Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “testis development”

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 1,585 records · Page 88Linked to original sources
PubMed2002

RNA binding protein Musashi1 is expressed in sertoli cells in the rat testis from fetal life to adulthood.

The Musashi1 (Msi1) gene identified in mouse is a member of a subfamily of RNA binding proteins that are highly conserved across species. Msi1 expression is highly enriched in proliferative cells within the developing central nervous system. Within the testis, proliferation and differentiation of germ cells takes place within the seminiferous epithelium, where these cells are supported physically and functionally by Sertoli cells that do not themselves proliferate following the onset of puberty. RNA binding proteins expressed in testicular germ cells are essential for normal fertility. Preliminary data suggested the mRNA for Msi1 was present in ovary; therefore, we used an Msi1-specific cRNA and monoclonal antibody to investigate whether Msi1 was expressed in the testis. Msi1 mRNA was expressed in rat testis from birth until adulthood; in situ hybridization revealed silver grains within the seminiferous epithelium. Immunohistochemical studies demonstrated that at all ages examined (from Fetal Day 14.5 until adulthood) Msi1 protein was expressed in Sertoli cells. In fetal and adult rat ovaries, Msi1 was detected in granulosa cells and their precursors. In Sertoli cells, protein was detected in both cytoplasmic and nuclear compartments; in adult testes, the immunointensity of the nuclear staining was stage dependent, with highest levels of expression in Sertoli cells at stages I-VI. In rat gonads, the RNA binding protein Msi1 is expressed in both proliferating and nonproliferating Sertoli and granulosa cells.

Aging↗
PubMed1996

[Familial occurrence of tumors and developmental anomalies of the testis].

BACKGROUND: Family occurrence ranks belong the factors followed in etiology and pathogenesis of germ-cell tumours of the testis. Its association with abnormal testicular development, respectively with other risk factors is relatively frequent. OBJECTIVES: The aim of this study was to indicate this coherence by means of case histories of author's patients and to propose further procedures. METHODS AND RESULTS: There were 535 patients treated for testicular cancer in the period of 1982-1994. Family occurrence was observed in 6 cases (1.12%), most frequently incombination with maldescensus testis. Individual families were analysed in detail, including HLA typization. Bilaterality of testicular cancer was observed in two brothers who were HLA identical. Other two brothers had the history of bilateral maldescensus testis, one of whom was subdued to bilateral orchiectomy in childhood, the other at the age of 16, a tumour in one testicle following orchidopexy performed in childhood. The history of maldesensus testis was observed in four members of another family, two of whom developed tumours. CONCLUSIONS AND MEANING FOR PRACTICE: Authors recommend supplementation of the initial examination of each patient with suspective testicular cancer with detailed family history aim at the occurrence of urogenital anomalies and tumours. General knowledge of the first-degree relatives about the possibility of family occurrence of tumours, and instructions for testicular self-examination are considered as the most suitable method from the stand point of secondary prevention. (Ref. 21.)

Adolescent↗
PubMed2000

The region on 9p associated with 46,XY sex reversal contains several transcripts expressed in the urogenital system and a novel doublesex-related domain.

Deletions of 9p have been associated with 46,XY gonadal dysgenesis, and the smallest region of overlap has been mapped to the tip of chromosome 9. Two candidate genes (DMRT1 and 2) have been found in the region. Despite intensive mutation searches, no mutations have been detected in these genes. To gain insights into the genomics of the region and to isolate other candidate genes for the phenotype, we have constructed a P1 artificial chromosome (PAC)/bacterial artificial chromosome (BAC) contig spanning over 500 kb and covering the consensus critical region. We have analyzed the expression pattern of several ESTs mapped or sublocalized within the framework of the contig. In addition, a sample shotgun sequencing of a PAC containing the mentioned DM genes led to the detection of novel transcripts displaying an expression pattern specific to testis and kidney, consistent with a role in the development of the urogenital system. One of them, expressed in adult testis and human embryos aged 4-5 weeks, encodes a potential polypeptide and is located immediately downstream of a sequence capable of encoding a novel DM domain. The region was partially screened for mutations in sex-reversed patients by Southern blot, sequencing, and FISH. No mutations were found. Our results suggest that the critical region on 9p involved in male-to-female sex reversal displays greater gene density and genomic complexity than previously anticipated. Future investigations will include functional and mutational studies of the novel transcripts mapped or sublocalized within the critical region by this study as well as cloning efforts to isolate additional candidate genes.

Adult↗
PubMed2000

Fhx (Foxj2) expression is activated during spermatogenesis and very early in embryonic development.

FHX (FOXJ2) is a recently characterized human fork head transcriptional activator that binds DNA with a dual sequence specificity. We have cloned the cDNA for the mouse orthologue Foxj2 and characterized its expression in the gonads and along the early pre-implantation development of the mouse. In the testis, Foxj2 is expressed from pachytene spermatocytes to round spermatids, but not in spermatogonia. In addition to the germ lineage, only Sertoli cells of the testis showed expression of Foxj2. In the ovary, only granulosa cells of the follicles express the factor. Neither mature spermatozoa nor oocytes showed expression of Foxj2. Foxj2 expression is early activated in zygotic development, being detected since as early as 8-cell stage embryos. Both cell layers of the blastocyst: the trophectoderm (TE) and the inner cell mass (ICM), express Foxj2.

Amino Acid Sequence↗
PubMed1976

Seasonal variation in the episodic secretion of luteinizing hormone and testosterone in the ram.

Rams of an ancient breed of domestic sheep (Soay) were housed under artificial lighting conditions to study the way in which the secretion of LH and testosterone changes in relation to the mating season. Conspicuous changes were found in the short-term fluctuations in plasma LH concentrations related to the cycle of testis growth and regression; serial blood samples collected at short intervals revealed episodic peaks in plasma LH at all times, but there were changes in the frequency (lowest when the testes were regressed and highest when fully active), amplitude (lowest at the peak of testis activity, and highest during the developing phase), and duration of the peaks (shortest when the testes were regressed). In addition, the basal levels changed from being lowest in the regressed phase of the testis cycle, and highest when the gonads were most active. Plasma testosterone concentrations changed in parallel with the cycle of testis size and were correlated with the fluctuating levels of LH. Each episodic peak in plasma LH was associated with an increase in the levels of testosterone, beginning after 0-30 min and rising to a peak at 60-90 min; the speed and magnitude of the response being greatest when the testes were largest, but was not correlated with the magnitude of the LH change. Injections of LH releasing hormone (5 mug) stimulated an increase in plasma LH and testosterone proportional to the endogenous fluctuations in the hormones at the various stages of the seasonal cycle; LH concentrations were raised to supra-physiological levels after the injections, while testosterone concentrations seldom exceeded the normal peak values at any stage. These observations are used to discuss the role of the hypothalamus in the control of male seasonality with emphasis on the dynamic interplay between the hypothalamus, pituitary and testis.

Animals↗
PubMed1977

On the nurse cell and the spermatozeugma in Littorina sitkana.

Nurse cells develop from diploid cells in the testis. Each cell undergoes a reduction division which leaves the nucleus with half the volume of a normal diploid cell. They send out pseudopodia which form desmosome-like junctions with developing spermatids. The nurse cells detach from the testicular wall, their nuclei degenerate and secretion droplets form in the cytoplasm. The pseudopodia are drawn in as the cytoplasmic secretions swell and the nurse cell becomes spherical. The eupyrene sperm become grouped unilaterally and at this stage are attached to the nurse cell by only the tips of their acrosomes. At maturity the nurse cells with their clumps of attached eupyrene sperm (spermatozeugmata) are released from the testis via ducts into the seminal vesicles,where they are stored prior to copulation. Nurse cells serve similar functions to those of apyrene sperm which are common among the Molluscs. We believe that the nurse cell and apyrene sperm are homologous.

Acrosome↗
PubMed1976

Experience in staging testis tumors with bleomycin 57cobalt and present role of 67gallium scan.

A technique was developed using bleomycin and 57cobalt to study nodal metastases in testis tumors. Comparative studies were made on 15 cases with 67gallium, lymphangiography, supraclavicular node biopsy, liver and spleen scans, chest x-ray, excretory urogram, bone survey and pathological study of surgical specimens when possible. The results with the bleomycin-57cobalt complex and 67gallium were discouraging. The bleomycin-57cobalt study was discontinued. Pathological staging is still the most accurate of all modalities available for staging testicular malignancies.

Biopsy↗
PubMed1994

A dosage sensitive locus at chromosome Xp21 is involved in male to female sex reversal.

Male to female sex reversal has been observed in individuals with duplications of the short arm of the X chromosome. Here we demonstrate that sex reversal results from the presence of two active copies of an Xp locus rather than from its rearrangement and that alterations at this locus constitute one of the causes of sex reversal in individuals with a normal 46,XY karyotype. We have named this locus DSS (Dosage Sensitive Sex reversal) and localized it to a 160 kilobase region of chromosome Xp21, adjacent to the adrenal hypoplasia congenita locus. The identification of male individuals deleted for DSS suggests that this locus is not required for testis differentiation. We propose that DSS has a role in ovarian development and/or functions as a link between ovary and testis formation.

Chromosome Mapping↗
PubMed2002

Novel expression and functional role of ghrelin in rat testis.

Ghrelin, the endogenous ligand for the GH-secretagogue receptor (GHS-R), is a recently cloned peptide, primarily expressed in the stomach and hypothalamus, that acts at central levels to elicit GH release and, notably, to regulate food intake. However, the possibility of additional, as yet unknown, peripheral effects of ghrelin cannot be ruled out. In the present communication, we provide evidence for the novel expression of ghrelin and its functional receptor in rat testis. Testicular ghrelin gene expression was demonstrated throughout postnatal development, and ghrelin protein was detected in Leydig cells from adult testis specimens. Accordingly, ghrelin mRNA signal became undetectable in rat testis following selective Leydig cell elimination. In addition, testicular expression of the gene encoding the cognate ghrelin receptor was observed from the infantile period to adulthood, with the GHS-R mRNA being persistently expressed after selective withdrawal of mature Leydig cells. From a functional standpoint, ghrelin, in a dose-dependent manner, induced an average 30% inhibition of human CG- and cAMP-stimulated T secretion in vitro. This inhibitory effect was associated with significant decreases in human CG-stimulated expression levels of the mRNAs encoding steroid acute regulatory protein, and P450 cholesterol side-chain cleavage, 3beta-hydroxy steroid dehydrogenase, and 17beta-hydroxy steroid dehydrogenase type III enzymes. Overall, our data are the first to provide evidence for a possible direct action of ghrelin in the control of testicular function. Furthermore, the present results underscore an unexpected role of ghrelin as signal with ability to potentially modulate not only growth and body weight homeostasis but also reproductive function, a phenomenon also demonstrated recently for the adipocyte-derived hormone, leptin.

Animals↗
PubMed2002

Functional analysis of the transcription factor ER71 and its activation of the matrix metalloproteinase-1 promoter.

The ETS transcription factor family is characterized by a conserved ETS DNA-binding domain and its members have been implicated in a plethora of biological processes, including development, cell transformation and metastasis. ER71 is a testis-specific ETS protein that is not homologous to any other protein outside its ETS domain, suggesting that it fulfills a unique physiological role. Here, we report that ER71 is a constitutively nuclear protein whose intracellular localization is dependent on a portion of the ETS domain, namely ER71 amino acids 276-315. Furthermore, the DNA binding activity is intramolecularly regulated, as the N-terminus of ER71 has a negative effect on DNA binding while the C-terminus dramatically enhances this activity. We also demonstrate that ER71 possesses an extremely potent N-terminal transactivation domain comprised of amino acids 1-157. Finally, we show that ER71 is capable of directly activating both an E74 site-driven and the matrix metalloproteinase-1 promoter. Altogether, these data represent the first functional characterization of ER71, which may perform important functions in the developing and adult testis as well as in testicular germ cell tumorigenesis.

Animals↗
PubMed2004

[Establishment of animal model for in vitro spermatogenesis by heterotopic grafting of neonatal mouse testis].

OBJECTIVE: To establish an in vitro model for the development of mouse spermatogenic cells into sperm by using the immunodefective mouse as the incubator. METHODS: Tissue grafting was performed using testis from 1-2 days old Kun-ming mice as donor tissue and immunodefective mice as recipients; the expression of TESK1 mRNA in grafts was determined by RT-PCR and the spermatogenesis further observed with histological analysis of grafts. RESULTS: Molecular biological and histological analyses showed that grafts post-grafting not only expressed TESK1 mRNA as in normal mouse testis, but also exhibited similarities in the structure of seminiferous tubules and component of spermatogenic cells, including sperms. CONCLUSION: Spermatogenic cells heterotopically grafted in vitro could continuously grow and complete spermatogenesis and finally develop into sperm.

Animals↗
PubMed1981

Sertoli-Leydig cell tumors: a clinicopathologic study of 34 cases.

Thirty-four cases of Sertoli-Leydig cell tumor were studied. All tumors were limited to the ovary at the time of initial surgery. Eight tumors were well differentiated, 15 were of intermediate differentiation, and 11 were poorly differentiated. Six cases contained heterologous elements. The less differentiated tumors occurred in patients with a lower median age and were more likely to produce androgenic manifestations. Follow-up of one year or longer was obtained in 15 patients, with an average follow-up in these patients of 6.1 years. Only one patient, who had a poorly differentiated tumor, died of the neoplasm in this series. Although follow-up was limited in this study, our findings suggest that the better differentiated tumors have a relatively favorable prognosis. This neoplasm is composed of sex-cord and stromal elements, and its components have the capacity to a greater or lesser extent to recapitulate the cells of the testis at different stages of development.

Adolescent↗
PubMed1995

The origin and function of the mammalian Y chromosome and Y-borne genes--an evolving understanding.

Mammals have an XX:XY system of chromosomal sex determination in which a small heterochromatic Y controls male development. The Y contains the testis determining factor SRY, as well as several genes important in spermatogenesis. Comparative studies show that the Y was once homologous with the X, but has been progressively degraded, and now consists largely of repeated sequences as well as degraded copies of X linked genes. The small original X and Y have been enlarged by cycles of autosomal addition to one partner, recombination onto the other and continuing attrition of the compound Y. This addition-attrition hypothesis predicts that the pseudoautosomal region of the human X is merely the last relic of the latest addition. Genes (including SRY) on the conserved or added region of the Y evolved functions in male sex determination and differentiation distinct from the general functions of their X-linked partners. Although the gonadogenesis pathway is highly conserved in vertebrates, its control has probably changed radically and rapidly in vertebrate--even mammalian--evolution.

Animals↗
PubMed1988

Differential distribution of beta-tubulin isotypes in cerebellum.

We describe the structure and expression of a mammalian beta-tubulin isotype (M beta 6) that is weakly expressed in testis but is abundant in developing brain, with transcripts declining to lower levels in the adult brain. The expression of M beta 6 was undetectable in any other mouse tissue examined. A serum specific for this isotype was prepared using a cloned fusion protein as immunogen. M beta 6 is one of five known beta-tubulin isotypes expressed in brain, and using the anti-M beta 6 serum along with sera, anti-M beta 2, anti-M beta 3/4 and anti-M beta 5, previously characterized, we have examined the pattern of expression of beta-tubulin isotypes in rat cerebellum. The isotypes each have characteristic cell-type specific patterns of localization in cerebellum. M beta 2, M beta 3/4 and M beta 5 are present in both neuronal and non-neuronal cells, but in contrast M beta 6 was only detectable in neurons in tissue sections and in dissociated cerebellar cell culture. The majority of sequence differences among the beta-tubulin isotypes lie at the carboxy terminus, the region of beta-tubulin involved in MAP binding. In the case of M beta 2 and M beta 6, the patterns of expression are similar or identical to the patterns of expression of MAP3 and MAP1A respectively. These results suggest that beta-tubulin isotypes may contribute to the determination of the specific association of MAPs with microtubules of diverse function. However, the strict subcellular segregation of other MAPs in brain may be determined by other factors.

Amino Acid Sequence↗
PubMed1992

Comparative aspects of spermatogenic cell metabolism and Sertoli cell function in Xenopus laevis and mammals.

Due to the relative dearth of data regarding somatic cell-germ cell interactions in the testes of non-mammalian chordates, functional homologies between Sertoli cells from diverse organisms have been difficult to assess. However, recent developments in non-mammalian testis cell and organ culture techniques have provided experimental approaches to compare Sertoli cell-germ cell interactions in different vertebrates. Data from in vitro analyses of Sertoli cell-germ cell interactions are presented to suggest that Sertoli cells from rodents and the frog Xenopus laevis have similarities in supporting energy metabolism and glutathione metabolism in spermatogenic cells. Comparative in vitro analyses of Sertoli cell functions should provide further insights into the evolution of cell-cell interactions in the testes.

Animals↗
PubMed1993

Differential perinatal testosterone secretory capacity of wild house mice testes is related to aggressiveness in adulthood.

Testosterone secretory capacity of testicular Leydig cells was determined in fetal males of an aggressive and a nonaggressive genetic selection line of wild house mice. They were studied at Days 15-18 of gestation and on the first day after birth. A previously described morphometric method was used to quantify 3 beta-hydroxy steroid dehydrogenase (3 beta-HSD)-stained Leydig cells in testicular sections to determine testosterone secretory capacity, which may be considered to reflect circulating plasma testosterone in the fetus. The results of this study show that the testosterone secretory capacity of Leydig cells in the testis changes differentially during intrauterine development in males of the aggressive and nonaggressive selection lines. The peak secretory capacity is reached at Day 17 of gestation for the males of the aggressive selection line, while the peak for the nonaggressive males is reached on the first neonatal day. The larger anogenital distance observed in aggressive males suggests a higher prenatal testosterone level in these males. The importance of the difference in timing of the perinatal 3 beta-HSD peak top individual variation in adult aggressive behavior is discussed.

3-Hydroxysteroid Dehydrogenases↗
PubMed2004

Sperm membrane protein (hSMP-1) and RanBPM complex in the microtubule-organizing centre.

hSMP-1 is a human sperm membrane protein expressed during development. It is a testis-specific component produced during male germ cell differentiation. Proteins that interact with hSMP-1 were identified by the application of the yeast two-hybrid system. One of the components, RanBPM, was found to be associated with hSMP-1 under both in vitro and in vivo conditions. In the human testis, RanBPM is produced in spermatogonia and primary spermatocytes, suggesting expression during the early stages of spermatogenesis; whereas in the rat testis, it is located in round and elongated spermatids, similar to hSMP-1, suggesting expression of both components during spermiogenesis. Images obtained by immunofluorescence and confocal scanning microscopy of CHO-K1 cells co-transfected with pEGFP-C1-hSMP-1 and pDsRed1-Nl-RanBPM revealed that RanBPM and hSMP-1 are distributed in discrete loci throughout the cytoplasm. When superimposed, the stained spots appeared as congruent yellow areas, indicative of co-localization and probable complex formation of these two components. This interaction between hSMP-1 and RanBPM may be involved in the process of male germ cell differentiation. In CHO-Kl cells transfected with pEGFP-Cl-hSMP-1, the exogenously expressed hSMP-1 was found to co-localize with alpha-tubulin. Depolymerization of microtubules can be induced in CHO-Kl cells by cold treatment. In cells transfected with the pEGFP-Cl vector, the dispersed tubulins promptly reassembled upon warming. However, in cells transfected with pEGFP-Cl-hSMP-1, reassembly of the dispersed tubulins was blocked even upon rewarming of the cells. These findings suggest that hSMP-1 interacts with tubulins and thereby may modulate microtubule assembly and/or activity.

Adaptor Proteins, Signal Transducing↗