Identical megabase transgenes on mouse chromosomes 3 and 4 do not promote ectopic pairing or synapsis at meiosis

Genome ◽  
1997 ◽  
Vol 40 (5) ◽  
pp. 770-773 ◽  
Author(s):  
P. B. Moens ◽  
J. A. M. Heddle ◽  
B. Spyropoulos ◽  
H. H. Q. Heng
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Synaptonemal Complex ◽  
Meiotic Prophase ◽  
Nuclear Volume ◽  
Dna Interactions ◽  
Synaptonemal Complexes ◽  
Meiotic Chromosomes ◽  
Ectopic Pairing

To investigate ectopic interactions at the chromatin level, we examined the meiotic organization of 1–2 mb phage λ transgenes on mouse chromosomes 3 and 4 by fluorescence in situ hybridization in combination with immunocytology of meiotic chromosomes. At early meiotic prophase, the transgenes are sufficiently dispersed in the nuclear volume to permit potential DNA–DNA interactions, but no synaptonemal complexes form between the sites of transgenes residing on different chromosomes. At later stages, when the chromatin is more condensed, the transgenes on different chromosomes are not preferentially associated as they are when they are on the same chromosome. At diplotene and metaphase I, no formations were observed that could be interpreted as reciprocal crossovers or chiasmata between the transgenes located on chromosomes 3 and 4. It appears that in normal fertile mice, a 1- to 2-mb homology is insufficient to initiate synapsis between nonhomologs, and it is concluded that homology is assessed within the broader context of the chromosome to initiate synapsis at meiotic prophase.Key words: transgenes, ectopic pairing, meiosis, synaptonemal complex, immunocytology, FISH.

Spectral karyotyping (SKY) of mouse meiotic chromosomes

Genome ◽  
2001 ◽  
Vol 44 (2) ◽  
pp. 293-298 ◽  
Author(s):  
Henry HQ Heng ◽  
Guo Liu ◽  
Wei Lu ◽  
Steve Bremer ◽  
Christine J Ye ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Synaptonemal Complex ◽  
Meiotic Prophase ◽  
Spectral Karyotyping ◽  
Mitotic Chromosomes ◽  
Meiotic Chromosomes ◽  
Y Chromosomes ◽  
Behavioural Characteristics ◽  
Co Detection

The spectral karyotyping procedure of in situ hybridization with chromosome-specific probes assigns a unique colour code to each of the 21 mouse mitotic chromosomes. We have adapted this procedure to meiotic prophase chromosomes, and the results show that each of the pachytene or metaphase I bivalents can be identified. This technique has the potential to recognize synaptic anomalies and chromosome-specific structural and behavioural characteristics. We confirm these potentials by the recognition of the heterologous synapsis of the X and Y chromosomes and by the variances of synaptonemal complex lengths for each of the colour-coded bivalents in eight prophase nuclei.Key words: SKY, meiosis, synaptonemal complex, multicolour, chromosome painting, spectral karyotyping, protein-SKY co-detection.

scholarly journals Lateral Elements Inside Synaptonemal Complex-Like Polycomplexes in ndt80 Mutants of Yeast Bind DNA

Genetics ◽  
2003 ◽  
Vol 163 (2) ◽  
pp. 539-544 ◽  
Author(s):  
Hasanuzzaman Bhuiyan ◽  
Gunilla Dahlfors ◽  
Karin Schmekel
Keyword(s):  
In Situ Hybridization ◽  
Electron Microscope ◽  
Synaptonemal Complex ◽  
Immunoelectron Microscopy ◽  
Meiotic Prophase ◽  
Lateral Element ◽  
Homologous Chromosomes ◽  
Meiotic Prophase I ◽  
Dna Antibodies

Abstract The synaptonemal complex (SC) keeps the synapsed homologous chromosomes together during pachytene in meiotic prophase I. Structures that resemble stacks of SCs, polycomplexes, are sometimes found before or after pachytene. We have investigated ndt80 mutants of yeast, which arrest in pachytene. SCs appear normal in spread chromosome preparations, but are only occasionally found in intact nuclei examined in the electron microscope. Instead, large polycomplexes occur in almost every ndt80 mutant nucleus. Immunoelectron microscopy using DNA antibodies show strong preferential labeling to the lateral element parts of the polycomplexes. In situ hybridization using chromosome-specific probes confirms that the chromosomes in ndt80 mutants are paired and attached to the SCs. Our results suggest that polycomplexes can be involved in binding of chromosomes and possibly also in synapsis.

In situ localization of two repetitive DNA sequences to surface-spread pachytene chromosomes of rye

Genome ◽  
1992 ◽  
Vol 35 (4) ◽  
pp. 551-559 ◽  
Author(s):  
S. M. Albini ◽  
T. Schwarzacher
Keyword(s):  
In Situ Hybridization ◽  
Synaptonemal Complex ◽  
Dna Sequences ◽  
Meiotic Prophase ◽  
Hybridization Signal ◽  
Metaphase Chromosomes ◽  
Somatic Metaphase ◽  
Rdna Signal ◽  
Surface Spread

Surface-spread pollen mother cells at meiotic prophase from Secale cereale (rye) were used for fluorescent DNA:DNA in situ localization of two tandemly repeated DNA sequences: pTa71, a wheat rDNA clone, and pSc119.2, a cloned 120-bp repeat from rye heterochromatin. The fluorescent hybridization signal, consisting of many yellow-green dots, was closely associated with the bivalent axes, corresponding to the synaptonemal complex, and located in the surrounding chromatin. The rDNA signal was associated with one bivalent, the smallest of the seven, at a distance about 13% of the bivalent length from the telomere. This corresponded to the position of the nucleolar organizing region of silver-stained synaptonemal complexes analyzed under the electron microscope and published data for somatic metaphase chromosomes. The relative length of the axis covered with the rDNA signal is less than expected from somatic metaphases, but it corresponds more closely to the proportion of the sequences in the genome. The hybridization signal with the 120-bp repeat was located mainly at the telomeric regions of several bivalents that showed thickenings of the axis after DAPI staining, probably corresponding to somatic C-bands. These major and some minor intercalary sites agree with the distribution of the 120-bp repeat in somatic metaphase. Fluorescent in situ hybridization to plant surface-spread pachytene chromosomes, which can be obtained in large numbers, has great potential for studying meiotic prophase, high-resolution mapping of DNA sequences, and investigating the relationship of DNA sequences to the synaptonemal complex.Key words: in situ hybridization, cereals, pachytene, meiosis, synaptonemal complex, physical mapping.

scholarly journals Localization of Single- and Low-Copy Sequences on Tomato Synaptonemal Complex Spreads Using Fluorescence in Situ Hybridization (FISH)

Genetics ◽  
1999 ◽  
Vol 152 (1) ◽  
pp. 427-439 ◽  
Author(s):  
Daniel G Peterson ◽  
Nora L V Lapitan ◽  
Stephen M Stack
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Synaptonemal Complex ◽  
Dna Sequences ◽  
Single Copy ◽  
Differential Staining ◽  
Rflp Markers ◽  
Metaphase Chromosomes ◽  
Fish Mapping

Abstract Fluorescence in situ hybridization (FISH) is a powerful means by which single- and low-copy DNA sequences can be localized on chromosomes. Compared to the mitotic metaphase chromosomes that are normally used in FISH, synaptonemal complex (SC) spreads (hypotonically spread pachytene chromosomes) have several advantages. SC spreads (1) are comparatively free of debris that can interfere with probe penetration, (2) have relatively decondensed chromatin that is highly accessible to probes, and (3) are about ten times longer than their metaphase counterparts, which permits FISH mapping at higher resolution. To investigate the use of plant SC spreads as substrates for single-copy FISH, we probed spreads of tomato SCs with two single-copy sequences and one low-copy sequence (ca. 14 kb each) that are associated with restriction fragment length polymorphism (RFLP) markers on SC 11. Individual SCs were identified on the basis of relative length, arm ratio, and differential staining patterns after combined propidium iodide (PI) and 4′,6-diamidino-2-phenylindole (DAPI) staining. In this first report of single-copy FISH to SC spreads, the probe sequences were unambiguously mapped on the long arm of tomato SC 11. Coupled with data from earlier studies, we determined the distance in micrometers, the number of base pairs, and the rates of crossing over between these three FISH markers. We also observed that the order of two of the FISH markers is reversed in relation to their order on the molecular linkage map. SC-FISH mapping permits superimposition of markers from molecular linkage maps directly on pachytene chromosomes and thereby contributes to our understanding of the relationship between chromosome structure, gene activity, and recombination.

Labeling Meiotic Chromosomes in Maize with Fluorescence In Situ Hybridization

2013 ◽  
pp. 35-43
Author(s):  
Zhi Gao ◽  
Fangpu Han ◽  
Tatiana V. Danilova ◽  
Jonathan C. Lamb ◽  
Patrice S. Albert ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Meiotic Chromosomes
Sign in / Sign up

Export Citation Format

Share Document