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1.
2.
Genetic characterization of mouse immunoglobulin allotypic determinants (allotopes) defined by monoclonal antibodies 总被引:6,自引:0,他引:6
Chun-Ming Huang Marilyn Parsons Vernon T. Oi Huei-Jen Su Huang Leonard A. Herzenberg 《Immunogenetics》1983,18(4):311-321
We have generated a new series of monoclonal antibodies recognizing allotypic determinants on mouse IgG1, IgG2a, and IgG2b. In this communication we describe their reactivities with immunoglobulins of the inbred mouse strains. Comparison with serology charts indicates that many of these monoclonal antibodies detect allotypic specificities previously defined by conventional antisera; others define previously undescribed specificities. Strain and isotype distribution allows us to assign five new allotypic specificities to Igh-1 and three new specificities to Igh-3. In addition, on the basis of reactivity with the monoclonal antibodies, we have defined a new Igh haplotype in SWR/J mice, Igh
p.Abbreviations used in this paper Igh
immunoglobulin heavy chain
- SDS
sodium dodecyl sulfate 相似文献
3.
Observations on the mechanism of indirect induction by mating with ultraviolet-irradiated col I donors 总被引:2,自引:0,他引:2
Marilyn Monk 《Molecular & general genetics : MGG》1967,100(3):264-274
Summary Irradiation of the colI donor itself is required to initiate indirect induction of phage following mating with a lysogenic recipient. Attempts to demonstrate that some other cytoplasmic inducer is responsible for induction have been negative. However the level of transfer of a viable (colicin-producing) colI factor (to a non-lysogenic recipient) is not correlated with the transfer of indirect induction (to a lysogenic recipient) either with respect to relative UV sensivities, or relative kinetics. Transfer of viable colI factor from the irradiated donor is delayed for up to 40 minutes whereas indirect induction is initiated early after contact. There is some lethality and inhibition of division of recipient cells mated with the irradiated donor, these effects similarly being initiated extremely early after cell contact. The question as to whether these effects of mating with an irradiated donor on the recipient follow transfer of inviable colI, or reflect a disturbance of transfer itself remains unresolved. 相似文献
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6.
Kimberlee K. Wallace Gregory F. Payne Marilyn K. Speedie 《Journal of industrial microbiology & biotechnology》1990,6(1):43-48
Summary A defined medium containing glucose and ammonium as the sole carbon and nitrogen sources was developed to support growth and streptonigrin production. In this defined medium, increased initial levels of ammonium resulted in increased growth suggesting that nitrogen is the growth limiting nutrient. In some cases, increased initial ammonium levels resulted in decreased specific streptonigrin productivity, suggesting that nitrogen regulatory mechanisms may adversely affect streptonigrin biosynthesis. This suggestion that nitrogen regulation adversely affects antibiotic biosynthesis is further supported by results from two studies in which the ammonium supply to the cells was controlled. In the first study, streptonigrin productivity and final titer were enhanced by the addition of an ammonium trapping agent. In the second experiment, when ammonium chloride was fed slowly throughout the course of cultivation, the production phase was lengthened and the maximum antibiotic concentration was enhanced compared to the batch controls containing either the same initial or the same total ammonium chloride levels. Although our results indicate streptonigrin production may be subject to nitrogen regulatory mechanisms, the effect of nitrogen on streptonigrin production cannot be strictly correlated to the extracellular ammonium concentration. In fact, we observed that when ammonium was depleted from the medium, streptonigrin production ceased. 相似文献
7.
Frances Jurnak Marilyn D. Yoder Richard Pickergill John Jenkins 《Current opinion in structural biology》1994,4(6)
A new type of structural domain, composed of parallel β-strands folded into a coiled structure, has been observed in several protein structures within the past year. An analysis of the basic motif indicates that there are two distinct types, with variations likely to be discovered in the future. 相似文献
8.
Marilyn J. Anderson 《In vitro cellular & developmental biology. Animal》1993,29(2):145-152
Summary Explants and dissociated cells from normal adult spinal cord and regenerating cord of the teleostApteronotus albifrons were grown in vitro for periods of 8 to 12 wk. During this time the neurons showed extensive neurite outgrowth. Neurite outgrowth
from tissue explants and dissociated cells of regenerated spinal cord starts sooner and is more profuse than that from normal
(unregenerated) cord. Neurite outgrowth is maximized by using adhesive substrata and a high density of explants or dissociated
cells. Inasmuch asApteronotus does regenerate its spinal cord naturally after injury, whereas mammals do not, this culture system will be useful to study
factors that control (permit) regeneration of spinal neurons in this adult vertebrate. 相似文献
9.
Richard Safford Marilyn T. Moran Jacqueline De Silva Susan J. Robinson Susan Moscow Carl D. Jarman Antoni R. Slabas 《Transgenic research》1993,2(4):191-198
Medium chain hydrolase (MCH) is an enzyme which regulates the chain length of fatty acid synthesis specifically in the mammary gland of the rat. During lactation, MCH interacts with fatty acid synthase (FAS) to cause premature release of acyl chains, thus providing medium chain fatty acids for synthesis of milk fat. In this study we have investigated the ability of rat MCH to interact with the phylogenetically more distant FAS structure present in plant systems and to cause a perturbation of fatty acid synthesis. Inin vitro experiments, addition of purified MCH to rapeseed homogenates was found to cause a significant perturbation of fatty acid synthesis towards medium chain length products. The rat MCH gene was expressed in transgenic oilseed rape using a seed specific rape acyl carrier protein (ACP) promoter and a rape ACP plastid targeting sequence. Western analysis showed MCH protein to be present in transgenic seed and for its expression to be developmentally regulated in concert with storage lipid synthesis. The chimaeric preprotein was correctly processed and immunogold labelling studies confirmed MCH to be localized within plastid organelles. However, fatty acid analysis of oil from MCH-expressing rape seed showed no significant differences to that from control seed. 相似文献
10.
Evidence for Nerve Growth Factor-Potentiating Activities of the Nonpeptidic Compound SR 57746A in PC12 Cells 总被引:2,自引:0,他引:2
Anne Pradines Marilyn Magazin Pascal Schiltz Gérard Le Fur Daniel Caput Pascual Ferrara 《Journal of neurochemistry》1995,64(5):1954-1964
Abstract: SR 57746A {1-[2-(naphth-2-yl)ethyl]-4-(3-trifluoromethylphenyl)-1,2,5,6-tetrahydropyridine hydrochloride} exhibits neurotrophic activities in vivo and in vitro. We used the rat pheochromocytoma PC12 cell line to investigate in vitro cellular changes induced by SR 57746A. A significant increase in the percentage of cells bearing neurite-like processes was obtained in cells treated by SR 57746A and nerve growth factor (NGF) compared with NGF treatment alone. SR 57746A added alone, however, had no effect on morphogenesis or on survival of cells in serum-free medium. In contrast, SR 57746A induced a "priming" effect on PC12 cells for neurite outgrowth within 6 h of addition of the protein tyrosine kinase inhibitor genistein. An increase in α-actinin content resulted from treatment with SR 57746A. Expression of NGF-mediated acetylcholinesterase and choline acetyltransferase was enhanced within 5 days by SR 57746A. The molecule also induced rapid F-actin redistribution. Within 2 min of incubation, outgrowth of F-actin-containing filopodia was clearly visible at the cell periphery, as previously shown with NGF. It is interesting that this effect of SR 57746A could be mimicked by protein tyrosine kinase inhibitors and abolished by preincubation with sodium orthovanadate, a protein tyrosine phosphatase inhibitor. 相似文献