共查询到20条相似文献,搜索用时 15 毫秒
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Karl-Ove Sderstrm 《Experimental cell research》1981,131(2)
In this study it is shown that a cytoplasmic cell organelle, the chromatoid body, becomes labelled with [3H]uridine in the pachytene spermatocytes. The chromatoid body becomes labelled when the cells are first labelled for 2 h in the presence of [3H]uridine and thereafter chased for 9 h in the presence of unlabelled uridine. This labelling is inhibited by the specific RNA polymerase II inhibitor α-amanitin. Based on this it is suggested that part of the RNA synthesized in the pachytene spermatocytes is stored in the chromatoid body and transported to the postmeiotic spermatids where it is used in the differentiation of the spermatids. 相似文献
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Summary During spermatogenesis in Gerris remigis, chromatoid bodies appear in the spermatocytes and persist to the-mid-spermatid stage. These structures consist of numerous, parallel tubules, which measure approximately 500 Å in diameter. The tubules are arranged in hexagonal array, and contain dense granules that resemble ribosomes. The chromatoid body may be secretory in function, or may be involved in intracellular transport.The technical assistance of Mr. Roy R. Keppie and Mrs. Mona Brandreth is gratefully acknowledged. 相似文献
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Karl-Ove Söderström 《Cell and tissue research》1981,215(2):425-430
Summary Cytoplasmic structures ultrastructurally similar to the nuage are present in the cytoplasm of all spermatogenic cells in adult rats. The nuage is a discrete organelle which should not be confused with the chromatoid body. In step 7–8 spermatids transient contact is established between the nuage and the chromatoid body. This indicates a very specific recognition of the nuage by the chromatoid body. It is suggested that the nuage and the chromatoid body are separate cell organelles the functions of which are somehow related to each other. 相似文献
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Karl-Ove Söderström 《Experimental cell research》1981,131(2):488-491
In this study it is shown that a cytoplasmic cell organelle, the chromatoid body, becomes labelled with [3H]uridine in the pachytene spermatocytes. The chromatoid body becomes labelled when the cells are first labelled for 2 h in the presence of [3H]uridine and thereafter chased for 9 h in the presence of unlabelled uridine. This labelling is inhibited by the specific RNA polymerase II inhibitor α-amanitin. Based on this it is suggested that part of the RNA synthesized in the pachytene spermatocytes is stored in the chromatoid body and transported to the postmeiotic spermatids where it is used in the differentiation of the spermatids. 相似文献
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A procedure for isolating the chromatoid body from the testis of 40-day-old rats was developed. Electron-microscopical analysis indicated that about 70% of the isolated organelles were chromatoid bodies, while the remaining structures corresponded to dense bodies and probably to satellites. Negative staining of the isolated organelles revealed the presence of polysome-like structures in about 20% of the chromatoid bodies suggesting that the polysomes were not due to contamination with cytoplasmic polysomes. Moreover, the presence of RNA in the stroma of the chromatoid body was confirmed by RNAse-gold staining. Preliminary electrophoretic analysis of the RNA extracted from the organelles revealed the presence of a complex population of RNAs including 5.8 and 5 S ribosomal RNAs but no tRNA. 相似文献
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Stimulation of (3H)uridine incorporation into nuclear RNA of rat kidney by vitamin D metabolites 总被引:1,自引:0,他引:1
Within 30–60 min after administration of 25-hydroxycholecalciferol or 30 min after 1,25-dihydroxycholecalciferol, the incorporation of [3H]uridine into the nuclear RNA of kidney is stimulated 1.6-fold or 3-fold, respectively. The results suggest that 1,25-dihydroxycholecalciferol is the active form responsible for the stimulation of RNA synthesis. It is suggested that specific RNA and protein synthesis may be involved in the renal reabsorption of ions initiated by vitamin D or its metabolites. 相似文献
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M Andonov 《Zeitschrift für mikroskopisch-anatomische Forschung》1990,104(1):46-54
Ultrastructure of the chromatoid body in rat spermatocytes and spermatids was studied by transmission electron microscopy. The following was found: 1. electron dense granules, 72.1 +/- 14.73 (SD) nm, that appeared to be both primary (assembling) and end (disassembling) structural subunits in the biogenesis of the chromatoid body, 2. relationship between chromatoid body and cytoplasmic microtubules, 3. ribbon-like structures and aggregates of 25 nm granules. The discussion focuses on a) a probable sequence of formation and breakdown of the chromatoid body, and b) the chromatoid body as an example of a common cellular design involving an interrelationship of dense material-smooth membranes-microtubules. 相似文献
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Yuko Onohara Toshiyuki Fujiwara Takanori Yasukochi Masaru Himeno Sadaki Yokota 《Histochemistry and cell biology》2010,133(6):627-639
The localization of vasa homolog protein in the spermatogenic cells of mice, rats, and guinea pigs was studied by immunofluorescence
and electron microscopies with the antibody against mouse vasa homolog (MVH) protein. By immunofluorescence microscopy, four
types of granular staining patterns were identified: (1) fine particles observed in diplotene and meiotic cells, (2) small
granules associated with a mitochondrial marker and appearing in pachytene spermatocytes after stage V, (3) strands lacking
the mitochondrial marker in late spermatocytes, and (4) large irregularly shaped granules in round spermatids. Immunoelectron
microscopy defined the ultrastructural profiles of these MVH protein-positive granules: the first type consisted of small
dense particles, the second had intermitochondrial cement (IMC), the third type, consisting of strands, had loose aggregates
of either material dissociated from IMC or 70–90-nm particles, and the fourth had typical chromatoid bodies (CBs). The results
suggest that MVH proteins function in these components of nuage. MVH protein-positive structures other than CBs disappeared
during meiosis and CB appeared first in early spermatids. The results suggest that the formation of nuage is discontinued
between spermatocytes and spermatids. The formation of nuage in spermatocytes and of CB in spermatids is discussed. 相似文献
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Incorporation of [5-3H]uridine and attachment of cells to glass during activation of lymphocytes induced by phytohaemagglutinin 下载免费PDF全文
D. R. Forsdyke 《The Biochemical journal》1968,108(2):297-302
1. Shortly after the addition of phytohaemagglutinin to cultures, partially purified pig blood lymphocytes showed increased labelling of RNA by [5-(3)H]uridine and began to attach to the glass of the culture tubes. 2. In the presence of phytohaemagglutinin most cells became attached to glass during the first 5hr. of culture; those first attaching had a low mean RNA/DNA ratio. In the absence of phytohaemagglutinin cell attachment to glass was diminished. 3. During the first 5hr. of culture the rates of increase of radioactivity/unit of DNA of the attached and unattached populations in the presence of phytohaemagglutinin were of the same order and exceeded that of cultures without phytohaemagglutinin. 4. The increase of labelling in cultures to which phytohaemagglutinin was added after cells had sedimented to glass was greater than that occurring in cultures in which cells were resuspended before phytohaemagglutinin was added. 相似文献