共查询到20条相似文献,搜索用时 15 毫秒
1.
Hideko Tsuzuki Motonobu Yoshida Kazuo Onitake Kenji Aketa 《Biochemical and biophysical research communications》1977,76(2):502-511
The substance which seems to be responsible for the sperm-binding at fertilization was successfully purified from unfertilized eggs of the sea urchin, . It completely cancelled the fertilizing capacity only of homologous sperm without reducing their motility. The antiserum against this substance made only homologous eggs incapable of binding sperm. The methods employed for purification were (1) extraction by urea, (2) fractionation by calcium acetate, (3) salting-out by ammonium sulfate, (4) gel filtration and (5) ion-exchange chromatography. This substance was electrophoresed on cellulose-acetate strip as a single band which was stained with Amido Black, and could not be split by 6 M guanidine hydrochloride. 相似文献
2.
When sea urchin sperm is pretreated with sperm-binding protein prepared from the vitelline membrane of eggs of homologous species, it loses its fertilizing capacity entirely without losing its motility. It is not affected at all by sperm-binding protein from heterologous species. Neither agglutination nor acrosome reaction is evoked by the pretreatment. It is suggested that the sea urchin spermatozoon has on the apical part of its head a component which is complementary to the sperm-binding protein of the egg, and that the observed loss of the fertilizing capacity is caused by antedated interaction of this component with sperm-binding protein added before insemination. 相似文献
3.
A 225 K dalton glycoprotein is the active core structure of the sperm-binding factor of the sea urchin, Anthocidaris crassispina 总被引:1,自引:0,他引:1
Fab fragments against 225 000 D glycoprotein (225 K), 87 000 D protein (87K) 80 000 D glycoprotein (80 K) of partially purified sperm-binding factor of Anthocidaris crassispina were prepared, and their effects upon fertilizability of dejellied homologous and heterologous eggs examined. Only the 225 K Fab impaired the fertilizability of homologous, not heterologous eggs by decreasing their sperm-binding capacity. It was concluded that 225 K glycoprotein is the active core structure of the sperm-binding factor of this species. The possible participation of the other two proteins as residual ingredients of the sperm-binding factor was also discussed. Immunofluorescence studies showed that 225 K core protein is localized on the whole surface of unfertilized eggs and of fully-grown oocytes. The fluorescence disappeared following fertilization. 相似文献
4.
Sperm binding to an egg model composed of agarose beads 总被引:3,自引:0,他引:3
A sperm-binding factor of the eggs of the sea urchin Hemicentrotus pulcherrimus or Anthocidaris crassispina, was coupled to agarose beads. Upon contact with these beads, the spermatozoa exhibited an acrosome reaction and bound to them. No binding occurred to BSA-coupled beads or to beads missing active groups. When coupled beads were pretreated with a sperm factor, which is the probable counterpart to the sperm-binding factor, they could no longer bind sperm. Reciprocal cross-binding between the above two species was not successful, but H. pulcherrimus sperm became capable of binding to A. crassispina beads if they first underwent acrosome reaction in egg water. Sperm of two of seven other echinoderms examined was able to bind to the coupled beads. 相似文献
5.
Shigenori Tanaka Takanori Nakamura Takashi Morita Sadaaki Iwanaga 《Biochemical and biophysical research communications》1982,105(2):717-723
Exposure of amebocytes to bacterial endotoxins (lipopolysaccharides, LPS) results in the activation of the coagulation system, which consists of several protein components. During the separation of these components, a potent anticoagulant, named tentatively anti-LPS factor, which inhibits the endotoxin-mediated coagulation reaction, was found in both amebocytes from the hemolymphs of and . The principle purified partially from amebocyte lysate had a molecular weight less than 10,000, as judged with the ordinary gelfiltration experiment. It inhibited specifically the activation of factor B, which has recently been characterized to be a coagulation factor highly sensitive to LPS, but it did not inhibit the activities of the active factor B and the active clotting enzyme separated from the lysate. The inhibitory activity of anti-LPS factor disappeared almost completely by the treatments with pronase-P and subtilisin, suggesting its polypeptide-like substance, but it resisted to a boiling treatment. A possible site of the anticoagulant action on the coagulation system was discussed. 相似文献
6.
Immunological species specificity of sperm-binding protein from eggs of the 4 sea urchin species, Hemicentrotus pulcherrimus, Pseudocentrotus depressus, Anthocidaris crassispina and Temnopleurus toreumaticus, was examined by means of double immuno-diffusion technique in agar. Ca-soluble fraction of sperm-binding protein which is considered to be responsible for initial sperm-egg bonding at fertilization, has species-specific antigenic component. Correlations in antigenic constituents among the 4 species are described. 相似文献
7.
A new eukaryotic RNA polymerase factor: a factor from chicken myeloblastosis cells which stimulates transcription of denatured DNA 总被引:1,自引:0,他引:1
R Chuang L Chuang J Laszlo 《Biochemical and biophysical research communications》1974,57(4):1231-1239
A heat-stable protein factor, capable of stimulating RNA synthesis by nuclear RNA polymerase II, was found in isolated nuclei of chicken myeloblastosis cells. It is adsorbed to a DEAE-Sephadex column used for RNA polymerase purification and then is eluted with 0.1 M ammonium sulfate. This factor appears to differ from previously reported eukaryotic RNA polymerase factors in its property of stimulating the activity of denatured (or single-stranded) DNA template. When heated, this factor contains no detectable endonuclease or exonuclease activity. The degree of stimulation is greater with chicken myeloblastosis RNA polymerase IIb than IIa and is most efficient when homologous DNA is used as template. This factor causes no stimulation of RNA polymerase. 相似文献
8.
Univalent antibody (Fab fragments) against sperm-binding factor inhibits the fertilization of eggs species-specifically. The sperm-binding factor was partially purified from unfertilized eggs of the sea urchin Anthocidaris crassispina by monitoring its neutralizing effect on fertilization inhibiting Fab fragments. It formed two species-specific precipitin lines by the double-immunodiffusion test and gave three main bands of protein with apparent molecular weights of 80,000, 87,000 and 225,000, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Carbohydrate was detected in the first and third of these protein bands. 相似文献
9.
J Y Chan C E Burrowes F M Habal H Z Movat 《Biochemical and biophysical research communications》1977,74(1):150-158
Human factor XII was activated by adsorption onto kaolin in the presence of high molecular weight kininogen. The washed kaolin-containing precipitates activate prekallikrein to kallikrein. When antithrombin III was added to the reaction mixture, the conversion of prekallikrein to kallikrein was inhibited, the degree of inhibition depending on the concentration of antithrombin and the time of incubation. Heparin had a slight enhancing effect with low concentrations of antithrombin and short incubation times. However, the inhibition of the generated kallikrein by antithrombin III was markedly enhanced by heparin. Antithrombin III inhibited also the effect of activated factor XII on the partial thromboplastin time, using factor XII-deficient plasma. Of other plasma proteinase inhibitors used (α1-antitrypsin, α2-macroglobulin, C-inactivator) only C-inactivator inhibited activated factor XII. 相似文献
10.
11.
Histone messenger RNA is detectable in both the maternal RNA which is stored in the unfertilized sea urchin egg and in the RNA species which are synthesized after fertilization. Hybridization competition experiments show that sequences similar to pulse-labeled 912S RNA from morulae are present in total RNA from unfertilized eggs as well as that from later stages. The proportion of histone mRNA in cellular RNA increases after fertilization, reaching a maximum at the morula stage. Although these messengers are still present in hatched blastulae and gastrulae, they represent a smaller proportion of total RNA compared with earlier stages. 相似文献
12.
Fred Punzo 《Journal of experimental marine biology and ecology》1982,60(1):71-76
The role of external calcium ions in the fertilization of the sea urchin, Strongylocentrotusfranciscansus (A. Agassiz), was studied. When eggs were inseminated with jelly-treated sperm in artificial sea waters containing various concentrations of calcium, the percentage of fertilization decreased with decreasing concentrations of calcium. A small amount of external calcium ions was also found to be essential for fertilization by spermatozoa with reacted acrosomes. The binding capacity of jelly-treated spermatozoa to eggs was, however, not adversely affected by a calcium deficiency. These results suggest that calcium ions are required not only for the initiation of the acrosome reaction, but also for successful levels of fertilization following sperm-binding to eggs even after the acrosome reaction has occurred. 相似文献
13.
J Sy N H Chua Y Ogawa F Lipmann 《Biochemical and biophysical research communications》1974,56(3):611-616
Ribosomes obtained from (ATCC 8185) were slightly active in synthesizing guanosine polyphosphates, which activity was greatly stimulated by addition of stringent factor. chloroplast ribosomes did not produce guanosine polyphosphates on incubation but responded with abundant synthesis to addition of the stringent factor from . In contrast, cytoplasmic ribosomes from the same organism did not respond. Interchange experiments between either subunit from chloroplasts with the counterparts showed good activity. When the small subunit of cytoplasmic ribosomes was combined with the large subunit of or of chloroplasts, a small but definite response was obtained. 相似文献
14.
In this study, the cells producing T-cell growth factor (TCGF) in the rat MLR were characterised with respect to the antigens defined by , and OX8 monoclonal antibodies. Unfractionated lymphocytes and cells depleted of OX8 positive cells were found to be fully capable of producing TCGF, whereas lymphocytes depleted of positive cells had lost this ability. Parallel experiments demonstrated that cells selected by the fluorescence-activated cell sorter for the expression of defined antigens were potent producers of TCGF. Further studies suggested a functional role for the antigen defined by antibody because the addition of this antibody to a MLR abrogates TCGF production. These findings suggest that the important immunomodulatory functions of positive lymphocytes could be exercised via the synthesis of essential lymphokines. 相似文献
15.
Tyge Greibrokk Jan Hansen Ronald Knudsen Yiu-Kuen Lam Karl Folkers Cyril Y. Bowers 《Biochemical and biophysical research communications》1975,67(1):338-344
A preparation of < 100 ng of a prolactin inhibiting factor was isolated which could be essentially pure, because of symmetrical single peaks by high pressure liquid chromatography. The activity was at < 5 ng which is the highest potency reported by anyone. The paucity of < 100 ng/80,000 hypothalami necessitates patience for definitive data on more product from 240,000 to 450,000 hypothalami. Weight was estimated by comparing UV absorption at 220 nm with that of synthetic peptides. This preparation is not a catecholamine by chromatography, and gives new and timely credence to the concept that prolactin secretion is mediated by complex mechanisms including a peptide inhibiting factor and a catecholamine. 相似文献
16.
Humoral (H) endorphin, a novel endogenous opioid ligand detected in brain, blood and cerebrospinal fluid was tested in a series of opiate sensitive assays. H-endorphin displaced radiolabeled enkephalin from its specific bindings sites and inhibited the electrically evoked contraction of the guinea pig ileum and mouse vas deferens. When injected to unanesthesized animals, humoral endorphin induced analgesia in rats and mydriasis in mice. The activity of H-endorphin both and attests to its opioid nature. However, while its antinociceptive effect was blocked by naloxone, mydriasis induced by H-endorphin was resistant to the effect of the opiate antagonist. Similarly, intermediate concentrations of naloxone inhibited the effect of H-endorphin on the guinea pig ileum while its effect on the mouse vas deferens was completely refractory to naloxone. The physiological function of humoral endorphin in various naturally occuring states that show similar paradoxical interactions with naloxone is discussed. 相似文献
17.
Fertilization of frog eggs by frog sperm is inhibited if the egg's membrane potential is positive (N. L. Cross and R. P. Elinson, 1980, Dev. Biol.75, 187–198); however, fertilization of salamander eggs by salamander sperm does not depend on membrane potential (M. Charbonneau, M. Moreau, B. Picheral, J. P. Vilain, and P. Guerrier, 1983, Dev. Biol.98, 304–318). Since salamander sperm can fertilize frog eggs, we have investigated whether this cross-fertilization is voltage dependent. If, during insemination with Notophthalmus sperm, Xenopus eggs were voltage clamped between +7 and +20 mV, fertilization proceeded in (70%) of the clamped eggs, compared to (79%) of the neighboring eggs. In control experiments in which voltage-clamped Xenopus eggs were inseminated with Xenopus sperm, fertilization proceeded in only (10%) of the clamped eggs, compared to (98%) of the neighbors. Similar results were obtained with cross-fertilization experiments between Notophthalmus sperm and Rana eggs. These experiments indicate that the voltage dependence of fertilization depends on the species of sperm. 相似文献
18.
G Wiche 《Biochemical and biophysical research communications》1979,89(2):620-626
Rat glioma C6 cell polyribosomal preparations were tested in a heterologous system for their ability to direct the synthesis of nerve growth factor related polypeptides. Two major polypeptides of MW ~ 21,000 and ~ 43,000 respectively were found, both of which were immunoprecipitable with specific anti-mouse 2.5S nerve growth factor serum. After incubation of synthesized proteins with submaxillary gland extract the bulk of these protein species was converted into immunoprecipitable material of MW ~ 13,000, which comigrated in sodium dodecyl sulfate/polyacrylamide gel electrophoresis with mouse 2.5S nerve growth factor. 相似文献
19.
Julián Gómez-Cambronero María L. Nieto JoséM. Mato Mariano Sánchez-Crespo 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1985,845(3):511-515
The enzyme lyso-platelet-activating factor:acetyl-CoA acetyltransferase (EC 2.3.1.67) was assayed in microsomal fractions from rat spleens. The addition of micromolar Ca2+ rapidly enhanced acetyltransferase activity and this activation was reversed by the addition of EGTA in excess of Ca2+. The effect of Ca2+ was on the apparent of the enzyme for the substrate acetyl-CoA without showing any significant effect on the of the acetylation reaction. When microsomes were isolated in the presence of 5 mM EGTA, to remove endogenous calmodulin, the same enhancing effect of Ca2+ on the acetylation reaction was observed. The addition of exogenous calmodulin to this preparation had no effect on the enzyme activity. Preincubation of spleen microsomes with the calmodulin inhibitor trifluoperazine decreased acetyltransferase in both the presence and the absence of Ca2+, indicating an effect of this drug independently of calmodulin. The addition of Mg-ATP to the assay mixture also had no effect on the acetylation reaction. These data suggest that Ca2+ modulates acetyltransferase activity from rat spleen microsomes by a mechanism that seems to be independent of calmodulin or protein phosphorylation. 相似文献
20.
Periodic change in the content of adenosine 3'5'-cyclic monophosphate with close relation to the cycle of cleavage in the sea urchin egg 总被引:2,自引:0,他引:2
I Yasumasu A Fujiwara K Ishida 《Biochemical and biophysical research communications》1973,54(2):628-632
The content of adenosine 3′5′-cyclic monophosphate (cAMP) in sea urchin eggs, , increased gradually after fertilization to about 10-fold that in unfertilized egg, and decreased rapidly during cytokinesis of the egg to the level found in unfertilized egg. The same profile of the change in cAMP content as found during first cleavage, was also observed during second and third cleavage. The periodic change in cAMP content in the sea urchin egg seems to be repeated with close relation to the cycle of cytokinesis. 相似文献