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Garretson A, Dumont BL, Handel MA. Reproductive genomics of the mouse: implications for human fertility and infertility. Development 2023; 150:dev201313. [PMID: 36779988 PMCID: PMC10836652 DOI: 10.1242/dev.201313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Genetic analyses of mammalian gametogenesis and fertility have the potential to inform about two important and interrelated clinical areas: infertility and contraception. Here, we address the genetics and genomics underlying gamete formation, productivity and function in the context of reproductive success in mammalian systems, primarily mouse and human. Although much is known about the specific genes and proteins required for meiotic processes and sperm function, we know relatively little about other gametic determinants of overall fertility, such as regulation of gamete numbers, duration of gamete production, and gamete selection and function in fertilization. As fertility is not a binary trait, attention is now appropriately focused on the oligogenic, quantitative aspects of reproduction. Multiparent mouse populations, created by complex crossing strategies, exhibit genetic diversity similar to human populations and will be valuable resources for genetic discovery, helping to overcome current limitations to our knowledge of mammalian reproductive genetics. Finally, we discuss how what we know about the genomics of reproduction can ultimately be brought to the clinic, informing our concepts of human fertility and infertility, and improving assisted reproductive technologies.
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Affiliation(s)
- Alexis Garretson
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Tufts University, Graduate School of Biomedical Sciences, 136 Harrison Ave, Boston, MA 02111, USA
| | - Beth L. Dumont
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Tufts University, Graduate School of Biomedical Sciences, 136 Harrison Ave, Boston, MA 02111, USA
| | - Mary Ann Handel
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Tufts University, Graduate School of Biomedical Sciences, 136 Harrison Ave, Boston, MA 02111, USA
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2
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Protein-tyrosine kinase signaling in the biological functions associated with sperm. JOURNAL OF SIGNAL TRANSDUCTION 2012; 2012:181560. [PMID: 23209895 PMCID: PMC3503396 DOI: 10.1155/2012/181560] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 05/17/2012] [Accepted: 05/31/2012] [Indexed: 01/07/2023]
Abstract
In sexual reproduction, two gamete cells (i.e., egg and sperm) fuse (fertilization) to create a newborn with a genetic identity distinct from those of the parents. In the course of these developmental processes, a variety of signal transduction events occur simultaneously in each of the two gametes, as well as in the fertilized egg/zygote/early embryo. In particular, a growing body of knowledge suggests that the tyrosine kinase Src and/or other protein-tyrosine kinases are important elements that facilitate successful implementation of the aforementioned processes in many animal species. In this paper, we summarize recent findings on the roles of protein-tyrosine phosphorylation in many sperm-related processes (from spermatogenesis to epididymal maturation, capacitation, acrosomal exocytosis, and fertilization).
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3
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Abstract
Drosophila melanogaster spermatids undergo dramatic morphological changes as they differentiate from small round cells approximately 12 μm in diameter into highly polarized, 1.8 mm long, motile sperm capable of participating in fertilization. During spermiogenesis, syncytial cysts of 64 haploid spermatids undergo synchronous differentiation. Numerous changes occur at a subcellular level, including remodeling of existing organelles (mitochondria, nuclei), formation of new organelles (flagellar axonemes, acrosomes), polarization of elongating cysts and plasma membrane addition. At the end of spermatid morphogenesis, organelles, mitochondrial DNA and cytoplasmic components not needed in mature sperm are stripped away in a caspase-dependent process called individualization that results in formation of individual sperm. Here, we review the stages of Drosophila spermiogenesis and examine our current understanding of the cellular and molecular mechanisms involved in shaping male germ cell-specific organelles and forming mature, fertile sperm.
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Affiliation(s)
- Lacramioara Fabian
- Cell Biology Program; The Hospital for Sick Children (SickKids); Toronto, ON Canada
| | - Julie A. Brill
- Cell Biology Program; The Hospital for Sick Children (SickKids); Toronto, ON Canada
- Department of Molecular Genetics; University of Toronto; Toronto, ON Canada
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4
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Clemente EJ, Furlong RA, Loveland KL, Affara NA. Gene expression study in the juvenile mouse testis: identification of stage-specific molecular pathways during spermatogenesis. Mamm Genome 2006; 17:956-75. [PMID: 16964443 DOI: 10.1007/s00335-006-0029-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Accepted: 05/11/2006] [Indexed: 01/30/2023]
Abstract
A gene expression time course in the juvenile mouse testis was established using cDNA microarrays derived from a variety of isolated testis cell types. In conjunction with the use of four germ cell-deficient mouse models, a stage and cell-type classification over nine time points has been obtained and analyzed for differential expression of genes. The expression profiles have been clustered into nine groups and subjected to detailed analysis of associated gene ontology. This has allowed the correlation of particular cellular processes and functions with different expression clusters. Focused analysis of transcripts involved in cell number regulation (apoptosis and proliferation) and their spatiotemporal expression patterns are presented. The findings indicate that for genes involved in both apoptosis and proliferation, several distinct pathways regulating these processes are active in somatic and germ cell lineages.
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Affiliation(s)
- Emily J Clemente
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom
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5
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Abstract
Meiosis is a unique form of cellular division by which a diploid cell produces genetically distinct haploid gametes. Initiation and regulation of mammalian meiosis differs between the sexes. In females, meiosis is initiated during embryo development and arrested shortly after birth during prophase I. In males, spermatogonial stem cells initiate meiosis at puberty and proceed through gametogenesis with no cell cycle arrest. Mouse genes required for early meiotic cell cycle events are being identified by comparative analysis with other eukaryotic systems, by virtue of gene knockout technology and by mouse mutagenesis screens for reproductive defects. This review focuses on mouse reproductive biology and describes the available mouse mutants with defects in the early meiotic cell cycle and prophase I regulatory events. These research tools will permit rapid advances in such medically relevant research areas as infertility, embryo lethality and developmental abnormalities.
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Affiliation(s)
- Changanamkandath Rajesh
- Department of Physiology and Cardiovascular Genomics, Medical University of Ohio, Toledo 43614, USA
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6
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Campbell PK, Waymire KG, Heier RL, Sharer C, Day DE, Reimann H, Jaje JM, Friedrich GA, Burmeister M, Bartness TJ, Russell LD, Young LJ, Zimmer M, Jenne DE, MacGregor GR. Mutation of a Novel Gene Results in Abnormal Development of Spermatid Flagella, Loss of Intermale Aggression and Reduced Body Fat in Mice. Genetics 2002; 162:307-20. [PMID: 12242242 PMCID: PMC1462267 DOI: 10.1093/genetics/162.1.307] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
ROSA22 male mice are sterile due to a recessive gene-trap mutation that affects development of the spermatid flagellum. The defect involves the flagellar axoneme, which becomes unstable around the time of its assembly. Despite a subsequent complete failure in flagellar assembly, development of the spermatid head appears normal and the spermatid head is released at the correct stage in spermatogenesis. The mutation is pleiotropic. Although ROSA22 homozygote males have normal levels of circulating testosterone and display normal mating behavior, they do not exhibit intermale aggressive behavior and have reduced body fat. The mutated gene (Gtrgeo22) maps to mouse chromosome 10 and is closely flanked by two known genes, Madcam1 and Cdc34. Ribonuclease protection analysis indicates that expression of the flanking genes is unaffected by the mutation. Gtrgeo22 is expressed at low levels in epithelial cells in several tissues, as well as in testis and brain. Analysis of the peptide coding sequence suggests that Gtrgeo22 encodes a novel transmembrane protein, which contains dileucine and tyrosine-based motifs involved in intracellular sorting of transmembrane proteins. Analysis of the Gtrgeo22 gene product should provide novel insight into the molecular basis for intermale aggression and sperm flagellar development.
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7
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Bhasin S, Mallidis C, Ma K. The genetic basis of infertility in men. BAILLIERE'S BEST PRACTICE & RESEARCH. CLINICAL ENDOCRINOLOGY & METABOLISM 2000; 14:363-88. [PMID: 11097781 DOI: 10.1053/beem.2000.0085] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Subfertility in men is a heterogeneous syndrome, its pathophysiology remaining unknown in the majority of affected men. A large number of genes and loci are associated with sterility in experimental animals, but the human homologues of most of these genes have not been characterized. A British study suggested that, in a large proportion of men with idiopathic infertility, the disorder is inherited as an autosomal recessive trait; this provocative hypothesis needs confirmation. Because normal germ cell development requires the temporally and spatially co-ordinated expression of a number of gene products at the hypothalamic, pituitary and testicular levels, it is safe to predict that a large number of autosomal, as well as X- and Y-linked, genes will probably be implicated in different subsets of male subfertility.
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Affiliation(s)
- S Bhasin
- UCLA School of Medicine, CA 90059, USA
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8
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Tarsounas M, Pearlman RE, Moens PB. Meiotic activation of rat pachytene spermatocytes with okadaic acid: the behaviour of synaptonemal complex components SYN1/SCP1 and COR1/SCP3. J Cell Sci 1999; 112 ( Pt 4):423-34. [PMID: 9914155 DOI: 10.1242/jcs.112.4.423] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The phosphatase inhibitor okadaic acid accelerates meiotic events in rodent germ cells in culture. Isolated pachytene spermatocytes treated with okadaic acid proceed to a metaphase I arrest in a few hours as opposed to the similar process in vivo, which requires several days. Leptotene/zygotene spermatocytes cannot be activated in this way, suggesting that okadaic acid enables cells to bypass a sensor of the meiotic progression, which is pachytene specific. We monitored the chromosome behaviour accompanying the transition to metaphase I in rat spermatocytes with antibodies against COR1/SCP3, a component of the meiotic chromosome cores, and against the synaptic protein, SYN1/SCP1. Okadaic acid induced a rapid synaptonemal complex dissolution and bivalent separation, followed by chromosome condensation and chiasmata formation, similar to the succession of events in untreated cells. The similarity between meiosis I induced with okadaic acid and the meiosis I events in vivo extends to the dissolution of the nuclear membrane and the disappearance of the microtubule network at the onset of metaphase I. This cell culture system provides a model for the in vivo transition from pachytene to metaphase I and therefore can be used in the study of this transition at the molecular level. The effect of okadaic acid is most likely mediated by the activation of tyrosine kinases, as addition of genistein, a general tyrosine kinase inhibitor, completely abolishes the observed effect of okadaic acid on chromosome metabolism. The okadaic acid-induced progression to the metaphase I arrest is not affected by the inhibition of protein synthesis. However, pachytene spermatocytes incubated in the presence of protein synthesis inhibitors for 6 hours show loss of synapsis which is abnormal in that it is not accompanied by chiasmata formation. The two meiosis-specific proteins, SYN1/SCP1 and COR1/SCP3, are efficiently phosphorylated in vitro by extracts from isolated pachytene cells. Extracts from cells that have reached metaphase I upon okadaic acid treatment, with concomitant displacement of SYN1/SCP1 and COR1/SCP3 from their chromosomes, do not have this capability. These data support the hypothesis that phosphorylation of SYN1/SCP1 and COR1/SCP3 targets their removal from the chromosomes and that activity of the kinases involved correlates with the presence of these two proteins on the chromosomes.
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Affiliation(s)
- M Tarsounas
- Department of Biology, York University, Toronto, Ontario, M3J 1P3 Canada.
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9
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Bhasin S, Ma K, Sinha I, Limbo M, Taylor WE, Salehian B. The genetic basis of male infertility. Endocrinol Metab Clin North Am 1998; 27:783-805, viii. [PMID: 9922908 DOI: 10.1016/s0889-8529(05)70041-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Defective spermatogenesis can be the end result of a multitude of causes, such as systemic disease, malnutrition, endocrinologic disorder, genetic defects, anatomic obstruction of the passage of spermatozoa, infections, and environmental toxins. A genetic basis of infertility is thought to exist in a majority of infertile men currently classified as having idiopathic infertility. Despite advances in molecular technology, the pathophysiology of spermatogenic failure in a majority of infertile men remains unknown. Although a large number of genes and loci in experimental animals are associated with sterility, the human homologues of most of these genes have not been cloned yet. Infertility is a heterogeneous syndrome in men; therefore, it is likely that a multitude of genes and loci will be implicated in different infertility subsets.
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Affiliation(s)
- S Bhasin
- Division of Endocrinology, Metabolism and Molecular Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, California, USA
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10
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Hecht NB. Molecular mechanisms of male germ cell differentiation. Bioessays 1998. [PMID: 9723004 DOI: 10.1002/(sici)1521-1878(199807)20:7%3c555::aid-bies6%3e3.0.co;2-j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
During spermatogenesis, diploid stem cells differentiate, undergo meiosis, and transform into haploid spermatozoa. As this precisely timed series of events proceeds, chromosomal ploidy is reduced and the nucleosomes of the chromatin are replaced by a transcriptionally quiescent protamine-containing nucleus. The premature termination of transcription during the haploid phase of spermatogenesis necessitates an especially prominent role for posttranscriptional regulation in the temporal and spatial expression of many testis-specific proteins and isozymes. In this review article, discussion will focus on novel mechanisms regulating gene expression in mammalian male germ cells from genome to protein.
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Affiliation(s)
- N B Hecht
- Center for Research on Reproduction and Women's Health, Philadelphia, PA, USA.
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11
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Abstract
During spermatogenesis, diploid stem cells differentiate, undergo meiosis, and transform into haploid spermatozoa. As this precisely timed series of events proceeds, chromosomal ploidy is reduced and the nucleosomes of the chromatin are replaced by a transcriptionally quiescent protamine-containing nucleus. The premature termination of transcription during the haploid phase of spermatogenesis necessitates an especially prominent role for posttranscriptional regulation in the temporal and spatial expression of many testis-specific proteins and isozymes. In this review article, discussion will focus on novel mechanisms regulating gene expression in mammalian male germ cells from genome to protein.
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Affiliation(s)
- N B Hecht
- Center for Research on Reproduction and Women's Health, Philadelphia, PA, USA.
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12
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McKee BD, Wilhelm K, Merrill C, Ren X. Male sterility and meiotic drive associated with sex chromosome rearrangements in Drosophila. Role of X-Y pairing. Genetics 1998; 149:143-55. [PMID: 9584092 PMCID: PMC1460153 DOI: 10.1093/genetics/149.1.143] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In Drosophila melanogaster, deletions of the pericentromeric X heterochromatin cause X-Y nondisjunction, reduced male fertility and distorted sperm recovery ratios (meiotic drive) in combination with a normal Y chromosome and interact with Y-autosome translocations (T(Y;A)) to cause complete male sterility. The pericentromeric heterochromatin has been shown to contain the male-specific X-Y meiotic pairing sites, which consist mostly of a 240-bp repeated sequence in the intergenic spacers (IGS) of the rDNA repeats. The experiments in this paper address the relationship between X-Y pairing failure and the meiotic drive and sterility effects of Xh deletions. X-linked insertions either of complete rDNA repeats or of rDNA fragments that contain the IGS were found to suppress X-Y nondisjunction and meiotic drive in Xh-/Y males, and to restore fertility to Xh-/T(Y;A) males for eight of nine tested Y-autosome translocations. rDNA fragments devoid of IGS repeats proved incapable of suppressing either meiotic drive or chromosomal sterility. These results indicate that the various spermatogenic disruptions associated with X heterochromatic deletions are all consequences of X-Y pairing failure. We interpret these findings in terms of a novel model in which misalignment of chromosomes triggers a checkpoint that acts by disabling the spermatids that derive from affected spermatocytes.
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Affiliation(s)
- B D McKee
- Department of Biology, University of Wisconsin, Eau Claire, Wisconsin 54702, USA.
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13
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Pittman DL, Cobb J, Schimenti KJ, Wilson LA, Cooper DM, Brignull E, Handel MA, Schimenti JC. Meiotic prophase arrest with failure of chromosome synapsis in mice deficient for Dmc1, a germline-specific RecA homolog. Mol Cell 1998; 1:697-705. [PMID: 9660953 DOI: 10.1016/s1097-2765(00)80069-6] [Citation(s) in RCA: 463] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
DMC1 is a meiosis-specific gene first discovered in yeast that encodes a protein with homology to RecA and may be component of recombination nodules. Yeast dmc1 mutants are defective in crossing over and synaptonemal complex (SC) formation, and arrest in late prophase of meiosis I. We have generated a null mutation in the Dmc1 gene in mice and show that homozygous mutant males and females are sterile with arrest of gametogenesis in the first meiotic prophase. Chromosomes in mutant spermatocytes fail to synapse, despite the formation of axial elements that are the precursor to the SC. The strong similarity of phenotypes in Dmc1-deficient mice and yeast suggests that meiotic mechanisms have been highly conserved through evolution.
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Affiliation(s)
- D L Pittman
- Jackson Laboratory, Bar Harbor, Maine 04609, USA
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14
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Roldan ER, Cassinello J, Abaigar T, Gomendio M. Inbreeding, fluctuating asymmetry, and ejaculate quality in an endangered ungulate. Proc Biol Sci 1998; 265:243-8. [PMID: 9493409 PMCID: PMC1688876 DOI: 10.1098/rspb.1998.0288] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
An ever-increasing number of species are suffering marked reductions in population size as a consequence of human activities. To understand the impact of these changes it is essential to assess how small population size affects individual fitness and the viability of populations. This issue acquires special relevance among endangered species in which numbers have decreased to such an extent that captive breeding must be established with a few founders. A major risk associated with small population size is inbreeding depression. The effects of inbreeding upon male reproductive traits are the subject of an ongoing controversy, since the evidence linking lack of genetic variability and poor ejaculate quality at the population level has been criticized recently by several authors. We report that among Gazella cuvieri males, inbreeding coefficient shows a strong inverse relationship with ejaculate quality. Furthermore, the degree of fluctuating asymmetry is positively related to the coefficient of inbreeding and negatively related to the proportion of normal sperm, suggesting that it is a reliable indicator of genetic stress and of ejaculate quality.
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Affiliation(s)
- E R Roldan
- Instituto de Bioquímica (CSIC-UCM), Ciudad Universitaria, Madrid, Spain
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15
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Abstract
During the pachytene stage of meiotic prophase in male mammals, the X and Y chromosomes become transcriptionally inactive and establish a chromatin domain, the sex body, that is visually distinct from the transcriptionally active autosomes. We used objective criteria to assess these chromatin differences by DNase I sensitivity (DS) of sex chromosome and autosomal sequences at both the cytological and molecular levels. For cytological studies, in situ nick translation techniques were used on air-dried preparations of testicular cells. For molecular studies, nuclei from pachytene spermatocytes were subjected to nuclease sensitivity assays. Both sex-linked and autosomal sequences were assessed, including some gene sequences that are expressed and some that are not expressed in pachytene spermatocytes. There was a wide range of DS in different genomic sequences; however, the sex-linked sequences generally were less nuclease sensitive than were autosomal sequences. Interestingly, a hot spot of recombination (within the Eb gene) showed a high level of nuclease sensitivity, while a cold spot of recombination (centromeric satellite region) exhibited lower sensitivity, more similar to that of sex-linked sequences. We also examined the nuclease sensitivity of a tyrosinase transgene insert, TyBS. In one line of mice, the transgene insert is X-linked, whereas in another, it is autosomal. The transgene was less nuclease sensitive when X-linked than as an autosomal insert. These results support the hypothesis that in pachytene spermatocytes the XY chromosome pair is more condensed and inaccessible to enzymatic digest, whereas the autosomal chromatin is in a more open configuration. In addition, we examined the nuclease sensitivity of some of the same genes in the earlier leptotene/zygotene prophase stage, when the sex chromatin is not maximally condensed. We found that while autosomal gene nuclease sensitivity was equivalent to that at the pachytene stage, X-linked sequences were more nuclease sensitive. Overall, these differences in chromatin nuclease sensitivity correlate with differences in meiotic recombination activity and may be mechanistically related.
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Affiliation(s)
- T Wiltshire
- Dept. of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville 37996-0840, USA
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16
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Burruel VR, Raabe OG, Wiley LM. In vitro fertilization rate of mouse oocytes with spermatozoa from the F1 offspring of males irradiated with 1.0 Gy 137Cs gamma-rays. Mutat Res 1997; 381:59-66. [PMID: 9403031 DOI: 10.1016/s0027-5107(97)00148-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Previous studies suggest that the spermatozoa from acutely irradiated male mice exhibit a reduced fertilization rate in vitro with the maximum decrease occurring for spermatozoa produced 6 weeks after irradiation (Y. Matsuda et al., Mutation Res. 142 (1985) 59-63). We have found that spermatozoa from unirradiated F1 males conceived 6 weeks after paternal F0 irradiation also exhibit a significantly reduced fertilization rate in vitro. After acute 137Cs gamma-irradiation yielding an absorbed dose of 1.0 Gy, adult CD1 F0 male mice were mated at weekly intervals with unirradiated female CD1 mice. Unirradiated adult males from F1 litters conceived 5 and 6 weeks after paternal F0 irradiation were allowed to mature. Their epididymal spermatozoa were evaluated for in vitro fertilization rates using oocytes from unirradiated 8-12-week-old CD1 females. The mean fertilization rate for spermatozoa from F1 males conceived 5 weeks after paternal F0 irradiation (80.74 +/- 15.74 SD %, n = 5) did not differ significantly from the control fertilization rate (89.40 +/- 10.94 SD %, n = 8). However, the fertilization rate for spermatozoa from F1 males conceived 6 weeks after paternal F0 irradiation (56.14 +/- 21.93 SD %, n = 5) was significantly less than the fertilization rate for control spermatozoa (p < 0.006) or for that of the F1 males conceived 5 weeks after paternal F0 irradiation (p < 0.04). These data suggest that spermatozoa obtained 6 weeks after paternal F0 irradiation can transmit a decrease in fertilization rate to the F1 generation males as well as exhibit decreased fertilization rate themselves when tested directly in vitro.
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Affiliation(s)
- V R Burruel
- Department of Obstetrics and Gynecology, School of Medicine, University of California, Davis 95616-8615, USA
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17
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Ward-Bailey PF, Johnson KR, Handel MA, Harris BS, Davisson MT. A new mouse mutation causing male sterility and histoincompatibility. Mamm Genome 1996; 7:793-7. [PMID: 8875885 DOI: 10.1007/s003359900239] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Male sterility and histoincompatibility, mshi, is an autosomal recessive mutation in BALB/cBy mice that causes reduced testis size and sterility in homozygous males. The testes of homozygous mutants are highly disorganized and appear to have a block in the regulation of male germ cell proliferation. No heterozygous effect is detectable. Reproduction is unaffected in females carrying the mutation. The mutation also affects histocompatibility; most homozygous males and females reject sex-matched skin grafts from BALB/cBy mice. We used an intercross between BALB/cBy and CAST/Ei to map the mshi mutation to the proximal end of Chromosome (Chr) 10. The most likely gene order places the mutation between D10Mit80 and D10Mit16, near the interferon gamma receptor locus, Ifgr, which may be a candidate gene for this mutation.
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18
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Tres LL, Kierszenbaum AL. Sak57, an acidic keratin initially present in the spermatid manchette before becoming a component of paraaxonemal structures of the developing tail. Mol Reprod Dev 1996; 44:395-407. [PMID: 8858609 DOI: 10.1002/(sici)1098-2795(199607)44:3<395::aid-mrd13>3.0.co;2-#] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have previously reported that Sak57 (for Spermatogenic cell/Sperm-associated keratin of molecular mass 57 kDa) is an acidic keratin found in rat spermatocytes, spermatids, and sperm. Sak57 displays conserved amino acid sequences found in the 1A and 2A regions of the alpha-helical rod domain of keratins in human, rat, and mouse. We now report indirect immunofluorescence, confocal laser scanning microscopy and immunogold electron microscopy data showing that Sak57 is associated with the microtubular mantie of the manchette, a transient microtubular structure largely regarded as formed by tubulin and microtubule-associated proteins. The immunocytochemical localization of Sak57 was detected with a polyclonal antiserum to a multiple antigenic peptide (MAP) containing an amino acid sequence known to be present in the 2A region of the alpha-helical rod domain. During spermiogenic steps 8-12, Sak57 immunoreactive sites were restricted to microtubular mantie of the manchette which encircles the spermatid nucleus during shaping and chromatin condensation. At later stages (spermiogenic steps 12-14), Sak57 immunoreactive sites in the spermatid head region disappeared gradually as specific immunoreactivity appeared along the already assembled axoneme of the developing spermatid tail. Immunogold electron microscopy confirmed the presence of Sak57 immunoreactivity among microtubules of the manchette and on outer dense fibers and the longitudinal columns linking the ribs of the fibrous sheath. Mature spermatids (spermiogenic step 19) displayed tails with an immunofluorescent banding pattern contrasting with the lack of Sak57 immunoreactivity in the head region. Results from this study suggest that, during early spermiogenesis, a microtubular-Sak57 scaffolding is associated with the spermatid nucleus during shaping and chromatin condensation. During late spermiogenesis, the dispersion of the manchette coincides with the progressive visualization of Sak57 in the paraaxonemal outer dense fibers and longitudinal columns of the fibrous sheath in the developing spermatid tail.
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Affiliation(s)
- L L Tres
- Department of Cell Biology and Anatomical Sciences, City University of New York Medical School, New York 10031, USA
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19
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Kumari M, Stroud JC, Anji A, McCarrey JR. Differential appearance of DNase I-hypersensitive sites correlates with differential transcription of Pgk genes during spermatogenesis in the mouse. J Biol Chem 1996; 271:14390-7. [PMID: 8662942 DOI: 10.1074/jbc.271.24.14390] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Two functional genes encoding phosphoglycerate kinase are differentially expressed during spermatogenesis in the mouse. Expression of the X-linked Pgk-1 gene is repressed coincident with X chromosome inactivation during prophase of meiosis I. At this same stage, expression of the autosomal Pgk-2 gene is initiated by tissue-specific mechanisms. To investigate the role of chromatin structure in these processes, we have examined the appearance and disappearance of DNase I-hypersensitive (DH) sites in each gene, and correlated this with transcriptional activity as measured by nuclear run-off analysis at specific stages of spermatogenesis. Our results demonstrate that the occurrence of DH sites is related to periods of active transcription. Results with the Pgk-1 gene indicate that transcriptional inactivation of the X chromosome in spermatogenic cells may not be as complete as that in somatic cells, and that maximum repression may be limited to a very transient period during the pachytene stage of first meiotic prophase. Results with the Pgk-2 gene indicate that DH sites appear coincident with, or just prior to, transcriptional activation of this gene. The implications of these results are discussed with respect to the role of X chromosome inactivation in spermatogenic cells and the developmental order of molecular events that regulate differential gene expression during spermatogenesis.
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Affiliation(s)
- M Kumari
- Department of Genetics, Southwest Foundation for Biomedical Research, San Antonio, Texas 78245, USA
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20
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Abstract
The goals of this work were to create germ-cell-stage-specific cDNA libraries from mouse spermatogenic cells and to employ a novel two-step genetic screen to identify gene sequences present during the critical meiotic stage of spermatogenesis. Highly enriched germ-cell fractions were prepared from adult and juvenile mouse testes, and purity of these fractions was extensively analyzed by light and electron microscopy. Standard techniques were used to prepare cDNA libraries from populations of mixed leptotene and zygotene (L/Z) spermatocytes, pachytene (P) spermatocytes, and round spermatids. These libraries were analyzed with respect to representation of sequences from ubiquitously expressed genes, and from genes expressed at specific germ-cell stages as well as from genes expressed in testicular somatic cells. For the first step of the screening procedure, testicular cDNA was prepared from mutant mice carrying the T(X;11)38H chromosomal translocation that causes spermatogenic arrest at early meiotic prophase. This mixed cDNA probe was used to screen the libraries from L/Z and P spermatocytes to detect sequences failed to hybridize. The clones identified were characterized for ability to hybridize to various germ-cell-specific cDNAs to verify that they represented sequences present in normal spermatogenic meiotic cells. These clones were then subjected to a second screening with another mutant probe; this time the cDNA probe was from testes of sterile mice bearing the T(X;16)16H chromosomal translocation that causes spermatogenic arrest at late meiotic prophase. This screen identified 27 clones that were not represented in testicular cDNA from T38-bearing mice or from T16-bearing mice. These clones may represent sequences essential for normal completion of the genetic events of meiosis during spermatogenesis. Likewise, the secondary screen identified 19 clones that were not represented in testicular cDNA from T38-bearing mice but were represented in testicular cDNA of T16-bearing mice. These clones are thus gene sequences present in spermatogenic cells during the time from early meiotic prophase to mid-to-late prophase. This strategy represents the first use of genetic aberrations in differential screening to identify genes expressed at specific times during mammalian spermatogenesis.
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Affiliation(s)
- K A Caldwell
- Department of Zoology, University of Tennessee, Knoxville, USA
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21
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Rinchik EM, Carpenter DA, Handel MA. Pleiotropy in microdeletion syndromes: neurologic and spermatogenic abnormalities in mice homozygous for the p6H deletion are likely due to dysfunction of a single gene. Proc Natl Acad Sci U S A 1995; 92:6394-8. [PMID: 7604002 PMCID: PMC41524 DOI: 10.1073/pnas.92.14.6394] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Variability and complexity of phenotypes observed in microdeletion syndromes can be due to deletion of a single gene whose product participates in several aspects of development or can be due to the deletion of a number of tightly linked genes, each adding its own effect to the syndrome. The p6H deletion in mouse chromosome 7 presents a good model with which to address this question of multigene vs. single-gene pleiotropy. Mice homozygous for the p6H deletion are diluted in pigmentation, are smaller than their littermates, and manifest a nervous jerky-gait phenotype. Male homozygotes are sterile and exhibit profound abnormalities in spermiogenesis. By using N-ethyl-N-nitrosourea (EtNU) mutagenesis and a breeding protocol designed to recover recessive mutations expressed hemizygously opposite a large p-locus deletion, we have generated three noncomplementing mutations that map to the p6H deletion. Each of these EtNU-induced mutations has adverse effects on the size, nervous behavior, and progression of spermiogenesis that characterize p6H deletion homozygotes. Because EtNU is thought to induce primarily intragenic (point) mutations in mouse stem-cell spermatogonia, we propose that the trio of phenotypes (runtiness, nervous jerky gait, and male sterility) expressed in p6H deletion homozygotes is the result of deletion of a single highly pleiotropic gene. We also predict that a homologous single locus, quite possibly tightly linked and distal to the D15S12 (P) locus in human chromosome 15q11-q13, may be associated with similar developmental abnormalities in humans.
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Affiliation(s)
- E M Rinchik
- Biology Division, Oak Ridge National Laboratory, TN 37831-8077, USA
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23
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Abstract
Mammalian sex chromosomes exhibit marked sexual dimorphism in behavior during gametogenesis. During oogenesis, the X chromosomes pair and participate in unrestricted recombination; both are transcriptionally active. However, during spermatogenesis the X and Y chromosomes experience spatial restriction of pairing and recombination, are transcriptionally inactive, and form a chromatin domain that is markedly different from that of the autosomes. Thus the male germ cell has to contend with the potential loss of X-encoded gene products, and it appears that coping strategies have evolved. Genetic control of sex-chromosome inactivation during spermatogenesis does not involve pairing or the presence of the Y chromosome or an intact X chromosome, and may therefore be under exogenous control by the gonad. Sex-chromosome reactivation during oogenesis and inactivation during spermatogenesis probably reflect specific meiotic events such as recombination. Understanding these phenomena may help explain other sex-related differences in genetic recombination.
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Affiliation(s)
- M A Handel
- Department of Zoology, University of Tennessee, Knoxville 37996-0810
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24
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Broceño C, Ruiz P, Reina M, Vilaró S, Pons G. The muscle-specific phosphoglycerate mutase gene is specifically expressed in testis during spermatogenesis. EUROPEAN JOURNAL OF BIOCHEMISTRY 1995; 227:629-35. [PMID: 7867621 DOI: 10.1111/j.1432-1033.1995.tb20182.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Spermatogenesis is a dramatic differentiation process which involves very selective but poorly characterized gene-expression patterns. To gain insight into this process, we have investigated the expression during spermatogenesis of the genes that encode phosphoglycerate mutase, an essential glycolytic enzyme for the spermatozoa energy supply. By using cDNA and genomic probes we demonstrate the presence in testis of a mRNA corresponding to the muscle-specific phosphoglycerate mutase which shows a longer poly(A) tail. This muscle-specific gene is submitted to developmental regulation during testis maturation and begins to be expressed at postnatal day 22, when germ cells start to enter into meiosis. Northern blot and in situ hybridization experiments show that in contrast to what happens during skeletal-muscle differentiation, PGAM-M gene expression during spermatogenesis is not coupled to constitutive phosphoglycerate mutase (PGAM-B) gene repression. Thus, the muscle-specific PGAM-M gene constitutes a meiotic gene and therefore represents a very interesting model to study differential tissue-specific gene expression.
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Affiliation(s)
- C Broceño
- Facultat de Medicina, Departament de Ciències Fisiològiques, Universitat de Barcelona, Spain
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25
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Handel MA, Caldwell KA, Wiltshire T. Culture of pachytene spermatocytes for analysis of meiosis. DEVELOPMENTAL GENETICS 1995; 16:128-39. [PMID: 7736663 DOI: 10.1002/dvg.1020160206] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
An impediment to the investigation of mammalian spermatogenic meiosis has been the lack of an appropriate system for experimental manipulation of meiotic prophase cells. We report here the use of a simple system for the short-term culture of pachytene spermatocytes. We have assayed parameters of cell function pertinent to meiotic prophase, namely chromosome pairing and synapsis. During the culture period of 24-48 hr, cells maintained typical pachytene morphology, chromatin condensation patterns, and chromosome pairing, as assessed by light and electron microscopy. Uridine incorporation, monitored by autoradiography, reflected the chromosomal distribution found in vivo in that the autosomal chromosomes were transcriptionally active, while the sex chromosomes were not. Thus features of chromosome pairing and sex chromatin inactivation are maintained in these cultures. We have conducted experiments to demonstrate that cultured pachytene spermatocytes can be useful for the analysis of agents, some of which may be suspected mutagens, that might affect chromosome structure and function during meiosis. Treatment of cells with actinomycin D revealed a differential effect on chromatin condensation in the autosomes versus the sex chromosomes. Camptothecin, a topoisomerase inhibitor, induced desynapsis of paired chromosomes. Okadaic acid, a phosphatase inhibitor, induced premature metaphase-I condensation of pachytene chromosomes. This last experiment suggests that these cultured cells may be useful for analysis of meiotic cell cycle controls. Taken together, these results demonstrate a culture system that can be useful for analysis of meiotic events as well as in screening for potential mutagenic agents that might affect meiotic chromosome structure and function.
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Affiliation(s)
- M A Handel
- Department of Zoology, University of Tennessee, Knoxville 37996-0810, USA
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26
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Affiliation(s)
- N B Hecht
- Department of Biology, Tufts University, Medford, Massachusetts 02155, USA
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27
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28
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Nishimune Y, Okabe M. Mammalian Male Gametogenesis: Growth, Differentiation and Maturation of Germ Cells. (Spermatogenesis/Germ cell/Mutant mouse/Cryptorchidism/Capacitation). Dev Growth Differ 1993. [DOI: 10.1111/j.1440-169x.1993.00479.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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29
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A testis-specific gene encoding a nuclear high-mobility-group box protein located in elongating spermatids. Mol Cell Biol 1993. [PMID: 8321234 DOI: 10.1128/mcb.13.7.4323] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A cDNA encoding a DNA-binding protein has been isolated by screening a mouse testicular expression cDNA library with a concatemer of a 12-bp putative protein-binding element present in the promoter of the testis-specific gene PGK-2. Sequence analysis of the isolated cDNA indicated the presence of an open reading frame that encodes a protein with two conserved DNA-binding motifs known as the high-mobility-group (HMG) boxes. Northern (RNA) blot analysis demonstrated that expression of the gene is restricted to the postpuberal testis. The DNA-binding activity and sequence specificity of the recombinant HMG protein were confirmed by DNA mobility shift assay using the initial concatemer of the PGK-2 promoter element as a probe as well as the wild-type or mutated versions of the 12-bp element within its natural sequence context. Immunocytochemical staining of adult testis sections with polyclonal antisera recognizing this recombinant HMG protein demonstrated that it is located predominantly in the nuclei of elongated spermatids at steps 9 and 10. These results suggest that this novel HMG box protein gene may be involved in the regulation of gene expression of the haploid male genome. The gene from which the cDNA was derived has been termed testis-specific HMG (tsHMG).
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30
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Boissonneault G, Lau YF. A testis-specific gene encoding a nuclear high-mobility-group box protein located in elongating spermatids. Mol Cell Biol 1993; 13:4323-30. [PMID: 8321234 PMCID: PMC359989 DOI: 10.1128/mcb.13.7.4323-4330.1993] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A cDNA encoding a DNA-binding protein has been isolated by screening a mouse testicular expression cDNA library with a concatemer of a 12-bp putative protein-binding element present in the promoter of the testis-specific gene PGK-2. Sequence analysis of the isolated cDNA indicated the presence of an open reading frame that encodes a protein with two conserved DNA-binding motifs known as the high-mobility-group (HMG) boxes. Northern (RNA) blot analysis demonstrated that expression of the gene is restricted to the postpuberal testis. The DNA-binding activity and sequence specificity of the recombinant HMG protein were confirmed by DNA mobility shift assay using the initial concatemer of the PGK-2 promoter element as a probe as well as the wild-type or mutated versions of the 12-bp element within its natural sequence context. Immunocytochemical staining of adult testis sections with polyclonal antisera recognizing this recombinant HMG protein demonstrated that it is located predominantly in the nuclei of elongated spermatids at steps 9 and 10. These results suggest that this novel HMG box protein gene may be involved in the regulation of gene expression of the haploid male genome. The gene from which the cDNA was derived has been termed testis-specific HMG (tsHMG).
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Affiliation(s)
- G Boissonneault
- Division of Cell and Developmental Genetics, University of California, San Francisco 94121
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31
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McCarrey JR, Berg WM, Paragioudakis SJ, Zhang PL, Dilworth DD, Arnold BL, Rossi JJ. Differential transcription of Pgk genes during spermatogenesis in the mouse. Dev Biol 1992; 154:160-8. [PMID: 1426623 DOI: 10.1016/0012-1606(92)90056-m] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have analyzed the occurrence of transcripts produced from the ubiquitously expressed, X-linked Pgk-1 gene and the testis-specific, autosomal Pgk-2 gene during spermatogenesis in the mouse. We found that tissue specificity, developmental specificity, and cell-type specificity of these mRNAs parallel that previously reported for the two protein isozymes of phosphoglycerate kinase (PGK) encoded by these two genes. This indicates that primary regulation of differential expression of the Pgk genes during spermatogenesis is exerted at the transcriptional level. We first detected Pgk-2 mRNA in preleptotene spermatocytes, indicating that transcription of Pgk-2 is initiated coincident with the onset of meiosis in male germ cells, and then continues to increase in later spermatocytes and postmeiotic round spermatids. This expression initiates prior to an initial decline in Pgk-1 transcript levels observed in pachytene spermatocytes, which apparently follows inactivation of the single X chromosome in spermatogenic cells. However, unlike cessation of Pgk-1 transcription from the inactivated X chromosome in female somatic cells, we show that inactivation of the Pgk-1 locus in spermatogenic cells is not followed by methylation of a key CpG dinucleotide in the promoter region. These results support the idea that specific expression of the Pgk-2 gene in meiotic and postmeiotic spermatogenic cells has evolved to compensate for reduced levels of Pgk-1 gene product caused by transient X-chromosome inactivation in these cells. They further suggest that reinitiation of transcription of the paternal Pgk-1 allele shortly after fertilization is facilitated by constitutive hypomethylation in the promoter region of this gene throughout spermatogenesis.
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Affiliation(s)
- J R McCarrey
- Department of Genetics, Southwest Foundation for Biomedical Research, San Antonio, Texas 78248
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32
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Smith A, Benavente R. Meiosis-specific protein selectively associated with sex chromosomes of rat pachytene spermatocytes. Proc Natl Acad Sci U S A 1992; 89:6938-42. [PMID: 1495983 PMCID: PMC49620 DOI: 10.1073/pnas.89.15.6938] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
During the first meiotic prophase of mammalian spermatogenesis, the sex chromosomes X and Y show a characteristic allocyclic behavior with respect to the autosomes. This is particularly evident during pachytene stage when sex chromosomes form the so-called sex vesicle. This structure is characterized by the condensed state of chromatin, transcriptional inactivity, and the limited extension of chromosome pairing, which is usually restricted to a short segment of sex chromosome axial elements. The molecular basis and functional significance of sex vesicle formation during mammalian spermatogenesis remain obscure. Here we report on the identification of a meiosis-specific sex vesicle protein we called XY40. Immunocytochemical localization on rat testis cryosections with a XY40-specific monoclonal antibody revealed that the labeling is confined to the axial elements of sex chromosomes. Biochemical characterization showed that protein XY40 (40 kDa; pI 5.7-5.8) can be extracted from rat pachytene spermatocytes and recovered in particles of 9.5 S with a native molecular mass of approximately 152 kDa. We speculate that protein XY40 may be involved in the allocyclic behavior of sex chromosomes during male meiotic prophase.
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Affiliation(s)
- A Smith
- Department of Zoology I, University of Würzburg, Federal Republic of Germany
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33
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Nayernia K, Burkhardt E, Beimesche S, Keime S, Engel W. Germ cell-specific expression of a proacrosin-CAT fusion gene in transgenic mouse testis. Mol Reprod Dev 1992; 31:241-8. [PMID: 1571157 DOI: 10.1002/mrd.1080310403] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Acrosin is a serine proteinase located in a zymogen form, proacrosin in the acrosome of the sperm. It is released as a consequence of the acrosome reaction and is believed to be the most important enzyme in the fertilization process. In the mouse, the proacrosin gene is transcribed premeiotically in spermatocytes, but protein biosynthesis starts in haploid spermatids and is restricted to the emerging acrosome. Four lines of transgenic mice harboring 2.3 kb of 5' untranslated region of the rat proacrosin gene fused to the CAT-reporter gene were generated by microinjection of fertilized eggs. The chimeric gene was found to be present in 10-100 copies per genome in the different strains. The 5' untranslated region of rat proacrosin gene could properly direct CAT-gene expression to spermatocytes and CAT-mRNA translation to round spermatids as it is known for mouse proacrosin gene. However, CAT protein is not restricted to the acrosome; rather, it is distributed in the spermatid cytoplasm. This could be due to the lack of DNA sequences for a hydrophobic leader peptide that have been found in all mammalian proacrosins studied until now but that was not present in transgene. It can be concluded from our results that cis-acting sequences required for tissue specific proacrosin expression reside on a 2.3-kb restriction fragment and are conserved in the proacrosin genes of mouse and rat.
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Affiliation(s)
- K Nayernia
- Institut für Humangenetik der Universität, Göttingen, Federal Republic of Germany
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34
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Mizunuma M, Dohmae K, Tajima Y, Koshimizu U, Watanabe D, Nishimune Y. Loss of sperm in juvenile spermatogonial depletion (jsd) mutant mice is ascribed to a defect of intratubular environment to support germ cell differentiation. J Cell Physiol 1992; 150:188-93. [PMID: 1346141 DOI: 10.1002/jcp.1041500125] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
C57BL/6(B6)-jsd/jsd mice are sterile due to the defective spermatogenesis in the testes. To know the cause of the deficient spermatogenesis in B6-jsd/jsd mice, we examined whether the problem is within or outside the seminiferous tubules by transplanting tubules from cryptorchid testes of B6- +/+ mice into B6-jsd/jsd testes or tubules from B6-jsd/jsd mice into testes of (WB x C57BL/6)F1-W/Wv (hereafter, WBB6F1-W/Wv) mice. Type A spermatogonia differentiated into spermatids in seminiferous tubules from cryptorchid testes transplanted into B6-jsd/jsd testes. In contrast, in B6-jsd/jsd tubules transplanted into WBB6F1-W/Wv testes, type A spermatogonia were stimulated to mitotic proliferation, but didn't proceed to any differentiated germ cells. The present results suggest that the cause of the deficient spermatogenesis in B6-jsd/jsd mice is a defect of intratubular environment to support germ cell differentiation.
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Affiliation(s)
- M Mizunuma
- Research Institute for Microbial Diseases, Osaka University, Japan
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35
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Abstract
Spermatogenesis is very similar throughout the animal kingdom and is probably based on very old evolutionarily principles. Drosophila can serve as a suitable model system to understand the underlying processes. The molecular and ultrastructural data obtained for Drosophila germ cell development can be applied to understanding spermatogenesis in other organisms, including humans. Various methods used in studies of Drosophila spermatogenesis are presented together with observations which exemplify this conclusion.
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Affiliation(s)
- W Hennig
- Department of Molecular and Developmental Genetics, University of Nijmegen, The Netherlands
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36
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Handel MA, Hunt PA, Kot MC, Park C, Shannon M. Role of sex chromosomes in the control of male germ-cell differentiation. Ann N Y Acad Sci 1991; 637:64-73. [PMID: 1785791 DOI: 10.1111/j.1749-6632.1991.tb27301.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- M A Handel
- Department of Zoology, University of Tennessee, Knoxville 37996
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37
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Eddy EM, O'Brien DA, Fenderson BA, Welch JE. Intermediate filament--like proteins in the fibrous sheath of the mouse sperm flagellum. Ann N Y Acad Sci 1991; 637:224-39. [PMID: 1723852 DOI: 10.1111/j.1749-6632.1991.tb27312.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- E M Eddy
- Gamete Biology Section, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709
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38
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Magram J, Bishop JM. Dominant male sterility in mice caused by insertion of a transgene. Proc Natl Acad Sci U S A 1991; 88:10327-31. [PMID: 1946451 PMCID: PMC52921 DOI: 10.1073/pnas.88.22.10327] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
While examining a series of transgenic mouse lines carrying the HCK protooncogene, we encountered one line in which males hemizygous for the transgene were sterile. The sterile males mated normally but failed to impregnate females. Light and electron microscopy revealed that spermatogenesis proceeds normally until nuclear condensation, which occurs but gives rise to a variety of abnormally shaped nuclei. Expression of the transgene was not detectable. Thus, the insertion itself probably caused the abnormal phenotype by disrupting a gene (or genes) important in spermatogenesis. The mutation is genetically dominant, causing an abnormal phenotype even though the sterile mice carry an ostensibly normal counterpart of the disrupted locus. The mutant phenotype is completely penetrant only in some genetic backgrounds, suggesting a modifying influence from a second locus. Junctions between the inserted transgene and adjoining cellular DNA were cloned, allowing us to confirm the heterozygous nature of the genetic disruption and to detect and associated deletion. We have designated the mutation Lvs (lacking vigorous sperm) and presume that it may define a previously undescribed locus important in spermatogenesis.
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Affiliation(s)
- J Magram
- G. W. Hooper Foundation, University of California, San Francisco 94143-0552
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39
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Searle AG, Whitehill KJ. Spermatogenic effects of male-fertile translocations in the mouse. Mutat Res 1991; 249:331-7. [PMID: 2072976 DOI: 10.1016/0027-5107(91)90008-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Four male-fertile translocations, T(2;4)13H, T(2.8)26H, T(7;18)50H and T(1;13)70H were crossed to the inbred strains CBA/H and C57BL/6J. F1 heterozygotes were compared with wild-type litter-mates for signs of spermatogenic impairment, in view of previous reports that the C57BL strain had this effect in the T(14;15)6Ca translocation. There was a general tendency for body-weights to be slightly reduced in translocation carriers vs. wild-type. Mean testis weights were significantly reduced on the C57BL background with all four translocations as compared to wild-type, but also significantly increased in T26H on CBA. Sperm counts were also reduced on the C57BL background in T13H, T50H and T70H (significantly so in the last two) but were significantly increased in T13H on a CBA background. Only in T50H did the frequency of sperm-head abnormalities show any marked change in the translocation heterozygotes, being approximately doubled with both CBA and C57BL backgrounds although still remaining at a low level. It was concluded that the deleterious effects of C57BL strains on spermatogenesis in translocation heterozygotes were not confined to T6Ca but were probably widespread. Some inconclusive evidence suggested that this might be because some genetic factors associated with C57BL tended to reduce chiasma frequencies in translocation heterozygotes.
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Affiliation(s)
- A G Searle
- MRC Radiobiology Unit, Chilton, Didcot, Oxon, Great Britain
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40
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Merlino GT, Stahle C, Jhappan C, Linton R, Mahon KA, Willingham MC. Inactivation of a sperm motility gene by insertion of an epidermal growth factor receptor transgene whose product is overexpressed and compartmentalized during spermatogenesis. Genes Dev 1991; 5:1395-406. [PMID: 1714416 DOI: 10.1101/gad.5.8.1395] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Transgenic mice were generated with a human epidermal growth factor (EGF) receptor cDNA driven by the chicken beta-actin gene promoter. One line (AE24) that exhibited a unique expression pattern in which dramatically elevated levels of EGF receptor RNA were found only in the testis was established, suggesting that the beta-actin promoter was being influenced by an adjacent testis-specific enhancer. EGF receptor RNA was detected in primary spermatocytes, whereas the synthesis of receptor protein was restricted to elongate spermatids, indicating that transgene expression was under translational control. At spermiation, the EGF receptor was sequestered in residual bodies and excluded from mature sperm by a compartmentalization mechanism. About half of AE24 homozygous males were sterile because of sperm paralysis, whereas heterozygous males and females of either genotype were completely fertile. Electron microscopic analysis of sperm flagella from sterile AE24 homozygotes revealed an aberrant axonemal structure in which outer doublet microtubules were missing from the middle piece, resembling changes observed in the sperm of some infertile humans. Flagellar axonemal disassembly was observed in the vas deferens and epididymis but not in the testis, suggesting that outer doublets were assembled in a grossly normal manner but possessed a latent instability. These results demonstrate that in the AE24 mouse line the EGF receptor transgene was integrated into and inactivated an endogenous autosomal gene, causing sperm flagellar axonemal disruption and male sterility.
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Affiliation(s)
- G T Merlino
- Laboratory of Molecular Biology, National Cancer Institute, Bethesda, Maryland 20892
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41
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Jassim A. AJ-p97: a novel antigen of the human sperm tail fibrous sheath detected by a neurofilament monoclonal antibody. J Reprod Immunol 1991; 20:15-26. [PMID: 1875327 DOI: 10.1016/0165-0378(91)90020-q] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Using indirect immunofluorescence (IIF), the RT97 anti-neurofilament monoclonal antibody (MoAb) detected an intracellular antigen in the principal piece of human ejaculated sperm tails. Its localisation to the tail fibrous sheath (FS) was confirmed by immunoelectron microscopy (IEM), which showed the binding of the gold particles to the outer FS surface. During spermatogenesis the antigen was first expressed on the spermatid FS, and its expression was continued on ejaculated mature sperm. In Western blotting of sperm lysates, the RT97 reacted with a 97 kDa protein (AJ-p97) which lacked disulphide bonds. This antigen was not detected on mouse or rat sperm tail FS, suggesting a sequence divergence of the AJ-p97 during evolution. The significance of these results and the relationship of AJ-p97 to neurofilaments are discussed, together with the use of the antibody as a probe for the structural dissection of the FS and for analysing the molecular events that take place during spermiogenesis, especially those involved in sperm tail morphogenesis.
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Affiliation(s)
- A Jassim
- Department of Immunology, London Hospital Medical College, U.K
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42
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Caldwell KA, Handel MA. Protamine transcript sharing among postmeiotic spermatids. Proc Natl Acad Sci U S A 1991; 88:2407-11. [PMID: 2006178 PMCID: PMC51241 DOI: 10.1073/pnas.88.6.2407] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Sharing of cytoplasmic constituents through intercellular bridges connecting postmeiotic spermatids can allow for functional equivalence of genetically nonequivalent spermatids. The technique of in situ hybridization was used to study postmeiotic distribution of transcripts from the mouse protamine 1 (Prm-1) gene among spermatids of mice with chromosomally unbalanced gametes. The Prm-1 gene is located on chromosome 16 and is expressed exclusively in haploid spermatids. Mice doubly heterozygous for two Robertsonian translocations involving chromosome 16 were used for the study of postmeiotic accumulation of transcripts of the Prm-1 gene in spermatogenic cells. The meiotic segregation pattern of chromosomal homologues in these mice produces some spermatids that are chromosomally unbalanced; some spermatids lack chromosome 16 while others have two. In situ hybridization with a cDNA probe for the Prm-1 gene transcript performed on both whole testis sections and spermatogenic cell suspensions showed that there was no statistical difference in distribution of grains over step-5 to step-10 spermatids from Robertsonian-translocation heterozygous mice and from control mice of normal karyotype. These results are consistent with sharing of transcripts of the Prm-1 gene among spermatids within a syncytium.
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Affiliation(s)
- K A Caldwell
- Department of Zoology, University of Tennessee, Knoxville 37996
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Ha H, Howard CA, Yeom YI, Abe K, Uehara H, Artzt K, Bennett D. Several testis-expressed genes in the mouse t-complex have expression differences between wild-type and t-mutant mice. DEVELOPMENTAL GENETICS 1991; 12:318-32. [PMID: 1718647 DOI: 10.1002/dvg.1020120409] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The t-complex of the mouse occupies the proximal half of chromosome 17 and contains genes which have profound effects on spermatogenesis. Mutations of several loci in the t-complex appear to interact to cause male sterility or transmission ratio distortion (TRD). By cDNA screening or chromosomal walking we have identified seven genes, which are expressed in the germ cells of testis and map to various regions of the t-complex. These genes were named t-complex testis-expressed (Tctex) genes. An analysis of their expression patterns in testes from +/+, +/t, and t/t mice was done by in situ hybridization and by northern blotting. Six genes begin to be expressed at the pachytene stage: Three of them are more abundant at pachytene stage, while three others are more abundant at postmeiotic stages. One gene is expressed at all the stages of spermatogenesis. Interestingly, four Tctex genes show differences in the amount of transcript between wild-type and t-mutant testes. The chromosomal location and expression pattern imply that Tctex genes might be candidate genes for sterility or TRD.
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Affiliation(s)
- H Ha
- Department of Zoology, University of Texas, Austin 78712-1064
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MacGregor GR, Russell LD, Van Beek ME, Hanten GR, Kovac MJ, Kozak CA, Meistrich ML, Overbeek PA. Symplastic spermatids (sys): a recessive insertional mutation in mice causing a defect in spermatogenesis. Proc Natl Acad Sci U S A 1990; 87:5016-20. [PMID: 2164218 PMCID: PMC54252 DOI: 10.1073/pnas.87.13.5016] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A line of transgenic mice that carries an insertional mutation in a gene essential for spermatogenesis is described. Males homozygous for the transgenic insert are sterile, while female homozygotes and both male and female heterozygotes exhibit normal fertility. Developing spermatids in homozygous males form prominent abnormal multinucleated syncytia (symplasts) and do not complete maturation. In addition, abnormal cytoplasmic vacuolation is commonly seen in Sertoli cells. One flank of the transgenic integration site within the genome has been cloned and used to show linkage between homozygosity for the transgene and the mutant phenotype. The flank maps to mouse chromosome 14 approximately 4 centimorgans proximal to the gene encoding esterase-10 (Es-10). As no other gene that is known to be essential for spermatogenesis has been mapped to this region of the genome and as the mutant phenotype is unique, the transgenic insert appears to affect a previously unidentified gene. We have named the mutation "symplastic spermatids" (sys).
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Affiliation(s)
- G R MacGregor
- Department of Cell Biology, Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030
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Robinson MO, McCarrey JR, Simon MI. Transcriptional regulatory regions of testis-specific PGK2 defined in transgenic mice. Proc Natl Acad Sci U S A 1989; 86:8437-41. [PMID: 2813402 PMCID: PMC298297 DOI: 10.1073/pnas.86.21.8437] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The gene encoding testis-specific phosphoglycerate kinase 2 (PGK; ATP:3-phospho-D-glycerate 1-phosphotransferase, EC 2.7.2.3) is expressed only in meiotic and haploid male germ cells. Transgenic mice containing an 8-kilobase human genomic PGK2 gene express the human gene in a tissue-specific and developmentally regulated manner. To determine the nature and location of sequences controlling this expression, transgenic mice with various lengths of the human PGK2 5' region fused to the chloramphenicol acetyltransferase (CAT) gene were analyzed for expression. A 323-base-pair region 5' to the coding region was found to contain information essential for both tissue-specific and developmentally regulated expression of the CAT reporter gene. Transgenic mice containing a PGK2/luciferase-coding construct were compared with mice containing an equivalent CAT construct. Luciferase gene expression was also testis-specific and was more sensitive than CAT gene expression, but otherwise regulation of the two reporter genes was similar in the germ cells of transgenic mice. Translation of both PGK2/CAT and PGK2/luciferase fusion genes was seen concurrently with the first detectable transcripts.
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Affiliation(s)
- M O Robinson
- Division of Biology, California Institute of Technology, Pasadena 91125
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Handel MA, Lane PW, Schroeder AC, Davisson MT. New mutation causing sterility in the mouse. GAMETE RESEARCH 1988; 21:409-23. [PMID: 3220432 DOI: 10.1002/mrd.1120210409] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A new murine mutation, skeletal fusions with sterility, sks, has been identified. This mutation causes arrest during the pachytene stage of virtually all spermatogenic cells. Defects in chromosome pairing and appearance of the synaptonemal complex during meiosis in the male are apparent, but defective pairing is probably not the cause of sterility. Affected females are functionally infertile. Oocytes are capable of undergoing meiotic maturation in vitro but cannot be fertilized in vitro. Affected individuals of both sexes are characterized by fusions of vertebrae and of ribs. The sks gene has been mapped to Chromosome 4, 16.6 cM distal to the brown locus.
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