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41.
Proton-translocating ATPase and lysosomal cystine transport 总被引:6,自引:0,他引:6
A J Jonas M L Smith W S Allison P K Laikind A A Greene J A Schneider 《The Journal of biological chemistry》1983,258(19):11727-11730
A proton-translocating ATPase was identified in highly purified lysosomes from Epstein-Barr virus-transformed human lymphoblasts. Activity of this ATPase caused acidification of highly purified, fluorescein isothiocyanate dextran-loaded lysosomes and correlated with the ATP-dependent efflux of lysosomal cystine. The lysosomal ATPase was distinct from mitochondrial F1-ATPase in its responses to a variety of inhibitors. Although ATP-dependent lysosomal cystine efflux is not demonstrable in cultured lymphoblasts from individuals with nephropathic cystinosis, ATPase activity and acidification in lysosomes from these cells is comparable to that in noncystinotic lysosomes. ATPase activity in lymphoblasts from normal individuals was 543 +/- 79 nmol/mg/min while in lymphoblasts from cystinotic individuals this activity was 541 +/- 25 nmol/mg/min. ATP-dependent acidification of lysosomes from normals was -0.5 +/- 0.1 pH units compared to -0.5 +/- 0.1 pH units in cystinotic lysosomes. Activity of the lysosomal proton-translocating ATPase is a necessary, but not sufficient, condition for lysosomal cystine efflux. 相似文献
42.
In vitro immune mechanisms associated with clearance of microfilariae of Dirofilaria immitis 总被引:3,自引:0,他引:3
An in vitro system has been developed to elucidate potential immune mechanisms associated with clearance of microfilariae (Mf) from the bloodstream in canine Dirofilaria immitis infection. Granulocytes as well as mononuclear cells adhere to Mf of Dirofilaria immitis in the presence of immune serum. Only granulocytes, however, were capable of killing Mf, whereas PBMC attach to but do not effectively kill Mf. In the presence of granulocytes 1% +/- 1, 10% +/- 2, and 12% +/- 3 of Mf were killed by heated normal (NDS), patent (PS), and occult serum (OS), respectively, after an 18-hr incubation. With the addition of fresh NDS there was an increase in killing to 5% +/- 1 (p less than 0.025) with heat-inactivated NDS, to 12% +/- 3 in the presence of PS and to 77% +/- 12 (p less than 0.005) in the presence of OS. On further purification of granulocyte cell populations with metrizamide gradients, neutrophils were found to be the predominant effector cells with 73% +/- 18 killing with neutrophils and 18% +/- 6 with eosinophils (p less than 0.0005). Only with neutrophils was a significant increase in killing of Mf observed when fresh NDS was added to delta OS. Fractionation of OS by gel filtration suggested that IgM was the opsonizing antibody in the occult serum. In addition, immunofluorescent studies showed only IgM bound to the surface on Mf on incubation in OS. The involvement of complement in the fresh serum enhancement of killing was supported by the finding, by immunofluorescence, of surface C3 on Mf after incubation in fresh OS. 相似文献
43.
Distribution of membrane cholesterol of adrenal cortical cells after corticotropin stimulation. 总被引:1,自引:0,他引:1 下载免费PDF全文
Membrane cholesterol in adrenal cortical cells is enriched in the plasma membrane. Stimulation of isolated adrenal cortical cells with corticotropin leads to the production of corticosterone. At high levels of corticotropin, cholesterol for corticosterone synthesis arises by hydrolysis of cellular cholesteryl ester, whereas at lower levels of corticotropin cholesteryl ester levels are unchanged from control values and there is a decrease in plasma-membrane cholesterol levels. 相似文献
44.
Arthur E. Greene Jesse Charney Warren W. Nichols Lewis L. Coriell 《In vitro cellular & developmental biology. Plant》1972,7(6):313-322
Summary Three mosquito cell cultures designated as Suitor's clone ofAedes aegypti, Culiseta inornata andAedes vexans were shown to be moth by immunological, karyological, and isozyme analyses. The cells reacted with rabbit antimoth serum
but not rabbit antimosquito serum. Chromosome analyses indicated Lepidopteran rather than Dipteran morphology, and three isozyme
systems were confirmative. Any one of these assays would be sufficient to indicate that contamination had occurred and could
be used as a periodic check for identity of cell cultures. Morphology and growth characteristics are also valid criteria to
distinguish between these particular orders of insect cells.
These studies were supported by Grant CA-04953-12 from the National Cancer Institute; General Research Support Grant FR-5582
from the National Institues of Health; and Grant-in-Aid Contract M-43 from the State of New Jersey.
Recipient of Research Career Award 5-K3-16,749. from the National Institutes of Health. 相似文献
45.
Arthur E. Greene Jesse Charney Warren W. Nichols Lewis L. Coriell 《In vitro cellular & developmental biology. Plant》1972,7(5):313-322
Summary Three mosquito cell cultures designated as Suitor's clone ofAedes aegypti, Culiseta inornata, andAedes vexans were shown to be moth by immunological, karyological, and isozyme analyses. The cells reacted with rabbit antimoth serum
but not rabbit antimosquito serum. Chromosome analyses indicated Lepidopteran rather than Dipteran morphology, and three isozyme
systems were confirmative. Any one of these assays would be sufficient to indicate that contamination had occurred and could
be used as a periodic check for identity of cell cultures. Morphology and growth characteristics are also valid criteria to
distinguish between these particular orders of insect cells.
These studies were supported by Grant CA-04953-12 from the National Cancer Institute; General Research Support Grant FR-5582
from the National Institutes of Health; and Grant-in-Aid Contract M-43 from the State of New Jersey.
Recipient of Research Career Award 5-K3-16,749 from the National Institutes of Health. 相似文献
46.
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48.
Procedures are described for phosphorylating protected nucleotides, oligonucleotides and phosphoramidate oligonucleotide derivatives at the 3′-hydroxyl group. The conditions (phosphorylation with phosphorus oxychloride and pyridine in dioxane followed by hydrolysis with aqueous pyridine) are sufficiently mild that base labile (trifluoroacetylamino; β-cyanoethyl phosphotriester) and acid labile (O-monomethoxytrityl; phosphoramidate) functions are retained intact. Application of the technique is illustrated by the synthesis of dpT, dTp, d(CF3CONH)Tp, dTpNTp, and dTpNTpNTp. In addition, the utilization of phosphorus oxychloride in joining thymidine derivatives and dinucleoside phosphotriester blocks via phosphodiester links is described. 相似文献
49.
50.
Endogenous gibberellins of a radiation induced single gene dwarf mutant of bean 总被引:2,自引:2,他引:0 下载免费PDF全文
The distribution of endogenous gibberellins in Dwarf-1, a single gene dwarf mutant of Mexico 80-R red beans, was studied. Parallel extraction and fractionation of seeds of this mutant and those of a normal homozygous line followed by thin layer chromatography and bioassays using Rumex obtusifolius, wheat seed endosperm and dwarf bean plants revealed that a stem elongation control factor was contained in the non-acidic fraction from normal, but not from Dwarf-1, seeds. It was concluded that the single gene mutation causes a block either in gibberellin precursor formation or in production of a non-acidic fraction gibberellin-like substance. 相似文献