003 ◽  
Vol 46 (6) ◽  
pp. 943-946 ◽  
Author(s):  
Hans de Jong
Keyword(s):  
Chromosome Banding ◽  
Molecular Cytogenetics ◽  
Historical Review ◽  
Decisive Role ◽  
Daily Practice ◽  
Short Review ◽  
Chromosome Research ◽  
Specific Chemical ◽  
Detection Systems

This short review presents a historical perspective of chromosome research during the last 50 years. It shows how molecular knowledge and technology of DNA entered cytogenetics step by step making it now daily practice in almost every modern chromosome lab. A crucial milestone in these decades has been the development of in situ protocols by Pardue and Gall, among others, initially only with isotopic labels, and without fluorescence microscopy and sophisticated detection systems. But these very first in situ hybridizations played a decisive role in the discovery of chromosome banding profiles, which were obtained under specific chemical, physical, or enzymatic conditions, thus effecting stainability of specific chromosome regions. In the decades thereafter, numerous technical improvements were achieved leading to complex multi-colour fluorescence in situ hybridization (FISH) protocols for mammals, plants, and insects. Highly improved detection systems of the FISH signals further allowed detection of DNA targets of up to 50 bp, whereas other protocols, which were developed to stretch chromatin fibres to the full length of native DNA, improved spatial resolution of adjacent targets in the light microscope to 1 kb.Key words: historical review, chromosome banding, FISH technology.

Insights into Emydid Turtle Cytogenetics: The European Pond Turtle as a Model Species

2019 ◽  
Vol 157 (3) ◽  
pp. 166-171 ◽  
Author(s):  
Alessio Iannucci ◽  
Marta Svartman ◽  
Massimo Bellavita ◽  
Guido Chelazzi ◽  
Roscoe Stanyon ◽  
...  
Keyword(s):  
Chromosome Banding ◽  
Molecular Cytogenetics ◽  
Comparative Genomic ◽  
Emys Orbicularis ◽  
Rdna Genes ◽  
Telomeric Sequences ◽  
Pond Turtle ◽  
Cytogenetic Data ◽  
Cryptic Sex

Our knowledge of Testudines evolution is limited by the lack of modern cytogenetic data. Compared to other reptiles, there is little information even on chromosome banding, let alone molecular cytogenetic data. Here, we provide detailed information on the karyotype of the European pond turtle Emys orbicularis, a model Emydidae, employing both chromosome banding and molecular cytogenetics. We provide a high-resolution G-banded karyotype and a map of rDNA genes and telomeric sequences using fluorescence in situ hybridization. We test hypotheses of sex-determining mechanisms in Emys by comparative genomic hybridization to determine if Emys has a cryptic sex-specific region. Our results provide valuable data to guide future efforts on genome sequencing and anchoring in Emydidae and for understanding karyotype evolution in Testudines.

scholarly journals Application of the FISH Technique to Visualize Sex Chromosomes in Domestic Cat Spermatozoa

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 2106
Author(s):  
Barbara Kij-Mitka ◽  
Halina Cernohorska ◽  
Svatava Kubickova ◽  
Sylwia Prochowska ◽  
Wojciech Niżański ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Sex Chromosomes ◽  
Chromosomal Abnormalities ◽  
Molecular Cytogenetics ◽  
Molecular Probes ◽  
Domestic Cat ◽  
Fish Technique ◽  
Y Chromosomes

Fluorescence in situ hybridization is a molecular cytogenetics technique that enables the visualization of chromosomes in cells via fluorescently labeled molecular probes specific to selected chromosomes. Despite difficulties in carrying out the FISH technique on sperm, related to the need for proper nuclear chromatin decondensation, this technique has already been used to visualize chromosomes in human, mouse, cattle, swine, horse, and dog spermatozoa. Until now, FISH has not been performed on domestic cat sperm; therefore, the aim of this study was to visualize sex chromosomes in domestic cat sperm. The results showed the presence of X and Y chromosomes in feline spermatozoa. The procedure used for sperm decondensation and fluorescence in situ hybridization was adequate to visualize chromosomes in domestic cat spermatozoa and, in the future, it may be used to determine the degree of chromosomal abnormalities in these gametes.

High Energy Particle Spectrometer for ESA Lagrange mission

2021 ◽  
Author(s):  
Wojtek Hajdas ◽  
Radoslaw Marcinkowski ◽  
Hualin Xiao ◽  
Ronny Kramert
Keyword(s):  
Solar Energetic Particle ◽  
Heavy Ion ◽  
High Energy ◽  
High Energy Particle ◽  
Energy Particle ◽  
Detection Systems ◽  
Parker Spiral ◽  
Final Design ◽  
Radiation Tolerant

<p>The LGR High Energy Particle Spectrometer HEPS for the ESA Lagrange mission belongs to the satellite in-situ instrument suite. The satellite will be placed at the Lagrange point L5 for space weather measurements and real-time observations and alerts. The HEPS instrument with its six detector subsystems will enable the detecting of electrons, protons, and heavy ions at high flux conditions during Solar Energetic Particle Events. The electron and proton detection systems rely on standard telescope techniques covering energy ranges from 100 keV to 15 MeV and 3 MeV to 1 GeV respectively. Two sets of telescopes will be installed facing opposite directions along the Parker spiral. Additional detector with a wide angular range will enable measurements of angular distributions of particles traveling towards the satellite from the Sun. The HEPS heavy-ion telescope HIT represents a new design utilizing a set of scintillators and SiPM light converters. HIT electronics is equipped with a dedicated radiation-tolerant ASIC optimized for low power use and fast signal detections. The first model of HIT was developed and verified for spectroscopic measurements and ion identification. We report on test measurements as well as Monte Carlo simulations of the whole instrument. Results will be discussed and implications on the final design of the instrument provided.</p>

Client-Centred Nutrition Counselling: Do We Know What This Means?

2003 ◽  
Vol 64 (1) ◽  
pp. 12-15 ◽  
Author(s):  
Debbie L. MacLellan ◽  
Shawna Berenbaum
Keyword(s):  
Historical Review ◽  
Daily Practice ◽  
Professional Standards ◽  
Nutrition Counselling ◽  
Counselling Services ◽  
Multiple Meanings

In Canada, professional standards mandate that dietitians should use a client-centred approach to provide nutrition counselling services. Although most dietitians would probably agree that this is an important standard, how this mandate is translated into our daily practice is not always clear. The purpose of this paper is to explore the origins of the “client-centred approach” used in dietetic counselling. A historical review of selected dietetic literature is used to demonstrate the evolution of this term, the multiple meanings associated with it, the remaining ambiguity in dietetic practice today, and the need for further research.

Chromosome Banding in Amphibia. XXXV. Highly Mobile Nucleolus Organizing Regions in Craugastor fitzingeri (Anura, Craugastoridae)

2017 ◽  
Vol 152 (4) ◽  
pp. 180-193 ◽  
Author(s):  
Michael Schmid ◽  
Claus Steinlein ◽  
Wolfgang Feichtinger ◽  
Indrajit Nanda
Keyword(s):  
Chromosome Banding ◽  
Cytogenetic Study ◽  
Variable Number ◽  
28S Rdna ◽  
Fish Analysis ◽  
Intraindividual Variation ◽  
Length Polymorphisms ◽  
Somatic Tissues

A 7-year cytogenetic study on the leaf litter frog Craugastor fitzingeri from Costa Rica and Panama revealed the existence of highly mobile nucleolus organizing regions (NORs) in their genomes. Silver (Ag)-staining of the active NORs demonstrated an exceptional interindividual pattern of NOR distribution at the telomeres of the chromosomes. All individuals examined showed a different and specific NOR location in their karyotypes. Furthermore, intraindividual variation in the NOR sites was found. This observation suggested the existence of mobile NORs in C. fitzingeri. Confirmation of this phenomenon was possible by systematic FISH analysis using an 18S + 28S rDNA probe. The extremely variable number and position of the NORs in C. fitzingeri is best explained by highly mobile NORs that move freely between the telomeres of the chromosomes. These transpositions must occur preferentially in premeiotic, meiotic, or postmeiotic stages, but also at a lower incidence in the somatic tissues of the animals. It is hypothesized that transposable (mobile) elements are closely linked to the NORs or are inserted into the major 18S + 28S rDNA spacers of C. fitzingeri. When such transposable elements spread by transpositions, they can carry with them complete or partial NORs. The present study provides detailed information on various differential chromosome banding techniques, in situ hybridization experiments, chromosomal hypermethylation patterns, determination of the genome size, and analyses of restriction fragment length polymorphisms of the DNA.

Enzymatic detection systems for non-isotopic in situ hybridization using biotinylated cDNA probes

1995 ◽  
Vol 27 (4) ◽  
pp. 280-290 ◽  
Author(s):  
Andreas Trabandt ◽  
Renate E. Gay ◽  
Vikas P. Sukhatme ◽  
Steffen Gay
Keyword(s):  
In Situ Hybridization ◽  
Detection Systems ◽  
Enzymatic Detection

scholarly journals Comparative molecular cytogenetics in Melipona Illiger species (Hymenoptera, Apidae)

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 ◽  
...  
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.

scholarly journals Detection of trisomy 12 by fluorescent in situ hybridization (FISH) in chronic lymphocytic leukemia

2000 ◽  
Vol 23 (3) ◽  
pp. 531-533 ◽  
Author(s):  
Maria de Lourdes L.F. Chauffaille ◽  
Eliana Azevedo Marques ◽  
Jose Salvador Rodrigues de Oliveira ◽  
Maria Madalena Rodrigues ◽  
Maria Stella Figueiredo ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Chronic Lymphocytic Leukemia ◽  
Fluorescent In Situ Hybridization ◽  
Molecular Cytogenetics ◽  
Lymphocytic Leukemia ◽  
Specific Method ◽  
Alpha Satellite ◽  
Trisomy 12 ◽  
Mature Lymphocyte

Chronic lymphocytic leukemia (CLL) presents a varying incidence of karyotypic abnormalities whose detection is complicated by difficulties in obtaining mitosis for analysis in this type of mature lymphocyte disorder. Since the introduction of molecular cytogenetics (FISH = fluorescent in situ hybridization), applying centromeric probes for chromosome 12 has made it possible to detect a higher percentage of trisomy 12 cases. The objective of the present study was to detect trisomy 12 by FISH (alpha satellite probe) in 13 patients with CLL whose karyotypes by G-banding were either normal or inadequate. Using this method trisomy 12 was detected in three patients in a percentage of positive cells varying from 55.5% to 79%, showing that FISH is a sensitive and highly specific method for trisomy detection and should be routinely performed when the karyotype is normal.

scholarly journals Probing Multiscale Disorder in Pyrochlore and Related Complex Oxides in the Transmission Electron Microscope: A Review

2021 ◽  
Vol 9 ◽  
Author(s):  
Jenna L. Wardini ◽  
Hasti Vahidi ◽  
Huiming Guo ◽  
William J. Bowman
Keyword(s):  
Complex Oxides ◽  
Atomic Scale ◽  
High Dimensional ◽  
Detection Systems ◽  
Spatially Resolved ◽  
Chemical Ordering ◽  
Transmission Electron ◽  
The Many ◽  
High Dimensional Datasets

Transmission electron microscopy (TEM), and its counterpart, scanning TEM (STEM), are powerful materials characterization tools capable of probing crystal structure, composition, charge distribution, electronic structure, and bonding down to the atomic scale. Recent (S)TEM instrumentation developments such as electron beam aberration-correction as well as faster and more efficient signal detection systems have given rise to new and more powerful experimental methods, some of which (e.g., 4D-STEM, spectrum-imaging, in situ/operando (S)TEM)) facilitate the capture of high-dimensional datasets that contain spatially-resolved structural, spectroscopic, time- and/or stimulus-dependent information across the sub-angstrom to several micrometer length scale. Thus, through the variety of analysis methods available in the modern (S)TEM and its continual development towards high-dimensional data capture, it is well-suited to the challenge of characterizing isometric mixed-metal oxides such as pyrochlores, fluorites, and other complex oxides that reside on a continuum of chemical and spatial ordering. In this review, we present a suite of imaging and diffraction (S)TEM techniques that are uniquely suited to probe the many types, length-scales, and degrees of disorder in complex oxides, with a focus on disorder common to pyrochlores, fluorites and the expansive library of intermediate structures they may adopt. The application of these techniques to various complex oxides will be reviewed to demonstrate their capabilities and limitations in resolving the continuum of structural and chemical ordering in these systems.

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