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101.
Transformation of murine bone marrow cells with combined v-raf-v-myc oncogenes yields clonally related mature B cells and macrophages. 总被引:5,自引:1,他引:4 下载免费PDF全文
M Principato J L Cleveland U R Rapp K L Holmes J H Pierce H C Morse rd S P Klinken 《Molecular and cellular biology》1990,10(7):3562-3568
Murine bone marrow cells infected with replication-defective retroviruses containing v-raf alone or v-myc alone yielded transformed pre-B cell lines, while a retroviral construct containing both v-raf and v-myc oncogenes produced clonally related populations of mature B cells and mature macrophages. The genealogy of these transformants demonstrates that mature myeloid cells were derived from cells with apparent B-lineage commitment and functional immunoglobulin rearrangements. This system should facilitate studies of developmental relationships in hematopoietic differentiation and analysis of lineage determination. 相似文献
102.
Appearance of enzyme activities catalyzing conversion of sterigmatocystin to aflatoxin B1 in late-growth-phase Aspergillus parasiticus cultures 总被引:5,自引:0,他引:5
T E Cleveland A R Lax L S Lee D Bhatnagar 《Applied and environmental microbiology》1987,53(7):1711-1713
Two activities involved in terminal pathway conversion of sterigmatocystin to aflatoxin B1 were isolated from an aflatoxin-nonproducing mutant of Aspergillus parasiticus (avn-1), and the time course of appearance of the activities in culture was determined. Subcellular fractionation of fungal mycelia resolved the two activities into a postmicrosomal activity which catalyzed conversion of sterigmatocystin to O-methylsterigmatocystin and a microsomal activity which converted O-methylsterigmatocystin to aflatoxin B1. The two activities were absent in 24-h-old cells, increased to optimum levels during the stationary phase, and then declined. 相似文献
103.
Characterization of murine A-raf, a new oncogene related to the v-raf oncogene. 总被引:12,自引:5,他引:7 下载免费PDF全文
M Huleihel M Goldsborough J Cleveland M Gunnell T Bonner U R Rapp 《Molecular and cellular biology》1986,6(7):2655-2662
A 1.6-kilobase cDNA (A-raf) has been isolated from a murine spleen cDNA library which encodes part of a protein related to the raf oncogene. Its amino acid sequence has 85% homology to raf in a central portion of 100 amino acids. In contrast to raf, A-raf shows a highly restricted tissue distribution of expression, with highest levels observed in epididymis, followed by intestine. When incorporated into a retrovirus, the resulting gag-A-raf fusion gene causes transformation in vitro and induces tumors in newborn mice. Thus, A-raf represents a new proto-oncogene. Transformation by A-raf is independent of ras gene function, as is the case for raf and mos but not other oncogenes. 相似文献
104.
E Cayanis R Rajagopalan W L Cleveland I S Edelman B F Erlanger 《The Journal of biological chemistry》1986,261(11):5094-5103
A monoclonal antibody (8G11-C6) that is directed to a region near the ligand-binding site of the glucocorticoid receptor was obtained by an auto-anti-idiotypic route, using a derivative of triamcinolone coupled to thyroglobulin to immunize a mouse. The resulting hybridomas were screened for anti-idiotypic antibody (anti-antisteroid) with Fab fragments of affinity-purified polyclonal rabbit anti-triamcinolone antibody. The anti-idiotypes were then screened for binding to rat cytosol glucocorticoid receptor by a depletion procedure, yielding a clone, 8G11-C6, whose specificity for receptor was verified by sucrose density and Western blot analyses. Depletion was not significantly reduced by prelabeling the cytosol with [3H]triamcinolone acetonide. The anti-idiotype (8G11-C6) bound to Fab fragments of antisteroid and to partially purified receptor in a concentration-dependent manner. Both binding reactions were inhibited only by rabbit serum albumin conjugates of steroids known to bind to the glucocorticoid receptors. Triamcinolone derivatives of lysine and of oligopeptides containing up to six amino acids inhibited the binding of the anti-idiotype to the Fab fragments but not to the receptor, implying that the target epitope of the antisteroid antibody may be closer to its glucocorticoid-binding site than the cross-reacting epitope of the receptor. Our findings demonstrate further the versatility of the auto-anti-idiotypic route for the preparation of anti-receptor antibodies. 相似文献
105.
Multiple alpha and beta tubulin genes represent unlinked and dispersed gene families 总被引:17,自引:0,他引:17
D W Cleveland S H Hughes E Stubblefield M W Kirschner H E Varmus 《The Journal of biological chemistry》1981,256(6):3130-3134
Cloned cDNA sequences specific for alpha or beta tubulin mRNAs have been used to show that the multigene families which encode either alpha or beta tubulin are unlinked and dispersed throughout the chicken genome. Fractions of chicken chromosomes partially purified by centrifugation on a sucrose gradient were digested with restriction endonucleases and electrophoresed on agarose gels. The DNA was transferred to nitrocellulose filters and hybridized to labeled probes constructed from cloned cDNA sequences specific for alpha or beta tubulin. We find alpha tubulin sequences on four different chicken chromosomes and beta tubulin sequences on at least two different chromosomes. Moreover, using chicken chromosomes further purified with a fluorescent cell sorter, we have been able unambiguously to localize alpha tubulin genes to chromosome 1 and chromosome 8 and two of the beta genes to chromosome 2. 相似文献
106.
A divergent testis-specific alpha-tubulin isotype that does not contain a coded C-terminal tyrosine. 总被引:6,自引:2,他引:4 下载免费PDF全文
On the basis of analysis of cDNA clones of alpha-tubulin RNAs expressed during spermiogenesis in chickens, we report the identification of a novel alpha-tubulin which is expressed exclusively in chicken testes. Comparison of its sequence with those previously determined not only demonstrates that the encoded polypeptide is significantly divergent from other alpha-tubulins but also supports the hypothesis that alpha-tubulin isotypes are distinguished by a carboxy-terminal variable region sequence and, to a lesser extent, by a domain near the amino terminus. Since essentially all previously known alpha-tubulins undergo a unique cycle of removal and posttranslational readdition of a tyrosine residue at the extreme carboxy terminus, the presence in this testes alpha-tubulin of a very divergent carboxy terminus that does not contain an encoded tyrosine raises the possibility that this polypeptide does not participate in the usual cycle of tyrosination/detyrosination. 相似文献
107.
108.
Appearance of enzyme activities catalyzing conversion of sterigmatocystin to aflatoxin B1 in late-growth-phase Aspergillus parasiticus cultures. 总被引:10,自引:9,他引:1 下载免费PDF全文
Two activities involved in terminal pathway conversion of sterigmatocystin to aflatoxin B1 were isolated from an aflatoxin-nonproducing mutant of Aspergillus parasiticus (avn-1), and the time course of appearance of the activities in culture was determined. Subcellular fractionation of fungal mycelia resolved the two activities into a postmicrosomal activity which catalyzed conversion of sterigmatocystin to O-methylsterigmatocystin and a microsomal activity which converted O-methylsterigmatocystin to aflatoxin B1. The two activities were absent in 24-h-old cells, increased to optimum levels during the stationary phase, and then declined. 相似文献
109.
Tyrosine kinase oncogenes abrogate interleukin-3 dependence of murine myeloid cells through signaling pathways involving c-myc: conditional regulation of c-myc transcription by temperature-sensitive v-abl. 总被引:1,自引:1,他引:0 下载免费PDF全文
J L Cleveland M Dean N Rosenberg J Y Wang U R Rapp 《Molecular and cellular biology》1989,9(12):5685-5695
110.
Effect of lipoteichoic acid and lipids on lysis of intact cells of Streptococcus faecalis. 总被引:28,自引:17,他引:11 下载免费PDF全文
Autolysis of intact cells of Streptococcus faecalis was inhibited to a greater extent by phospholipids than by lipoteichoic acid, suggesting a possible difference in the accessibility of native autolysin to these substances. 相似文献