MEIOSIN directs initiation of meiosis and subsequent meiotic prophase program during spermatogenesis

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.

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DNA AND THE FINE STRUCTURE OF SYNAPTIC CHROMOSOMES IN THE DOMESTIC ROOSTER (GALLUS DOMESTICUS)

The Journal of Cell Biology ◽

10.1083/jcb.23.1.63 ◽

1964 ◽

Vol 23 (1) ◽

pp. 63-78 ◽

Cited By ~ 47

Author(s):

James R. Coleman ◽

Montrose J. Moses

Keyword(s):

Electron Microscopy ◽

Heavy Metal ◽

Fine Structure ◽

Electron Microscope ◽

Meiotic Prophase ◽

Gallus Domesticus ◽

Feulgen Staining ◽

Synaptinemal Complex ◽

Relationship Of ◽

The Relationship

The indium trichloride method of Watson and Aldridge (38) for staining nucleic acids for electron microscopy was employed to study the relationship of DNA to the structure of the synaptinemal complex in meiotic prophase chromosomes of the domestic rooster. The selectivity of the method was demonstrated in untreated and DNase-digested testis material by comparing the distribution of indium staining in the electron microscope to Feulgen staining and ultraviolet absorption in thicker sections seen with the light microscope. Following staining by indium, DNA was found mainly in the microfibril component of the synaptinemal complex. When DNA was known to have been removed from aldehyde-fixed material by digestion with DNase, indium stainability was also lost. However, staining of the digested material with non-selective heavy metal techniques demonstrated the presence of material other than DNA in the microfibrils and showed that little alteration in appearance of the chromosome resulted from DNA removal. The two dense lateral axial elements of the synaptinemal complex, but not the central one to any extent, also contained DNA, together with non-DNA material.

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The CSN/COP9 Signalosome Regulates Synaptonemal Complex Assembly during Meiotic Prophase I of Caenorhabditis elegans

PLoS Genetics ◽

10.1371/journal.pgen.1004757 ◽

2014 ◽

Vol 10 (11) ◽

pp. e1004757 ◽

Cited By ~ 16

Author(s):

Heather Brockway ◽

Nathan Balukoff ◽

Martha Dean ◽

Benjamin Alleva ◽

Sarit Smolikove

Keyword(s):

Caenorhabditis Elegans ◽

Synaptonemal Complex ◽

Meiotic Prophase ◽

Cop9 Signalosome ◽

Complex Assembly ◽

Prophase I ◽

Meiotic Prophase I

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Cytological aspects of gametogenesis in two rhigonematid (Nematoda) parasites of Anadenobolus politus (Porat) (Rhinocricidae; Diplopoda) from Guadeloupe

Canadian Journal of Zoology ◽

10.1139/z84-031 ◽

1984 ◽

Vol 62 (2) ◽

pp. 190-192 ◽

Cited By ~ 1

Author(s):

Martin L. Adamson ◽

Daniel Van Waerebeke

Keyword(s):

X Chromosome ◽

Meiotic Prophase ◽

Meiotic Metaphase ◽

Autosomal Pair

Certain cytological aspects of gametogenesis are examined in two species of rhigonematid nematodes parasitizing the posterior gut of Anadenobolus politus (Rhinocricidae; Diplopoda) in Guadeloupe. In both species, sex is determined by an XX/XO mechanism; this is taken as an indication of the phylogenetic distinctness of rhigonematids from the order Oxyurida which recent studies show to be haplodiploid. In Ichthyocephalus anadenoboli. males had 9 and females had 10 chromosomes; in Heth mauriesi, males had 15 and females had 16 chromosomes. In both species, the X chromosome and one autosomal pair were positively heteropyenotic (i.e., they condensed before and stained more intensely than the rest of the chromosomes) during meiotic prophase in males; in H. mauriesi, these chromosomes were negatively heteropyenotic during meiotic metaphase in males. In females of both species, all chromosomes stained similarly.

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Oogenesis: Chromatin and microtubule dynamics during meiotic prophase

Molecular Reproduction and Development ◽

10.1002/mrd.1080250411 ◽

1990 ◽

Vol 25 (4) ◽

pp. 374-383 ◽

Cited By ~ 216

Author(s):

Britta A. Mattson ◽

David F. Albertini

Keyword(s):

Meiotic Prophase ◽

Microtubule Dynamics

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Automated and customizable quantitative image analysis of whole Caenorhabditis elegans germlines

Genetics ◽

10.1093/genetics/iyab010 ◽

2021 ◽

Author(s):

Erik Toraason ◽

Victoria L Adler ◽

Nicole A Kurhanewicz ◽

Acadia DiNardo ◽

Adam M Saunders ◽

...

Keyword(s):

Image Analysis ◽

Caenorhabditis Elegans ◽

Germ Cell ◽

Meiotic Prophase ◽

Quantitative Image Analysis ◽

Dna Breaks ◽

C Elegans ◽

Quantitative Image ◽

Cytological Features ◽

Single Nucleus

Abstract Arranged in a spatial-temporal gradient for germ cell development, the adult germline of Caenorhabditis elegans is an excellent system for understanding the generation, differentiation, function, and maintenance of germ cells. Imaging whole C. elegans germlines along the distal-proximal axis enables powerful cytological analyses of germ cell nuclei as they progress from the pre-meiotic tip through all the stages of meiotic prophase I. To enable high-content image analysis of whole C. elegans gonads, we developed a custom algorithm and pipelines to function with image processing software that enables: (1) quantification of cytological features at single nucleus resolution from immunofluorescence images; and (2) assessment of these individual nuclei based on their position within the germline. We show the capability of our quantitative image analysis approach by analyzing multiple cytological features of meiotic nuclei in whole C. elegans germlines. First, we quantify double-strand DNA breaks (DSBs) per nucleus by analyzing DNA-associated foci of the recombinase RAD-51 at single-nucleus resolution in the context of whole germline progression. Second, we quantify the DSBs that are licensed for crossover repair by analyzing foci of MSH-5 and COSA-1 when they associate with the synaptonemal complex during meiotic prophase progression. Finally, we quantify P-granule composition across the whole germline by analyzing the colocalization of PGL-1 and ZNFX-1 foci. Our image analysis pipeline is an adaptable and useful method for researchers spanning multiple fields using the C. elegans germline as a model system.

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