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Proteins encoded by p63 gene a have structural similarity with tumor suppressor p53, and were thought to induce cell cycle arrest and apoptosis during development. The p63 proteins are also expressed in the basal cells of many epithelial tissues in the adult, and supposed to play important roles in maintaining the epidermal stem cells. Previously, we reported the p63 expression in the testis of mouse embryos, suggesting their involvement in the growth arrest and apoptosis of testicular germ cells (Nakamuta and Kobayashi, J. Vet. Med. Sci. 65:853-856). In this study, we investigated the timing of this p63 expression in the germ cells during migration and colonization to the gonads. Immunohistochemical analysis of mice from embryonic day (E) 7.5 to E12.5 demonstrated that p63 positive reactivity was seen as early as E8.5 when the founder cells of germ cells, primordial germ cells (PGCs), were located in the hind gut epithelium, but PGCs were negative for p63 at E7.5 when they first appeared. p63 is expressed as six isoforms, resulting from alternative splicing at C-terminus and by the use of two promoters that generate variations at N-terminal end. RT-PCR analyses suggested that different types of p63 mRNAs were likely to be expressed in PGCs during development. These results imply that p63 may be involved in the regulation of PGC development by controlling the gene expression required for their migration and colonization to the gonads.  相似文献   

3.
The present study describes the morphological characteristics of black howler monkey (Alouatta caraya) ovarian follicles. One ovary of an adult healthy black howler monkey was collected and processed for light and electron microscopy. Primordial, primary, secondary, tertiary and pre-ovulatory follicles were evaluated for their morphometrical aspects. The ovary of black howler monkey presented a distinct conformation with a uniform distribution of the follicles mostly in the peripheric cortex. This black howler monkey ovary presented a total of 59 921 ovarian follicles. From this amount, 71.1% were classified as primordial, 18.9% as primary, 8.1% as secondary, 1.4% as tertiary and 0.5% as pre-ovulatory follicles. From all these developmental stages, the mean diameters of follicles, oocytes, oocytes nuclei and the mean number of granulosa cells are described. Moreover, primordial, primary and secondary follicles have been observed by electron microscopy.  相似文献   

4.
We previously identified a novel gonad-specific expression gene (Gse) and investigated its expression during gametogenesis in the mouse testis and ovary. In this study, we generated a polyclonal antibody to GSE protein and determined the profiles of the protein's expression in germ cells and preimplantation embryos in detail using immunocytochemical and immunofluorescence staining. In a Western blot analysis, the anti-GSE antibody recognized long and short isoforms (approximately 27.6 kDa and 23.1 kDa) of the protein in the mouse testis and the long isoform in the ovary. In the mouse testis, GSE protein was expressed in spermatocytes I in the pachytene stage, round spermatids, and elongated spermatids. In the mouse ovary, the protein was located in the cytoplasm and nucleus of all oocytes regardless of the stage of the ovarian follicles. In preimplantation embryos from the pronuclear to blastocyst stage, however, GSE protein was mainly detected in the nuclei of cells. At the blastocyst stage, the protein was confirmed to have accumulated in the inner cell mass (ICM), whereas it had mostly disappeared from the trophectoderm (TE). These findings suggest that GSE protein may play a role in the establishment of nuclear totipotency and may be associated with early lineage specification.  相似文献   

5.
Ovarian follicular development in mammals is the complex process including endocrine, paracrine and autocrine. There is the development of four basic stages of ovarian follicles, i.e. the primordial, primary, secondary and tertiary or Graafian follicles. There are few blood vessels in the cortical area where primordial and primary follicles are assembled. The development of these follicles is stimulated by oocytes derived factor including growth differentiation factor 9 (GDF-9) or bone morphogenetic protein 15 (BMP-15). Porcine GDF-9 complementary DNA (cDNA) cloned, and then injected its gene into the ovary in gilts. The injection of porcine GDF-9 gene resulted in an increase in the number of primary, secondary and tertiary follicles, concomitant with a decrease in the number of primordial follicles, indicating that exogenous GDF-9 can promote early folliculogenesis in the porcine ovary. On the other hand, the development of antral follicles is associated with increased density of blood vessels within the theca cell layers surrounding the follicles. A recent study reported that vascular endothelial growth factor (VEGF) play an important role in the process of thecal angiogenesis during follicular development. To investigate whether additional induction of thecal angiogenesis would support subsequent follicular development, miniature gilts were directly injected VEGF gene into the ovary. Injection of VEGF gene increased the levels of mRNA expression of VEGF 120 and VEGF 164 isoforms in the granulosa cells and VEGF protein contents in the follicular fluid. The number of preovulatory follicles and the capillary density in the theca interna increased significantly in the ovaries injected with VEGF gene compared with those treated with eCG alone, indicating that the regulation of thecal angiogenesis during follicular development is a very important factor in the development of ovulatory follicles. This technique may be an innovative technique for enhanced induction of follicular development in the ovary through gene and hormonal treatment, which may lead to prevention of infertility caused by ovarian dysfunction.  相似文献   

6.
In this study, buffalo AQP8 gene was cloned and its eukaryotic expression vector was constructed, the expression pattern of AQP8 gene in buffalo ovary tissue was also assayed. The results showed that the CDS length of cloned buffalo AQP8 gene was 732 bp, and it shared 100% homology of amino acid sequence with cattle and mouse. AQP8 protein was detected in different developmental stages of buffalo follicles, it had significantly higher expression in the secondary follicles than that of in the primordial and the primary follicles (P<0.05), and it mainly expressed in the granulosa cells of the secondary follicles. Clear EGFP green fluorescent was observed in transfected cell groups with transfection of the pEGFP-N1-AQP8 eukaryotic expression plasmid into HEK293T cells by LipofectamineR LTX and PLUSTM reagent. The above results lay foundation to further investigate the function of AQP8 gene in the buffalo follicle development and granulosa cell apopotosis.  相似文献   

7.
随着体外受精、克隆与转基因动物等基础研究快速发展,对卵母细胞的需求越来越多,科学家们不得不寻求能够获得大量优质卵母细胞的新途径。原始卵泡作为生长卵泡的来源,其初始容量影响哺乳动物的繁殖性能,是整个雌性生殖期中各阶段卵泡及卵子发育的源头。哺乳动物的卵巢在出生时由一定数量的卵泡组成,大多数原始卵泡处于休眠状态,只有极少数的原始卵泡被激活并进入生长卵泡池中。因此合理开发卵巢里尚未激活的原始卵泡对提高动物繁殖率、加速优良牛种的遗传改良、阐明动物卵泡发生的分子机理具有重要意义。本文将目前哺乳动物原始卵泡体外激活的国内外进展做一综述,为研究动物和人类卵泡激活的生物学过程提供理论基础。  相似文献   

8.
Vascular endothelial growth factor (VEGF) is an important angiogenic factor in the ovary, but the localization of VEGF in the ovary of neonatal animals is poorly understood. A clear understanding of the relationship between the formation of the thecal layer and the cell‐specific expression of the VEGF system during follicular development in the neonatal ovary is still lacking. Immature female Wistar‐Imamichi rats used in this study were killed by decapitation 5, 7, 9 and 11 days after birth, and their ovaries were removed and subjected to histological and immunohistochemical observation. The number of primordial follicles had decreased in the ovaries at day 11 compared with that at day 5. The number of secondary follicles significantly increased with age. In the morphological observation of secondary follicles, we found that the theca layer (70 µm in diameter of follicles) began to form at day 9 and was completely formed at day 11. An endothelial cell marker, CD31, VEGF and Flk‐1 were located in the stromal tissues in the ovaries on each day examined after birth. In particular, in the ovaries at day 9 and day 11, when the secondary follicles appeared, CD31, VEGF and Flk‐1 were expressed in the theca layer. Flt‐1 was expressed in the oocytes of the ovaries at day 5 and day 7, and the sites of its expression changed to stromal and thecal tissues at day 9 and day 11. In conclusion, we provide the first evidence that the theca layer of secondary follicles begin to form at day 9 after birth and that VEGF and Flk‐1 may be able to stimulate the differentiation of stromal‐interstitial cells into thecal cells and the formation of the thecal vasculature in the neonatal rat ovaries, suggesting that the VEGF system may be involved in the formation of the thecal layer and vasculature during folliculogenesis in the neonatal rat.  相似文献   

9.
The mammalian ovary contains a huge number of small follicles of various sizes, and each follicle encloses a small oocyte. Only a small number of non-growing oocytes (30 microm in the pig and cow) grow to their final size (120 microm), mature, and are ovulated. In vitro growth (IVG) culturing of small oocytes will provide a new source of mature oocytes for livestock production. Using the IVG culture system, non-growing mouse oocytes in primordial follicles grow to their final size and acquire full developmental competence. Among large animals, babies were produced from ovarian oocytes by IVG culture only in the cow. However, the oocytes used were not non-growing ones but at the mid-growth stage (90-99 microm in diameter) in early antral follicles. Xenotransplantation of the follicles at an early stage to immuno-deficient mice is a substitute for an effective long-term IVG culture of much smaller oocytes. IVG and xenotransplantation of small oocytes at a specific size will provide a new understanding of the mechanisms regulating oogenesis and folliculogenesis in the complex mammalian ovary.  相似文献   

10.
This study quantified Fibroblast growth factor 2 (FGF-2) mRNA and localized FGF-2 protein in different categories of follicles isolated from goat ovaries. In addition, we verified the effects of this factor on the in vitro culture of preantral follicles isolated from goats. For mRNA quantification, we performed real-time PCR using primordial, primary and secondary follicles, as well as cumulus-oocyte complexes (COCs) and mural granulosa and theca cells of small and large antral follicles. For FGF-2 protein localization, the ovaries were subjected to conventional immunohistochemical procedures. Preantral follicles were isolated and cultured in vitro for 12 days in either control (basic) or supplemented with FGF-2 medium. The expression of FGF-2 mRNA was detected in all categories of follicles and there was no difference in preantral follicles and COCs or granulosa/theca cells from small and large antral follicles. However, in large antral follicles, COCs showed expression levels significantly lower than in granulosa/theca cells (p < 0.05). We observed moderate expression of FGF-2 protein in preantral follicles but not in granulosa cells of primordial follicles and theca cells of secondary follicles. In both small and large antral follicles, strong, moderate and weak staining was observed in oocytes, granulosa and theca cells, respectively. The addition of FGF-2 caused a significant increase in the daily follicular growth rate compared to the control group. We conclude that FGF-2 mRNA is expressed throughout follicular development and that its protein can be found in different patterns in preantral and antral follicles. Furthermore, FGF-2 increases the follicular growth rate in vitro.  相似文献   

11.
The alphavbeta3 and alphavbeta5 integrins are known as transmembrane receptors capable of binding to the RGD amino acid peptide sequence. In mouse early gonadogenesis, some proteins containing the RGD sequence are deposited into extracellular space and participate in morphogenesis. We analyzed the expression patterns of the alphavbeta3 and alphavbeta5 integrins in mouse developing gonads (10.5-13.5 days post coitum) using whole-mount in situ hybridization. The alphav integrin mRNA was homogenously expressed in developing gonadal regions. On the other hand, the beta3 integrin mRNA was found only in large and round cells (presumptive germ cells), whereas beta5 integrin was localized in gonadal somatic cells, with the exception of coelomic epithelial cells. The beta3 integrin-expressed cells were determined to be primordial germ cells because the number of these cells was drastically reduced in busulfan-treated gonads. In this study, we demonstrated that the alphavbeta3 and alphavbeta5 integrins are widely localized in the mouse developing gonads and discussed their presumptive functions on mouse gonadogenesis.  相似文献   

12.
探讨Zhangfei(ZF)在动情周期小鼠子宫和卵巢中的分布规律.通过阴道涂片方法确定昆明雌性小鼠的动情周期,利用免疫组化SP法检测了ZF在小鼠动情周期子宫和卵巢组织中的定位.ZF在各级卵泡的卵母细胞中均呈阳性分布,且主要定位于胞质中;次级卵泡和三级卵泡的颗粒细胞层中可见ZF的存在;成熟卵泡的颗粒细胞中ZF蛋白的阳性更...  相似文献   

13.
The aim of this investigation was to study the ultrastructural features during the development of fetal bovine ovaries (crown rump length ranging from 11.4 to 94.0 cm). An interesting observation was the occurrence of big elongated cells containing a variety of electron dense granules and light homogenous vacuoles/bodies. They were located between the stroma cells surrounding the germ cell cord ends, adjacent to the first formed primordial follicles, typically situated near blood vessels. ER alpha and ER beta receptor positive cells could be detected in the same regions by means of immunohistochemistry. Intercellular bridges linked the germ cells nests oogonia. Germ cell cords consisted of centrally located, large, pale oogonia, surrounded by elongated somatic cells with very long cytoplasm extensions. Primordial follicles with flat pale follicular cells could be observed on the inner end of the cords. Extrusions of the outer nuclear membrane could often been recognised in voluminous oocytes.  相似文献   

14.
研究休情期银黑狐卵巢形态和卵泡的显微结构,以揭示银黑狐卵巢发育的一般规律。本试验于2012年12月份采集5只健康一岁龄银黑狐卵巢10枚,用游标卡尺测量其长、宽、厚,用电子天平测量其重量,并对其表面可见卵泡数量进行统计,然后利用光学显微镜对各级卵泡分别观察1~3个,共计原始卵泡30个,初级卵泡20个,次级卵泡15个,三级卵泡12个,成熟卵泡10个,并进行拍照。结果表明:随银黑狐卵巢体积不断增大,其中80%的卵巢重量也随之增大;可见卵泡数量与卵巢体积及重量没有相关性;卵巢由被膜、皮质和髓质构成,髓质位于卵巢内层,分布着较多血管,皮质位于卵巢外层,内有不同发育阶段的卵泡;原始卵泡由卵母细胞和颗粒细胞构成,初级卵泡开始出现透明带物质,到次级卵泡阶段发育完整,三级卵泡出现卵泡腔,卵泡及卵母细胞直径在有腔卵泡阶段比腔前卵泡阶段增长速度快,成熟卵泡的直径及透明带厚度达到最大,各级卵泡均有闭锁现象。  相似文献   

15.
In mice, small oocytes (primordial oocytes) are enclosed within flattened granulosa cells to form primordial follicles around birth. A small number of primordial oocytes enter the growth phase, whereas others are quiescent. The mechanism regulating this selection of primordial oocytes is not well understood. The objective of the present study was to understand the role of p27(Kip1), which regulates cell cycle progression in somatic cells, in the growth initiation of primordial oocytes in neonatal mice. We studied the localization of p27(Kip1) in 0-, 3-, 5-, 7- and 21-day-old mouse ovaries by immunohistochemistry. Ovaries from 3-day-old mice were treated with p27(Kip1) siRNAs (small interfering RNAs), and knockdown of p27(Kip1) was determined by immunohistochemistry and Western blotting. Ovaries treated with siRNAs were organ-cultured for 6 days, and oocyte growth was estimated histologically. Expression of p27(Kip1) was undetectable in the primordial oocytes of newborn mice. In the 3-day-old ovaries (n=3), p27(Kip1) was demonstrated in the nucleus of 36 ± 6% primordial oocytes. The percentage of p27(Kip1)-positive primordial oocytes increased to 72 ± 8 (n=3), 85 ± 7 (n=3) and 93 ± 5 (n=3) in the 5-, 7- and 21-day-old mouse ovaries, respectively. After knockdown of the p27(Kip1) protein by siRNAs, a higher proportion of oocytes entered the growth phase in cultured ovaries than those in the control. These results suggest that p27(Kip1) negatively regulates primordial oocyte growth and that knockdown of p27(Kip1) leads primordial oocytes to enter the growth phase in vitro.  相似文献   

16.
研究EGF mRNA在猪各级卵泡内的表达。采用RT-PCR技术检测猪大卵泡,中卵泡和小卵泡中,以及各级卵泡卵母细胞和颗粒细胞中EGF的mRNA的表达。结果表明大卵泡,中卵泡和小卵泡中都有EGF的mRNA表达,但看不出明显的强弱变化,卵母细胞和颗粒细胞中也有表达,且从小卵泡到中卵泡到大卵泡有明显减少的趋势,卵母细胞比颗粒细胞表达强烈。进一步证实EGF在猪卵泡及卵母细胞发育中起着重要作用。  相似文献   

17.
The cellular localization of nerve growth factor (NGF) and its receptors (TrkA, p75) was investigated during the estrous cycle in gilts. Also, the levels of expression of these factors in walls of tertiary follicles and corpora lutea (CLs) were determined using Western blot. The ovaries from days 3, 7, 16 and 20 of the cycle revealed the presence of NGF and its receptors in oocytes of secondary and tertiary follicles, follicular cells of primary and secondary follicles, thecal and granulosa cells of tertiary follicles and steroidogenic cells of CLs. In wall cells of primary follicles, NGF, TrkA and p75 staining was strongest on day 16, while in secondary follicles, only p75 was more intensely stained on day 16 and 20. In walls of small (to 3 mm in diameter) and medium (4-6 mm in diameter) follicles, NGF staining was lower on day 16, and the p75 reaction was strongest on day 20. On day 20, NGF staining in large follicles (7-10 mm in diameter) was higher than in smaller follicles. The levels of NGF and p75 in small and medium follicles were highest on day 20. The contents of NGF and TrkA in large follicles on day 20 were higher than in smaller follicles. NGF and TrkA contents in CLs were highest on day 7. Our study demonstrates that NGF, TrkA and p75 are expressed in the ovary during the estrous cycle in gilts. These results suggest that NGF and its receptors may be important for ovarian function in cycling gilts.  相似文献   

18.
This study was designed to reveal connexin 43 (Cx43) mRNA and protein expression in porcine foetal gonads using RT‐PCR, immunohistochemistry and Western blot analysis. Expression of Cx43 was investigated in porcine foetal ovaries and testes on days 50, 70 and 90 post coitum (p.c.). RT‐PCR results indicated that Cx43 mRNA was expressed in both foetal ovaries and testes at all gestational ages examined. Cx43 protein was found in the foetal ovary but its distribution varied across ovarian compartments and changed during development. In foetal ovaries, Cx43 was localized between the interstitial cells surrounding egg nests on all investigated days of prenatal period. Moreover, Cx43 expression was observed between germ cells on day 50 p.c. as well as between pre‐granulosa and granulosa cells of primordial and primary follicles on days 70 and 90 p.c. In the foetal testes, Cx43 protein was detected between neighbouring Leydig cells on all examined days of prenatal period and between adjacent Sertoli cells exclusively on day 90 p.c. The presence of Cx43 protein in all investigated foetal gonads was confirmed by Western blot analysis. Cx43 protein detection between pre‐granulosa cells of primordial follicles suggests its role in regulation of the initial stages of follicle development. The Cx43 immunoexpression between neighbouring Leydig and between Sertoli cells indicates its involvement in controlling their functions. We propose that Cx43‐mediated gap junctional communication is involved in the regulation of porcine foetal gonadal development.  相似文献   

19.
Summary Multipotent stem cells (source for interfollicular epidermis, hairs and sebaceous glands) are localized in the bulge region of the outer root sheath of hair follicles, while stem cells giving rise to interfollicular epidermis reside in its basal. Using the multifunctional lectin galectin-1 as a marker to localize accessible binding sites in situ as a step to figure out galectin functionality in stem cells, we studied hair follicle-derived keratinocytes. Specific nuclear binding of galectin-1 associated with expression of DeltaNp63alpha, a potential marker of epidermal stem cells, was detected. Binding of chimera-type galectin-3 to a nuclear site was not found in parallel assays. During the process of ageing in culture when cells acquire properties of senescence, disappearance of the nuclear signal for galectin-1 binding was accompanied by a similar decrease of nuclear DeltaNp63alpha expression and increased binding of galectin-3 to the cell membrane, namely in regions of intercellular contacts. Expression of cytokeratin 10, a marker of the terminal differentiation was seen only in a small fraction of the cell population. These data extend the evidence for nuclear sites with galectin-1 reactivity in squamous epithelial cells, the expression of which is modulated upon senescence. Moreover, the results document the divergence of galectin-1 and -3 on the level of ligand selection in this cell type, underscoring the importance of the technical aspect to employ tissue lectins as probe and to perform a fingerprinting with several markers of the galectin family in parallel.  相似文献   

20.
The objective of the present study was to elucidate the involvement of FOXO3 in the activation of bovine primordial follicles. In immunohistochemistry, FOXO3 was detected in all of the oocytes in primordial and primary follicles. The FOXO3 decreased after treatment with FOXO3 small interfering RNAs (siRNAs). Ovarian tissues containing dominantly primordial follicles were treated with FOXO3 siRNAs and then xenografted to severe combined immune deficiency (SCID) mice. Two months after xenografting, some primordial follicles developed to the secondary and tertiary stages, and the total percentage of these developing follicles (secondary and tertiary follicles: 18 ± 7%) was higher than in the control grafts treated with control siRNA (7 ± 1%). It is thought that bovine primordial follicle activation is regulated by the FOXO3-dependent mechanism and that knockdown of FOXO3 induces the release of primordial follicles from FOXO3 suppression, initiating their growth.  相似文献   

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