Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “mouse testis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources
PubMed2004

CASK is in the mammalian sperm head and is processed during epididymal maturation.

Upon adhesion to the zona pellucida or egg extracellular matrix, sperm undergo regulated exocytosis of the acrosomal vesicle. CASK is an adaptor protein that has been implicated in coupling neuronal cell adhesion to regulated exocytosis. In neurons, this scaffolding molecule is associated with several types of transmembrane receptor complexes and connects cell adhesion molecules with ion channels, the actin cytoskeleton, and the cell's exocytotic machinery. We hypothesized CASK might also be an important link between zona pellucida binding and the sperm acrosome reaction. RT-PCR experiments indicated CASK is transcribed in mouse testis. The full size (120 kDa) CASK protein was present in testis from mouse and pig. Immunoblots of mature porcine and murine sperm revealed that the 120 kDa molecule was much less abundant than in testis but the antibody also recognized a group of smaller proteins migrating at 55-65 kDa. Immunofluorescence experiments indicated both the full length and smaller CASK immunoreactive products were found only in the acrosomal region of spermatids and mature sperm and not in other testicular cell types. CASK immunofluorescence was lost following the acrosome reaction. During epididymal maturation, the abundance of the full size CASK decreased and the CASK fragments increased. These results suggest that CASK may be proteolytically processed during epididymal maturation. Because sperm acquire the ability to bind the zona pellucida, acrosome react, and fertilize eggs during epididymal maturation, CASK processing may play a role in the acquisition of these functions.

Acrosome↗
PubMed2006

A new method for toxicity assays on human and mouse fetal testis.

Exposure to environmental pollutants (EP) is associated with a wide range of toxic effects, in particular in testis development. Uranium is a potential pollutant of nuclear industry and over the last few years, its environmental concentrations have increased. In animals, the current procedures for evaluating the potential developmental toxicity of uranium are based on in vivo studies. These methods do not allow to know the direct effects on testicular cells and are obviously excluded for human experiments. Consequently, we have developed an in vitro culture system of the whole testis. In the present study we characterized and validated this organ culture system in both mouse fetal testes and human fetal testes recovered during the first trimester (6-12 weeks) of gestation. We compared the histological aspect, the number of germ cells and the testosterone production, before and after culture. Testicular architecture and intercellular communications were preserved, and organ culture appears as a powerful method for studying the early development of testicular gametogenesis and steroidogenesis in both species. Thus by using this method we will be able to investigate the effects of uranium on mouse and human developing testis. The mouse model will allow us to determine the dose range of interest without restriction of material.

Animals↗
PubMed2002

Ran, a GTP-binding protein involved in nucleocytoplasmic transport and microtubule nucleation, relocates from the manchette to the centrosome region during rat spermiogenesis.

Ran, a Ras-related GTPase, is required for transporting proteins in and out of the nucleus during interphase and for regulating the assembly of microtubules. cDNA cloning shows that rat testis, like mouse testis, expresses both somatic and testis-specific forms of Ran-GTPase. The presence of a homologous testis-specific form of Ran-GTPase in rodents implies that the Ran-GTPase pathway plays a significant role during sperm development. This suggestions is supported by distinct Ran-GTPase immunolocalization sites identified in developing spermatids. Confocal microscopy demonstrates that Ran-GTPase localizes in the nucleus of round spermatids and along the microtubules of the manchette in elongating spermatids. When the manchette disassembles, Ran-GTPase immunoreactivity is visualized in the centrosome region of maturing spermatids. The circumstantial observation that fractionated manchettes, containing copurified centrin-immunoreactive centrosomes, can organize a three-dimensional lattice in the presence of taxol and GTP, points to the role of Ran-GTPase and associated factors in microtubule nucleation as well as the potential nucleating function of spermatid centrosomes undergoing a reduction process. Electron microscopy demonstrates the presence in manchette preparations of spermatid centrosomes, recognized as such by their association with remnants of the implantation fossa, a dense plate observed only at the basal surface of developing spermatid and sperm nuclei. In addition, we have found importin beta1 immunoreactivity in the nucleus of elongating spermatids, a finding that, together with the presence of Ran-GTPase in the nucleus of round spermatids and the manchette, suggest a potential role of Ran-GTPase machinery in nucleocytoplasmic transport. Our expression and localization analysis, correlated with functional observations in other cell systems, suggest that Ran-GTPase may be involved in both nucleocytoplasmic transport and microtubules assembly, two critical events during the development of functional sperm. In addition, the manchette-to-centrosome Ran-GTPase relocation, together with the similar redistribution of various proteins associated to the manchette, suggest the existence of an intramanchette molecular transport mechanism, which may share molecular analogies with intraflagellar transport.

Amino Acid Sequence↗
PubMed1994

Primary structure and expression of a human CTP:phosphocholine cytidylyltransferase.

Human CTP:phosphocholine cytidylyltransferase (CT) cDNAs were isolated by PCR amplification of a human erythroleukemic K562 cell library. Initially two degenerate oligonucleotide primers derived from the sequence of the rat liver CT cDNA were used to amplify a centrally located 230 bp fragment. Subsequently overlapping 5' and 3' fragments were amplified, each using one human CT primer and one vector-specific primer. Two cDNAs encoding the entire translated domain were also amplified. The human CT (HCT) has close homology at the nucleotide and amino acid level with other mammalian CTs (from rat liver, mouse testis or mouse B6SutA hemopoietic cells and Chinese hamster ovary). The region which deviates most from the rat liver CT sequence is near the C-terminus, where 7 changes are clustered within 34 residues (345-359), of the putative phosphorylation domain. The region of the proposed catalytic domain (residues 75-235) is 100% identical with the rat liver sequence. Significant homology was observed between the proposed catalytic domain of CT and the Saccharomyces cerevisiae MUQ1 gene product, and between the proposed amphipathic alpha-helical membrane binding domains of CT and soybean oleosin, a phospholipid-binding protein. There are several shared characteristics of these amphipathic helices. An approx. 42,000 Da protein was over-expressed in COS cells using a pAX142 expression vector containing one of the full-length HCT cDNA clones. The specific activity of the HCT in COS cell homogenates was the same as that of analogously expressed rat liver CT. The activity of HCT was lipid dependent. The soluble form was activated 3 to 4-fold by anionic phospholipids and by oleic acid or diacylglycerol-containing PC vesicles.

Amino Acid Sequence↗
PubMed2003

SPEER--a new family of testis-specific genes from the mouse.

Differential cloning revealed a partial mRNA sequence expressed in the mouse testis, which on further molecular characterization proved to be a member of a new family of 14 transcribed genes. Six of the genes appear to be expressed pseudogenes. The remainder indicate an open reading frame of approximately 200-220 amino acids encoding proteins with a very high proportion of alpha helical secondary structure, comprising approximately 15% glutamate residues. Because of this property, the family has been named SPErm-associated glutamate (E)-Rich protein (SPEER). Three members were chosen for more detailed characterization: SPEER-1 (pseudogene), SPEER-2, and SPEER-4D. All three are expressed tissue specifically in the testis of mice, with only very weak expression evident in the rat testis but in no other species tested. Using reverse transcription-polymerase chain reaction (RT-PCR), all three transcripts can be detected also in the epididymis, presumably due to the presence of spermatozoa. All three transcripts are expressed to high levels in haploid germ cells at the spermatocyte-spermatid transition. SPEER-1 mRNA is present in the cytoplasm as a sense transcript, SPEER-2 appears to be made mostly as an antisense transcript, whereas SPEER-4D appears to be localized within a subcellular compartment as a conventional sense transcript. Codon usage analysis suggests that all but the pseudogenes can be expressed as protein, confirmed for SPEER-2 and SPEER-4D by in vitro transcription/translation. An antibody raised against a peptide region of SPEER-4D, which probably cross-reacts with other SPEER members, immunohistochemically stains the nuclei of early round spermatids. While there are no true homologies to other proteins in the genome databases, some motifs are present that suggest a relationship to nuclear matrix proteins, implying that the SPEER family is a new group of haploid sperm-specific nuclear factors.

Amino Acid Sequence↗
PubMed1990

Transcription of the testis-specific mouse protamine 2 gene in a homologous in vitro transcription system.

Transcriptionally active nuclear extracts were prepared from mouse testes to study the transcription of the testis-specific mouse protamine 2 (Prm-2) gene in vitro. The testicular system is unique among mammalian in vitro transcription systems in regard to its temperature optimum. In extracts made from prepuberal testes, the temperature optimum for in vitro transcription of Prm-2 is 30 degrees C, similar to somatic in vitro systems. However, in adult testis extracts, the optimum temperature for Prm-2 transcription is 20 degrees C. The different temperature optima seen in vitro for prepuberal and adult testes extracts parallels in vivo physiological temperature sensitivities of the differentiating male germ cells. The testis system also differs from other in vitro transcription systems in its divalent metal cation and ionic strength requirements for optimal transcription. The mouse Prm-2 gene is maximally transcribed at a MgCl2 concentration of 3-5 mM and over a KCl concentration range of 40-100 mM. By using the testis in vitro transcription system to study the Prm-2 gene by deletion analysis, we have determined that positive promotion for the gene lies within the region -170 to -82 from the start of transcription. This region contains a putative Sp-1 binding site. Additional upstream sequences appear to repress Prm-2 transcription in a heterologous transcription system.

Animals↗
PubMed1986

Dibutyryl adenosine cyclic monophosphate regulates differentiation of type A spermatogonia with vitamin A in adult mouse cryptorchid testis in vitro.

Surgically prepared cryptorchid mouse testes containing only type A spermatogonia were cultured with (Bu)2cAMP in combination with vitamin A (retinol). Treatment with (Bu)2cAMP and retinol for 12-24 h and with basal medium for an additional 8 days stimulated mitotic activity in type A spermatogonia and induced differentiation of germ cells. However, (Bu)2cAMP alone did not induce differentiation of type A spermatogonia. Moreover, when cryptorchid testes were treated with (Bu)2cAMP for longer than 3 days in the presence or absence of retinol, differentiation of type A spermatogonia did not take place; disintegration of the seminiferous tubules occurred instead. When the cryptorchid testes were cultured for 24 h in a medium containing a fixed concentration of retinol and varying concentrations of (Bu)2cAMP from 0.001-0.4 mM, there was a dose-dependent increase in the number of differentiated and mitotic germ cells and type A spermatogonia. Likewise, at a fixed dose of (Bu)2cAMP and increasing concentrations of retinol, a dose-dependent increase in the number of differentiated and mitotic germ cells occurred. However, the number of type A spermatogonia was decreased. The addition of puromycin, cycloheximide, and actinomycin D to the medium completely blocked retinol-(Bu)2cAMP-induced differentiation of the germ cells. The present results suggest that cAMP and retinol trigger biochemical events promoting the synthesis of specific macromolecules involved in the proliferation and differentiation of type A spermatogonia.

Animals↗
PubMed1995

Expression of the mouse testis-determining gene Sry in male preimplantation embryos.

The testis-determining factor in the mouse is encoded by the Sry gene on the Y chromosome. Transcripts of this gene have been shown previously to be present in the genital ridge at the beginning of gonadal differentiation (11.5 days post coitum) and in adult testis. In this study, RNA transcripts of the Sry gene are also detected in male blastocyst-stage embryos (3.5 days post coitum) at approximately 40-100 copies per cell, long before overt sex differentiation. These results indicate that preimplantation mouse embryos have sexually dimorphic gene expression at least with respect to Sry transcripts. In addition, at least some of the Sry RNA transcripts in blastocysts are circular, as has been reported for Sry transcripts from adult testis. The appearance of Sry transcripts in blastocysts at this level raises the possibility that sex determination begins earlier during embryonic development than previously thought.

Animals↗
PubMed2006

Two novel transcripts encoding two Ankyrin repeat containing proteins have preponderant expression during the mouse spermatogenesis.

The clone 4921537P18 expressed preponderantly in mouse testis was identified by screening the Riken cDNA database, and two new full-length isoforms of this clone, which were named gsarp1 (Gonad Specific Ankyrin Repeat (ANK) Protein 1) and gsarp2, were found and isolated from mouse testis in the course of the research. Both of the GSARP1 and GSARP2 contain an ANK region circular composed by seven ANKs, and their structural feature is very similar to that of the IkappaB family proteins, while IkappaB proteins associate with the transcription factor NF-kappaB via their ANKs in the NF-kappaB pathway. We investigated the expression pattern at the mRNA level by Reverse transcription PCR. The gsarp1 has high expression level in mouse testis, while has low expression level in the ovary, and the gsarp2 is only expressed in mouse testis. The gsarp1 and gsarp2 begin to be detected at the early and later pachytene stage of meiosis separately, while both have high-expression level at the stage of MI and MII. The result of in situ hybridization reveals that the gsarp1 is primarily expressed in spermatocytes, while gsarp2 is expressed in spermatocytes and spermatids. In view of the structural feature and expression pattern of the GSARP1 and GSARP2, we speculate that they may play a certain role in a signal pathway of meiosis.

Amino Acid Sequence↗
PubMed1993

Molecular identity of a sperm acrosome antigen recognized by HS-63 monoclonal antibody.

The molecular identity of mouse sperm acrosome antigen recognized by HS-63 monoclonal antibody was analyzed by various biochemical, immunological and molecular biological methods. When its cognate antigen, MSA-63 was isolated from mouse testis by immunoaffinity chromatography, a group of protein spots with wide range of molecular sizes and isoelectric points were identified. Through previous studies, it was established that most of these protein spots were actin-like molecules co-purified with MSA-63 protein from mouse testis. To analyze the molecular size heterogeneity of the isolated MSA-63 proteins, rabbit antisera against a computer-predicted antigenic synthetic peptide (amino acid residue No. 160-171) and a recombinant glutathione S-transferase (GST) fusion protein (GST-63) were raised. These two antisera and those raised against the isolated MSA-63 protein were used as the probes in comparative Western blot assay, indirect immunofluorescent assay and enzyme-linked immunosorbent assay (ELISA). Using ELISA, antisera against GST-63 and computer-predicted antigenic synthetic peptides were shown to cross-react with affinity-isolated MSA-63 protein coated on microwells. However, little immunological cross-reactivity was observed between GST-63 fusion protein and the synthetic peptide. By using a Western blot assay, two major protein bands of 22 and 32 kDa, respectively were commonly detected on mouse testis homogenate strips by both anti-MSA-63 and anti-GST-63. In addition, anti-MSA-63 also recognized several protein bands with molecular masses greater than 35 kDa. The results of this study suggested that the molecular heterogeneity of MSA-63 protein isolated from mouse testis and sperm, is due to a series of post-translational modifications on a single gene product. These modifications may include glycosylations, proteolytic digestions and tight non-covalent associations with other testicular cytoskeletal proteins, such as actins.

Acrosome↗
PubMed2004

Identification of a novel gene SRG4 expressed at specific stages of mouse spermatogenesis.

Spermatogenesis is a complex process. Two spermatocytes expression sequence tags (ESTs) BG101130 and BG100990 were found. Their putative amino acid sequences have high homology with rat Spag4 (sperm antigen 4). By electrical hybridization, a novel cDNA encoding polypeptide of 348 amino acid residues was identified from a mouse testis cDNA library. The new gene was designated as SRG4 (Spermatogenesis related gene 4) (GenBank accession No. AY307077). Results of Northern blot and RTPCR revealed that SRG4 expressed specifically in mouse testis. Changes of SRG4 expression in mouse different development stages were observed by RT-PCR. The SRG4 mRNA was hardly detected in 2 weeks postpartum, and expressed abundantly from 3 weeks later, reaching top lever at 4-5 weeks, while slightly down in aging mouse testis. Results of in situ hybridization showed that SRG4 gene expressed abundantly in spermatocytes, round spermatids. This indicated SRG4 gene may play an important role in mouse meiotic divisions of spermatocytes.

Amino Acid Sequence↗
PubMed2006

Detection of quantitative trait loci causing abnormal spermatogenesis and reduced testis weight in the small testis (Smt) mutant mouse.

The small testis (Smt) mutant mouse is characterized by a small testis of one third to one half the size of a normal testis, and its spermatogenesis is mostly arrested at early stages of meiosis, although a small number of spermatocytes at the late prophase of meiosis and a few spermatids can sometimes be seen. We performed quantitative trait locus (QTL) analysis of these spermatogenic traits and testis weight using 221 F2 males obtained from a cross between Smt and MOM (Mus musculus molossinus) mice. At the genome-wide 5% level, we detected two QTLs affecting meiosis on chromosomes 4 and 13, and two QTLs for paired testis weight as a percentage of body weight on chromosomes 4 and X. In addition, we found several QTLs for degenerated germ cells and multinuclear giant cells on chromosomes 4, 7 and 13. Interestingly, for cell degeneration, the QTL on chromosome 13 interacted epistatically with the QTL on chromosome 4. These results reveal polygenic participation in the abnormal spermatogenesis and small testis size in the Smt mutant.

Animals↗
PubMed1987

Testis-specific transcripts detected by a human Y-DNA-derived probe.

A genomic sequence (12f3), derived from the long arm of the human Y chromosome, detects a 1.6 kb mRNA, expressed in human and mouse testis, but not in other tissues tested by Northern blot analysis. Using 12f3 as a probe, a mouse cDNA, designated PL5, was isolated from an adult mouse testis cDNA library. The profile obtained by Southern blot analysis using PL5 as probe under high-stringency conditions, reveals that 12f3 probably represents a Y-located pseudogene which was derived from an autosomally located gene. Southern blot analysis of different vertebrate species, using probe PL5, shows that this gene has been highly conserved during evolution. Preliminary in situ hybridizations on testis tissue sections indicate that PL5 is expressed during the postmeiotic stages of male germ cell differentiation and thus may play a role during spermatogenesis. A second cDNA, also obtained from the testis cDNA library, weakly cross-reacts with 12f3. This cDNA, designated PL10, detects a mRNA of approximately 4 kb which is highly expressed in mouse testis, but not in male or female mouse liver. The gene corresponding to this cDNA is also well conserved among vertebrates.

Chromosome Mapping↗
PubMed2005

Genome-scale analysis of positional clustering of mouse testis-specific genes.

BACKGROUND: Genes are not randomly distributed on a chromosome as they were thought even after removal of tandem repeats. The positional clustering of co-expressed genes is known in prokaryotes and recently reported in several eukaryotic organisms such as Caenorhabditis elegans, Drosophila melanogaster, and Homo sapiens. In order to further investigate the mode of tissue-specific gene clustering in higher eukaryotes, we have performed a genome-scale analysis of positional clustering of the mouse testis-specific genes. RESULTS: Our computational analysis shows that a large proportion of testis-specific genes are clustered in groups of 2 to 5 genes in the mouse genome. The number of clusters is much higher than expected by chance even after removal of tandem repeats. CONCLUSION: Our result suggests that testis-specific genes tend to cluster on the mouse chromosomes. This provides another piece of evidence for the hypothesis that clusters of tissue-specific genes do exist.

Animals↗
PubMed2004

[Cloning of cDNA of SRG4, a mouse spermatogenesis related gene and expression in mouse different developing stages].

Spermatogenesis required lots of genes taking part in this process. In prevision studies, Odf1, Odf2, Sak57, Spag4, Spag5 were identified in mouse and rat sperm tail developing. Two ESTs, BG101130 and BG100990, which coded amino acid sequences with high homology to rat Spag4, were found from mouse spermatocytes. By electrical hybridization, a 1 155 bp sequence was obtained and named as SRG4 (Spermatogenesis Related Gene 4) (GenBank accession number: AY307077), which included the full-length sequence of mouse testis hypothetical gene AK006225. The opening reading frame of SRG4 was 87 approximately 1 133 bp, and was proved by RT-PCR in mouse testis. The information analysis showed SRG4 gene was located in 2H1-H2, and the putative protein was 348-amino acid with a coiled-coil region, suggesting SRG4 might function as a transmembrane protein. The homologies of amino acid sequences were 74% between TSARG4 and SRG4 gene and 45% between SRG4 and rat Spag4 gene, respectively. RT-PCR and Northern blot results showed SRG4 gene expressed specifically in mouse testis. Changes of SRG4 expression in mouse different developing stages were observed. The results showed SRG4 gene expressed slightly in two weeks postpartum, and expressed abundantly from three weeks, and reached the top at 4 -5 weeks. This indicted SRG4 gene may play an important role in mouse spermatogenesis.

Amino Acid Sequence↗
PubMed2000

Ectopic activation of the transcription promoter for the testis-specific mouse Pgk-2 gene on elimination of a cis-acting upstream DNA region.

Transgenic mice carrying the coding sequence of beta-galactosidase, for which expression was driven by various upstream regions including the transcription promoter of the testis-specific mouse Pgk-2 gene, were generated. Expression of beta-galactosidase mRNA driven by the region between nucleotide positions -1404 and +61, with respect to the transcription initiation site numbered +1, was examined by reverse transcription-mediated polymerase chain reaction, blot hybridization and in situ hybridization, and compared with that of endogenous Pgk-2 mRNA. The results revealed that the 1.4kb DNA region is sufficient for determining the organ-specific, developmental stage-specific and spermatogenic stage-specific transcription of the mouse Pgk-2 gene. When the region between -684 and +61 was used to generate transgenic mice, beta-galactosidase mRNA was detectable not only in the testis, but also in other organs such as brain and lung. However, the timing and cell-type specificity of testicular expression of beta-galactosidase mRNA were retained in these mice. Because the region between -1404 and -685 repressed the Pgk-2 promoter in somatic cell-derived cell lines, it is suggested that the organ specificity of Pgk-2 transcription is achieved at least partly by negative regulation.

Animals↗
PubMed1997

Identification of a promoter region generating Sry circular transcripts both in germ cells from male adult mice and in male mouse embryonal gonads.

The mouse testis determining gene Sry is expressed in somatic cells of the differentiating male gonad as a linear transcript, encoding a transcription factor containing an HMG box. In the adult mouse testis, Sry expression occurs in meiotic and postmeiotic germ cells. The mouse genomic Sry locus is characterized by two arms of a large inverted repeat, flanking a unique region that, between an acceptor and a donor splice site, contains a single exon encoding the Sry protein. In germ cells from the adult mouse testis, Sry RNA is a circular molecule, which is generated by an inverted splicing event that utilizes the above-mentioned splice sites. Thus, a circular exon is spliced out starting from a large linear RNA precursor containing both arms of the inverted repeat, which pair and generate a large stem-loop structure. Using reverse transcription-polymerase chain reaction and an RNase protection assay, we have now mapped the 5' end of this precursor RNA in the 5' arm of the inverted repeat. Gel mobility shift assay and in vitro transcription with nuclear extracts from adult germ cells further confirm that a region immediately 5' upstream of two transcriptional initiation sites of the precursor RNA contains a promoter sequence in which two consensus Sry binding sequences are specifically recognized by nuclear factors present in adult germ cells but not in Sertoli cells. We also show that the linear precursor of the Sry circular transcript and its splicing product are specifically expressed not only in adult germ cells but also in male embryonal gonads between 11.5 and 13.5 days postcoitum, immediately after the expression of the linear transcript starting from the unique region.

Animals↗
PubMed2007

Identification of a heat-shock protein Hsp40, DjB1, as an acrosome- and a tail-associated component in rodent spermatozoa.

Iba1 is a 17-kDa EF-hand protein highly expressed in the cytoplasm of elongating spermatids in testis. Using Iba1 as a bait, we performed yeast Two-hybrid screening and isolated a heat-shock protein Hsp40, DjB1, from cDNA library of mouse testis. To characterize DjB1 that is encoded by Dnajb1 gene, we carried out immunoblot analyses, in situ hybridization, and immunohistochemistry. Immunoblot analyses showed that DjB1was constitutively expressed in mouse testis and that its expression level was not changed by heat shock. Dnajb1 mRNA was exclusively expressed in spermatocytes and round spermatids in mouse testis, and Dnajb1 protein DjB1 was predominantly expressed in the cytoplasm of spermatocytes, round spermatids, and elongating spermatids. In mature mouse spermatozoa, DjB1 was localized in the middle and the end pieces of flagella as well as in association with the head (acrosomal region). Association of DjB1 with the acrosomal region in sperm head was also observed in rat spermatozoa. These data suggested that DjB1, which was constitutively expressed in postmeiotic spermatogenic cells in testis, was integrated into spermatozoa as at least two components, that is, sperm head and tail of rodent spermatozoa.

Acrosome Reaction↗