Whole mount electron microscopy of meiotic chromosomes and the synaptonemal complex

Chromosoma ◽  
1970 ◽  
Vol 30 (3) ◽  
pp. 269-286 ◽  
Author(s):  
David E. Comings ◽  
Tadashi A. Okada
Keyword(s):  
Electron Microscopy ◽  
Synaptonemal Complex ◽  
Meiotic Chromosomes ◽  
Whole Mount

The application of video-enhanced constrast/differential interference constrast microscopy in conjunction with whole mount electron microscopy to the study of organelle transport

1988 ◽  
Vol 46 ◽  
pp. 66-67
Author(s):  
J. H. Hayden
Keyword(s):  
Electron Microscopy ◽  
Rana Pipiens ◽  
Silver Film ◽  
Immunofluorescence Microscopy ◽  
Organelle Transport ◽  
Linear Element ◽  
Whole Mount ◽  
Carbon Coated ◽  
Linear Elements ◽  
Dic Microscopy

In a previous study, Allen video-enhanced constrast/differential interference constrast (AVEC-DIC) microscopy was used in conjunction with immunofluorescence microscopy to demonstrate that organelles and vesicle move in either direction along linear elements composed of microtubules. However, this study was limited in that the number of microtubules making up a linear element could not be determined. To overcome this limitation, we have used AVEC-DIC microscopy in conjunction with whole mount electron microscopy.Keratocytes from Rana pipiens were grown on glass coverslips as described elsewhere. Gold London Finder grids were Formvar- and carbon coated, and sterilized by exposure to ultraviolet light. It is important to select a Formvar film that gives a grey reflection when it is floated on water. A silver film is too thick and will detract from the image in the light microscope.

Normal Synaptonemal Complex and Abnormal Recombination Nodules in Two Alleles of the Drosophila Meiotic Mutant mei-W68

Genetics ◽  
2003 ◽  
Vol 163 (4) ◽  
pp. 1337-1356 ◽  
Author(s):  
Adelaide T C Carpenter
Keyword(s):  
Electron Microscopy ◽  
Synaptonemal Complex ◽  
High Frequency ◽  
Serial Section ◽  
The Other ◽  
Wild Type ◽  
Recombination Nodules ◽  
Section Electron ◽  
Serial Section Electron Microscopy ◽  
Section Electron Microscopy

Abstract The meiotic phenotypes of two mutant alleles of the mei-W68 gene, 1 and L1, were studied by genetics and by serial-section electron microscopy. Despite no or reduced exchange, both mutant alleles have normal synaptonemal complex. However, neither has any early recombination nodules; instead, both exhibit high numbers of very long (up to 2 μm) structures here named “noodles.” These are hypothesized to be formed by the unchecked extension of identical but much shorter structures ephemerally seen in wild type, which may be precursors of early recombination nodules. Although the mei-W68L1 allele is identical to the mei-W681 allele in both the absence of early recombination nodules and a high frequency of noodles (i.e., it is amorphic for the noodle phene), it is hypomorphic in its effects on exchange and late recombination nodules. The differential effects of this allele on early and late recombination nodules are consistent with the hypothesis that Drosophila females have two separate recombination pathways—one for simple gene conversion, the other for exchange.

scholarly journals Architecture of the Nuclear Periphery of Rat Pachytene Spermatocytes: Distribution of Nuclear Envelope Proteins in Relation to Synaptonemal Complex Attachment Sites

1999 ◽  
Vol 10 (4) ◽  
pp. 1235-1245 ◽  
Author(s):  
Manfred Alsheimer ◽  
Elisabeth von Glasenapp ◽  
Robert Hock ◽  
Ricardo Benavente
Keyword(s):  
Nuclear Envelope ◽  
Synaptonemal Complex ◽  
Meiotic Prophase ◽  
Nuclear Periphery ◽  
Cell Fractionation ◽  
Nuclear Interior ◽  
Meiotic Chromosomes ◽  
Attachment Sites ◽  
Form Part ◽  
Pachytene Spermatocytes

The nucleus of spermatocytes provides during the first meiotic prophase an interesting model for investigating relationships of the nuclear envelope (NE) with components of the nuclear interior. During the pachytene stage, meiotic chromosomes are synapsed via synaptonemal complexes (SCs) and attached through both ends to the nuclear periphery. This association is dynamic because chromosomes move during the process of synapsis and desynapsis that takes place during meiotic prophase. The NE of spermatocytes possesses some peculiarities (e.g., lower stability than in somatic cells, expression of short meiosis-specific lamin isoforms called C2 and B3) that could be critically involved in this process. For better understanding of the association of chromosomes with the nuclear periphery, in the present study we have investigated the distribution of NE proteins in relation to SC attachment sites. A major outcome was the finding that lamin C2 is distributed in the form of discontinuous domains at the NE of spermatocytes and that SC attachment sites are embedded in these domains. Lamin C2 appears to form part of larger structures as suggested by cell fractionation experiments. According to these results, we propose that the C2-containing domains represent local reinforcements of the NE that are involved in the proper attachment of SCs.

scholarly journals The osmium tetroxide-p-phenylenediamine procedure reveals the chromatid cores and kinetochores of meiotic chromosomes by light and electron microscopy.

1996 ◽  
Vol 44 (11) ◽  
pp. 1279-1288 ◽  
Author(s):  
C Antonio ◽  
J M González-García ◽  
J Page ◽  
J A Suja ◽  
J C Stockert ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Reaction Mechanism ◽  
Osmium Tetroxide ◽  
Light And Electron Microscopy ◽  
X Ray ◽  
Meiotic Chromosomes ◽  
Transmission Electron ◽  
Ethanol Acetic Acid ◽  
Electron Imaging ◽  
Z Contrast

We analyzed first-metaphase meiotic chromosomes of the grasshopper Chorthippus jucundus by two different methods, i.e., a silver impregnation technique and the osmium tetroxide-p-phenylenediamine (Os-PPD) procedure. The former was applied on squashed testes previously fixed in ethanol-acetic acid, whereas for Os-PPD the material was not subjected to any previous extraction treatment but was fixed in OsO4, treated with PPD, and embedded in Epon 812. Both techniques revealed chromatid cores and kinetochores regardless of the processing of the material (squashed or sectioned). Unstained Os-PPD sections were analyzed by light microscopy and transmission electron microscopy (TEM). The Os-PPD technique provided a high contrast of chromatid cores and kinetochores in relation to the chromatin, which revealed a low electron density. To determine the Os-PPD reaction mechanism, the PAS procedure, as well as scanning electron microscopy (SEM) backscattering and SEM X-ray microanalysis, was performed on sections. By use of the Os-PPD-PAS procedure, glycol groups formed by oxidation of osmium bound to aromatic substrates were detected in chromatid cores and kinetochores by brightfield and fluorescence microscopy. A high Z contrast was detected in these structures by backscattered electron imaging. SEM X-ray microanalysis showed osmium and phosphorus to be the main elements present on the chromatid cores. Taking into account the known reactivity of OsO4 and the present results, the possible participation of nucleic acids as well as proteins in the Os-PPD reaction mechanism and in the composition of chromatid cores and kinetochores is discussed.

Sign in / Sign up

Export Citation Format

Share Document