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Amphipyrinae have long been a catchall taxon for Noctuidae, with most members lacking discernible morphological synapomorphies that would allow their assignment to one of the many readily diagnosable noctuid subfamilies. Here data from seven gene regions (> 5500 bp) for more than 120 noctuid genera are used to infer a phylogeny for Amphipyrinae and related subfamilies. Sequence data for 57 amphipyrine genera – most represented by the type species of the genus – are examined. We present here the first large‐scale molecular phylogenetic study of Amphipyrinae and the largest molecular phylogeny of Noctuidae to date; several proposed nomenclatural changes for well‐supported results; and the identification of areas of noctuid phylogeny where greater taxon sampling and/or genomic‐scale data are needed. Adult and larval morphology, along with life‐history traits, for taxonomic groupings most relevant to the results are discussed. Amphipyrinae are significantly redefined; many former amphipyrines, excluded as a result of these analyses, are reassigned to other noctuid subfamily‐level taxa. Four genera, Chamaeclea Grote, Heminocloa Barnes & Benjamin, Hemioslaria Barnes & Benjamin and Thurberiphaga Dyar, are transferred to the tribe Chamaecleini Keegan & Wagner tribe n. in Acontiinae. Stiriina is elevated to Stiriinae rev. stat. , Grotellina is elevated to Grotellinae rev. stat. and Annaphilina is elevated to Annaphilini rev. stat. Acopa Harvey is transferred to Bryophilinae, Aleptina Dyar is transferred to Condicinae, Leucocnemis Hampson and Oxycnemis gracillinea (Grote) are transferred to Oncocnemidinae, Nacopa Barnes & Benjamin is transferred to Noctuinae and Narthecophora Smith is transferred to Stiriinae. Azenia Grote (and its subtribe Azeniina), Cropia Walker, Metaponpneumata Möschler, Sexserrata Barnes & Benjamin and Tristyla Smith are transferred to Noctuidae incertae sedis. Hemigrotella Barnes & McDunnough (formerly in subtribe Grotellina) is retained in Amphipyrinae. Argentostiria Poole and Bistica Dyar are retained in Stiriini but removed from incertae sedis position. This published work has been registered on ZooBank: http://zoobank.org/urn:lsid:zoobank.org:pub:4A140782‐31BA‐445A‐B7BA‐6EAB98ED43FA .  相似文献   
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The post-translational processing and maturation of the receptor for IgE (Fc epsilon R) on murine hybridoma B cells were studied to determine the carbohydrate content and the importance of processing events in cell surface expression and ligand (IgE) binding ability. Endo and exoglycosidase treatment demonstrated that the mature receptor is composed of two to three complex-type N-linked oligosaccharides and contains sialic acid. Pulse-chase experiments indicated that the receptor is synthesized as a 44,000 dalton precursor that begins to be processed by 1 hr to the mature 49,000 dalton form, and the latter is expressed at the cell surface by 2 hr. It was determined that the processing included the conversion of N-linked oligosaccharides to the complex type as well as an additional processing event, because in the presence of tunicamycin, the receptor is synthesized as a 36,000 dalton precursor that is processed to a 38,000 dalton species. Analysis of the effects of tunicamycin treatment and endo F digestion on soluble Fc epsilon R isolated from cell supernatants demonstrated the existence of several m.w. species of Fc epsilon R fragments, and indicated that only the higher m.w. fragments were N-glycosylated. The use of several inhibitors of the N-linked carbohydrate processing pathway demonstrated that the addition of core N-linked side-chains, but not their processing to the complex type, is required for cell surface expression of Fc epsilon R. Also, processing of N-linked carbohydrate is not required for ligand binding activity. Finally, IgE affinity chromatography indicated that the 49,000 and 38,000 dalton (tunicamycin) Fc epsilon R bind IgE more effectively than their precursor forms, 44,000 and 36,000 daltons, respectively, indicating that a processing event independent of N-linked glycosylation is necessary for optimal ligand binding activity.  相似文献   
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A D Keegan  J H Pierce  J Artrip  M Plaut    W E Paul 《The EMBO journal》1991,10(12):3675-3682
IL-3 dependent mast cell lines produce cytokines in response to Fc receptor cross-linkage or to ionomycin. In this study we have observed that cells pre-cultured in IL-3 produce 10-100 times more cytokine after receptor cross-linkage in comparison with IL-4 pre-cultured cells. Although several hematopoietin receptors, including those for IL-3, IL-4 and EPO, do not contain tyrosine kinase domains, their occupancy with ligand causes tyrosine phosphorylation of specific cellular substrates. Therefore, the contribution of tyrosine kinase activation to the ability of an IL-3 dependent mast cell line, CFTL-15, to produce cytokines was analyzed. The CFTL-15 cells were transfected with growth factor receptors containing ligand-inducible tyrosine kinase domains (EGFR and PDGFR, and CSF-IR) or with the EPOR. All of the transfectants were able to proliferate in response to IL-3 or to their respective growth factor and to produce IL-3 in response to IgE receptor cross-linkage. Stimulation of the EGFR and PDGFR transfectants with their respective ligands resulted in the production of IL-3, IL-6, and GM-CSF. Stimulation of the CSF-1R or EPOR transfectants with growth factor alone failed to induce cytokine production. However, in co-stimulation assays each of the growth factors enhanced the amount of cytokine produced in response to Fc epsilon RI cross-linkage. The ability of these stimuli to induce tyrosine phosphorylation in the transfectants was analyzed. Fc epsilon RI cross-linkage in the transfectants routinely induced the tyrosine phosphorylation of 145, 86 and 72 kDa proteins, with occasional phosphorylation of 55, 52, and 40 kDa proteins.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Studies on dog heartworm in South Texas   总被引:1,自引:0,他引:1  
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Th cell clones are known to induce an IL-4 dependent polyclonal IgE synthesis. Because IL-4 can induce the expression of the low affinity FcR for IgE (Fc epsilon RII) the ability of Th cell clones to induce Fc epsilon RII on purified splenic B cells was analyzed. It was found that a TH2 clone could cause a 50- to 100-fold superinduction of Fc epsilon RII after 2 days in culture; after 3 days, the Fc epsilon RII levels had almost returned to base line. The superinduction was inhibited by an anti-IL-4 antibody, 11B11, indicating its dependence on IL-4. A TH1 clone could cause a modest (four fold) induction of Fc epsilon RII, and this induction was not influenced by 11B11. A similar Fc epsilon RII induction was seen when using the supernatant from activated TH1 cells. The component(s) causing this relatively low level Fc epsilon RII induction is not known; a variety of known lymphokines were tested, and only IL-4 demonstrated any capacity for Fc epsilon RII induction on LPS-activated B cells. Addition of rIL-4 at concentrations of 400 U/ml or greater to the TH1 culture was sufficient to cause a Fc epsilon RII superinduction similar to that seen with the TH2 clone, while 40 U/ml was not. In order to determine a potential role for the Fc epsilon RII or its soluble fragment on the IgE synthesis mediated by TH2, a monoclonal anti-Fc epsilon RII, B3B4, was added to the culture. The addition of B3B4 did not have an influence on IgE levels in this system.  相似文献   
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Cross-linking of 125I-IL-4 to the surface of cells expressing IL-4R yields as the major IL-4-binding molecules, polypeptide chains with inferred m.w. of approximately 70,000 (p70) and approximately 120,000 to 140,000 (p120-p140). The demonstration that the functional product of the IL-4R cDNA clone has m.w. of approximately 140,000 and that no p70 product is detected in transfected COS-7 cells has led to an uncertainty regarding the nature of p70. To study this issue, we examined the relationship of the IL-4-binding molecules p120 and p70 and, in parallel, attempted to immunoprecipitate p70 from surface and internally labeled cells using IL-4 and two anti-IL-4R antibodies (M1 and M2), bound to Affigel 10, as ligands. Cross-linked complexes containing 125I-IL-4 and p70 or p120 were isolated and digested with chymotrypsin or with V8 protease. Three distinct IL-4-binding peptides could be compared; these were indistinguishable for cross-linked p70 and p120, strongly implying that p70 and p120 were structurally related. Furthermore, immunoprecipitates made with IL-4 or anti-IL-4R-Affigel did not contain p70. This led us to conclude that p70 is a breakdown product of p120. A second IL-4-binding molecule of 40,000 Da (p40) expressing the M1 and M2 epitopes of the IL-4R was detected and appears to be the product of an mRNA coding for the soluble form of the receptor. mRNA for p40 was detected in both the T cell line CT.4R and the mast cell line CFTL.12 using polymerase chain reaction primers unique to this species of message. Pulse-chase studies of IL-4R in [35S] methionine-labeled cells indicates that p40 is derived from a 42,000-Da precursor that is detectable at the end of the pulse period, and thus, further argue that p40 is an independently translated molecule and not a degradation product of p120. Although p40 has been previously shown to be a soluble, truncated form of the receptor, we failed to observe secretion of p40 into the medium by internally labeled CT.4R cells.  相似文献   
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