Comparative study of sperm chromatin condensation in the excurrent ducts of the laboratory mouse Mus musculus and spinifex hopping mouse Notomys alexis

2005 ◽  
Vol 17 (6) ◽  
pp. 611 ◽  
Author(s):  
M. Bauer ◽  
C. Leigh ◽  
E. Peirce ◽  
W. G. Breed
Keyword(s):  
Vas Deferens ◽  
Chromatin Condensation ◽  
Laboratory Mouse ◽  
Sodium Dodecyl ◽  
Sperm Maturation ◽  
Sperm Chromatin ◽  
Rapid Progression ◽  
Mouse Sperm ◽  
Sperm Nuclei ◽  
Cauda Epididymidis

In most mammals, post-testicular sperm maturation is completed in the caput and corpus epididymides, with storage occurring in the cauda epididymides. However, in the spinifex hopping mouse, Notomys alexis, epididymal sperm transit is rapid and some sperm storage occurs in the distal region of the vas deferens. The aim of the present study was to determine whether the rapid progression of sperm into the vas deferens in the hopping mouse results in late sperm maturation. To determine this, sperm nuclei from the epididymides and vasa deferentia of laboratory and hopping mice were compared for: (1) thiol content after staining with monobromobimane (mBBr); (2) chromatin resistance to acid denaturation following incubation with acetic alcohol and staining with acridine orange; and (3) chromatin resistance to in vitro decondensation after incubation with 1% sodium dodecyl sulfate (SDS). It was found that, whereas laboratory mouse sperm completed chromatin condensation by the time they reached the cauda epididymidis, hopping mouse sperm nuclei from the vas deferens showed significantly less mBBr fluorescence and a greater proportion of sperm were resistant to decondensation with SDS than those in the cauda epididymidis. Therefore, the results of the present study indicate that, unlike in the laboratory mouse, hopping mouse chromatin condensation of spermatozoa continues in the vas deferens and this may be due, at least in part, to rapid epididymal transit.

scholarly journals Meiotic DNA synthesis during mouse spermatogenesis.

1975 ◽  
Vol 64 (1) ◽  
pp. 211-222 ◽  
Author(s):  
M L Meistrich ◽  
B O Reid ◽  
W J Barcellona
Keyword(s):  
Dna Synthesis ◽  
Nuclear Dna ◽  
Sodium Dodecyl ◽  
Phenol Extraction ◽  
Sperm Dna ◽  
Sperm Nuclei ◽  
Cauda Epididymidis ◽  
Contamination Levels ◽  
Triton X ◽  
Mechanical Shearing

The incorporation of radioactivity into various cells in the sequence of spermatogenesis was measured by preparing highly purified spermatozoan nuclei from the cauda epididymidis of mice at daily intervals after injection of (3H)thymidine. The stages of differentiation of these sperm at the time of thymidine administration were calculated from the kinetics of spermatogenesis. The procedure for purification of sperm nuclei included sonication, mechanical shearing, and treatment with trypsin, DNase, Triton X-100, 2M NaC1, and sodium dodecyl sulfate. DNA was isolated from these nuclei by treatment with dithiothreitol and pronase, followed by phenol extraction and ethanol precipitation. The levels of radioactivity in the epididymal sperm head preparations were low (less than 13 dpm/mouse) for 27 days after injection, and then rose dramatically to over 4 times 104 dpm/mouse. Further experiments demonstrated that the 11 dpm of 3H radioactivity contained in sperm heads at 21 or 26 days after injection of (3H)TdR was significantly above background and contamination levels from other cells or other sources. Most of the radioactivity was in the sperm DNA and represented incorporation of tritium from (3H)TdR into the nuclear DNA of meiotic cells at 0.002 percent of the rate of incorporation into S-phase cells. Little, if any, (3H)TdR was incorporation into the DNA of spermatids. The levels of DNA synthesis during the meiotic prophase in the mouse appear to be much lower than those reported for other organisms.

Effects of pivalic acid and sodium pivalate on L-carnitine concentrations in the cauda epididymidis and on male fertility in the hamster

1997 ◽  
Vol 9 (4) ◽  
pp. 427 ◽  
Author(s):  
L. M. Lewin ◽  
S. Fournier-Delpech ◽  
R. Weissenberg ◽  
R. Golan ◽  
T. Cooper ◽  
...  
Keyword(s):  
Sodium Salt ◽  
Chromatin Condensation ◽  
Pivalic Acid ◽  
Fertility Treatment ◽  
Sperm Chromatin ◽  
High Concentration ◽  
Cell Stage ◽  
Cauda Epididymidis ◽  
Male Golden Hamsters ◽  
Carnitine Concentration

In this study, administration of pivalic acid or its sodium salt was found to decrease the L-carnitine concentration in the epididymal lumen of the hamster; it also tested whether this decrease affected sperm cell motility, chromatin structure, or fertilizing capacity. Provision of pivalic acid or its sodium salt (20 mM or 40 mM) in the drinking water of mature male golden hamsters for 30 days reduced (by 72%, 75%, and 83% in three experiments) the L-carnitine concentration of the cauda epididymidis but did not inhibit sperm chromatin condensation, as assessed by flow cytometry. The treatments did not alter the location of motile sperm in the epididymidis nor did they appreciably affect the motility of sperm obtained from the distal cauda epididymidis. The numbers and percentage of ova that reached the 2-cell stage 36–40 h after uterine insemination with spermatozoa from control and treated hamsters served as a measure of sperm fertility. Treatment with pivalic acid or sodium pivalate did not render male hamsters infertile although it appeared to reduce the fertilizing ability of their spermatozoa. These results suggest that the high concentration of L-carnitine present in the lumen of the cauda epididymidis is not required for maturation of sperm chromatin or development of sperm motility.

scholarly journals Studies on sperm storage in the vas deferens of the spinifex hopping mouse (Notomys alexis)

Reproduction ◽  
2003 ◽  
pp. 233-240 ◽  
Author(s):  
EJ Peirce ◽  
HD Moore ◽  
CM Leigh ◽  
WG Breed
Keyword(s):  
Vas Deferens ◽  
Core Body Temperature ◽  
Laboratory Mouse ◽  
Body Cavity ◽  
Sperm Storage ◽  
The Body ◽  
Cool Temperature ◽  
Main Site ◽  
Cauda Epididymidis ◽  
Common Laboratory

The cauda epididymidis, with its relatively cool temperature (32-35 degrees C), is considered to be the main site of sperm storage in male mammals. However, in the adult male spinifex hopping mouse, Notomys alexis, similar numbers of spermatozoa are found in the vas deferens to those in the cauda epididymidis. The present study shows that, unlike in the laboratory mouse in which spermatozoa of the vas deferens are found mainly in the epididymal region of the duct, spermatozoa in the hopping mouse are localized mainly to the middle and urethral regions of the vas deferens which lies in the inguinal and lower abdominal region of the body cavity. After ligation of the vas deferens close to its connection with the epididymis, many spermatozoa in the vas deferens retain the potential for motility for up to 2 weeks, indicating that the viability of spermatozoa is not compromised by being restricted to core body temperature. This urethral region of the vas deferens, in which spermatozoa reside, has a highly divergent structural organization compared with that of common laboratory rodents in which there is an expanded lumen with a network of epithelial folds. Ultrastructural observations of the cells lining the duct indicate that there are not any marked differences in morphology compared with the cells lining the duct in common laboratory murids, but the infoldings of the vas deferens of the hopping mouse are highly vascular which might facilitate supply of oxygen and nutrients to the spermatozoa residing in the lumen.

scholarly journals New Insights into Alterations in PL Proteins Affecting Their Binding to DNA after Exposure of Mytilus galloprovincialis to Mercury—A Possible Risk to Sperm Chromatin Structure?

2021 ◽  
Vol 22 (11) ◽  
pp. 5893
Author(s):  
Gennaro Lettieri ◽  
Rosaria Notariale ◽  
Nadia Carusone ◽  
Antonella Giarra ◽  
Marco Trifuoggi ◽  
...  
Keyword(s):  
Fluorescence Spectroscopy ◽  
Conformational Changes ◽  
Mytilus Galloprovincialis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Reproductive Activity ◽  
Structural Rearrangement ◽  
Sperm Chromatin ◽  
Sperm Nuclei ◽  
Protein Alterations

Mercury (Hg) is a highly toxic and widespread pollutant. We previously reported that the exposure of Mytilus galloprovincialis for 24 h to doses of HgCl2 similar to those found in seawater (range 1–100 pM) produced alterations in the properties of protamine-like (PL) proteins that rendered them unable to bind and protect DNA from oxidative damage. In the present work, to deepen our studies, we analyzed PL proteins by turbidimetry and fluorescence spectroscopy and performed salt-induced release analyses of these proteins from sperm nuclei after the exposure of mussels to HgCl2 at the same doses. Turbidity assays indicated that mercury, at these doses, induced PL protein aggregates, whereas fluorescence spectroscopy measurements showed mercury-induced conformational changes. Indeed, the mobility of the PLII band changed in sodium dodecyl sulphate-polyacrylamide gel electrophoresis, particularly after exposure to 10-pM HgCl2, confirming the mercury-induced structural rearrangement. Finally, exposure to HgCl2 at all doses produced alterations in PL-DNA binding, detectable by DNA absorption spectra after the PL protein addition and by a decreased release of PLII and PLIII from the sperm nuclei. In conclusion, in this paper, we reported Hg-induced PL protein alterations that could adversely affect mussel reproductive activity, providing an insight into the molecular mechanism of Hg-related infertility.

scholarly journals A histone variant condenses flowering plant sperm via chromatin phase separation

2021 ◽  
Author(s):  
Toby Buttress ◽  
Shengbo He ◽  
Liang Wang ◽  
Shaoli Zhou ◽  
Lei Sun ◽  
...  
Keyword(s):  
Chromatin Condensation ◽  
Ectopic Expression ◽  
Histone Variant ◽  
Flowering Plant ◽  
Sperm Chromatin ◽  
Nuclear Condensation ◽  
Unknown Mechanism ◽  
Evolutionary Innovation ◽  
Active Transcription ◽  
Sperm Nuclei

Sperm chromatin is typically transformed by protamines into a compact and transcriptionally inactive state. Flowering plant sperm cells lack protamines, yet have small, transcriptionally active nuclei with chromatin condensed by an unknown mechanism. Here we show that a histone variant, H2B.8, mediates sperm chromatin and nuclear condensation in Arabidopsis thaliana. Loss of H2B.8 causes enlarged sperm nuclei with dispersed chromatin, whereas ectopic expression in somatic cells produces smaller nuclei with aggregated chromatin, demonstrating that H2B.8 is sufficient for chromatin condensation. H2B.8 aggregates transcriptionally inactive AT-rich chromatin into phase-separated condensates, thus achieving nuclear compaction without reducing transcription. H2B.8 also intermixes inactive AT-rich chromatin and GC-rich pericentromeric heterochromatin, altering higher-order chromatin architecture. Altogether, our results reveal a novel mechanism of nuclear compaction via global aggregation of unexpressed chromatin. We propose that H2B.8 is a flowering plant evolutionary innovation that achieves nuclear condensation compatible with active transcription.

scholarly journals Key gene regulatory sequences with distinctive ontological signatures associate with differentially endonuclease-accessible mouse sperm chromatin

Reproduction ◽  
2011 ◽  
Vol 142 (1) ◽  
pp. 73-86 ◽  
Author(s):  
Myriam Saida ◽  
David Iles ◽  
Abdul Elnefati ◽  
Martin Brinkworth ◽  
David Miller
Keyword(s):  
In Silico ◽  
Methylation Status ◽  
Micrococcal Nuclease ◽  
Ctcf Binding ◽  
Sperm Chromatin ◽  
Regulatory Sequences ◽  
Fish Analysis ◽  
Gene Promoters ◽  
Mouse Sperm ◽  
Sperm Nuclei

Using a well-established endonuclease-based chromatin dissection procedure in conjunction with both experimental comparative genome hybridisation (CGH) array profiling andin silicodata mining, we show that mouse spermatozoa contain chromatin that is sensitive and resistant to digestion with micrococcal nuclease (MNase). Sequences represented in the micrococcal nuclease digestion solubilised (MNDS) but not the MND insoluble (MNDI) chromatin are strongly enriched in chromosomal regions of high gene density. Furthermore, by fluorescencein situhybridisation (FISH) analysis, we show that MNDS and MNDI DNAs occupy distinct domains of decondensed mouse sperm nuclei that may also retain abundant histones. More detailedin silicoanalysis of CGH probe location in relation to known promoters and sequences recognised by CCCTC binding factor (CTCF) shows a significant excess of both in MNDS chromatin. A functional analysis of gene promoters reveals strong ontological signatures for ion transport on methylated promoters associated with CTCF binding sequences in MNDS chromatin. Sensory perception is the only strong ontological signature present in MNDI chromatin, driven by promoters that are not associated with CTCF regardless of their methylation status.

scholarly journals Drosophila melanogaster male germ line-specific transcripts with autosomal and Y-linked genes.

Genetics ◽  
1993 ◽  
Vol 134 (1) ◽  
pp. 293-308 ◽  
Author(s):  
S R Russell ◽  
K Kaiser
Keyword(s):  
Drosophila Melanogaster ◽  
Y Chromosome ◽  
Germ Line ◽  
Stop Codon ◽  
Chromatin Condensation ◽  
Sperm Chromatin ◽  
Autosomal Gene ◽  
Cdna Clones ◽  
Autosomal Locus ◽  
Functional Protein

Abstract We have identified of set of related transcripts expressed in the germ line of male Drosophila melanogaster. Surprisingly, while one of the corresponding genes is autosomal the remainder are located on the Y chromosome. The autosomal locus, at 77F on chromosome arm 3L, corresponds to the previously described transcription unit 18c, located in the first intron of the gene for an RI subunit of cAMP-dependent protein kinase. The Y chromosome copies have been mapped to region h18-h19 on the cytogenetic map of the Y outside of any of the regions required for male fertility. In contrast to D. melanogaster, where Y-linked copies were found in nine different wild-type strains, no Y-linked copies were found in sibling species. Several apparently Y-derived cDNA clones and one Y-linked genomic clone have been sequenced. The Y-derived genomic DNA shares the same intron/exon structure as the autosomal copy as well as related flanking sequences suggesting that it transposed to the Y from the autosomal locus. However, this particular Y-linked copy cannot encode a functional polypeptide due to a stop codon at amino acid position 72. Divergence among five different cDNA clones ranges from 1.5 to 6% and includes a large number of third position substitutions. We have not yet obtained a full-length cDNA from a Y-linked gene and therefore cannot conclude that the D. melanogaster Y chromosome contains functional protein-coding genes. The autosomal gene encodes a predicted polypeptide with 45% similarity to histones of the H5 class and more limited similarity to cysteine-rich protamines. This protein may be a distant relative of the histone H1 family perhaps involved in sperm chromatin condensation.

The assessment of sperm DNA fragmentation in the saltwater crocodile (Crocodylus porosus)

2017 ◽  
Vol 29 (3) ◽  
pp. 630 ◽  
Author(s):  
S. D. Johnston ◽  
C. López-Fernández ◽  
F. Arroyo ◽  
J. L. Fernández ◽  
J. Gosálvez
Keyword(s):  
Dna Damage ◽  
Dna Fragmentation ◽  
Sperm Chromatin ◽  
Sperm Dna Fragmentation ◽  
Fragmented Dna ◽  
Sperm Dna ◽  
Saltwater Crocodile ◽  
Crocodylus Porosus ◽  
Dispersion Test ◽  
Sperm Nuclei

Herein we report a method of assessing DNA fragmentation in the saltwater crocodile using the sperm chromatin dispersion test (SCDt) after including frozen–thawed spermatozoa in a microgel (Halomax; Halotech DNA, Madrid, Spain). Following controlled protein depletion, which included a reducing agent, sperm nuclei with fragmented DNA showed a homogeneous and larger halo of chromatin dispersion with a corresponding reduced nucleoid core compared with sperm with non-fragmented DNA. The presence of DNA damage was confirmed directly by incorporation of modified nucleotides using in situ nick translation (ISNT) and indirectly by studying the correlation of the SCDt with the results of DNA damage visualisation using a two-tailed comet assay (r = 0.90; P = 0.037). Results of the SCDt immediately following thawing and after 5 h incubation at 37°C in order to induce a range of DNA damage revealed individual crocodile differences in both the baseline level of DNA damage and DNA longevity.

scholarly journals Tolerance of the Mouse Sperm Nuclei to Freeze-Drying Depends on Their Disulfide Status1

2003 ◽  
Vol 69 (6) ◽  
pp. 1859-1862 ◽  
Author(s):  
Takehito Kaneko ◽  
David G. Whittingham ◽  
James W. Overstreet ◽  
Ryuzo Yanagimachi
Keyword(s):  
Freeze Drying ◽  
Mouse Sperm ◽  
Sperm Nuclei
Sign in / Sign up

Export Citation Format

Share Document