Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| the transforming function of bovine papillomavirus dna. | when bovine papillomavirus (bpv) or its 7.9-kilobase full viral dna genome induces focal transformation of mouse cells, the viral dna is maintained in the transformed cells as multiple episomal copies. this transforming capacity and maintenance of the episomal state previously has been localized to a 69% subgenomic fragment of the viral dna genome. we now have characterized further the bpv dna sequences that can encode the transforming function. we first created a series of bpv dna deletion muta ... | 1983 | 6310595 |
| construction and characterization of moloney murine leukemia virus mutants unable to synthesize glycosylated gag polyprotein. | murine leukemia virus (mulv) encodes two independent pathways for expression of the gag gene. one pathway results in processing and cleavage of the precursor pr65gag to yield the internal capsid proteins of the virion and is analogous to gag polyprotein precursors for all classes of retroviruses. the other pathway, which is not encoded by several other classes of retroviruses, begins with a glycosylated polyprotein gpr80gag . gpr80gag is synthesized independently of pr65gag; it contains pr65gag ... | 1983 | 6310608 |
| transforming growth factors released from kirsten sarcoma virus transformed cells do not compete for epidermal growth factor membrane receptors. | kirsten murine sarcoma virus (kimsv)-transformed rat kidney cells (knrk) release small polypeptides (mr 12,500-15,300) into the culture medium that are capable of stimulating normal rat kidney cells (nrk) to form colonies in soft agar. the transforming growth factors (tgfs) did not compete with epidermal growth factor (egf) for its receptor and did not induce specific phosphorylation of egf receptor on nrk cell membranes. these properties differ from the tgfs isolated by other investigators. our ... | 1983 | 6311845 |
| restriction of host range of xenotropic pseudotype murine sarcoma virus by helper leukemia virus. | we investigated the restriction of the host range to infectivity of msv by helper leukemia virus in vivo. when newborn sd-rats were inoculated intracerebrally, subcutaneously, intraperitoneally or intramuscularly with xenotropic pseudotype kirsten msv, ki-msv(bv2), either brain tumors or myogenic sarcomas were induced, depending upon the route of inoculation. however, no tumors developed in sw-icr mice inoculated with ki-msv(bv2) either intracerebrally or intramuscularly at birth. ecotropic ki-m ... | 1983 | 6312766 |
| inhibition of feline leukemia virus replication by human leukocyte interferon. | the replication of feline leukemia virus (felv) is inhibited by treatment of cat cell cultures with crude human leukocyte interferon (huifn-alpha) as evidenced by titration of the infectious progeny. the inhibition can be demonstrated in three different cell lines in which the production of hemagglutinin by encephalomyocarditis (emc) virus, and plaque formation by vesicular stomatitis virus (vsv) are also inhibited by the huifn-alpha. the dose dependency of the inhibition of emc virus by the hui ... | 1983 | 6312876 |
| host-specificities of papillomavirus, moloney murine sarcoma virus and simian virus 40 enhancer sequences. | the bovine papillomavirus (bpv-1), moloney murine sarcoma virus (momusv) and simian virus 40(sv40) genomes have been shown to contain sequences termed 'enhancers' which activate the expression of linked genes. dna fragments containing these three enhancers have been inserted into recombinant plasmids upstream from the herpes simplex virus thymidine kinase (tk) gene, and their effect on tk expression monitored. two types of assay have been used. firstly, the ability of recombinant plasmids to tra ... | 1983 | 6313355 |
| epidermal growth factor receptor metabolism and protein kinase activity in human a431 cells infected with snyder-theilen feline sarcoma virus or harvey or kirsten murine sarcoma virus. | when human a431 cells, which carry high numbers of epidermal growth factor (egf) receptors, are exposed to egf, the total content of phosphotyrosine in cell protein is increased, the egf receptor becomes phosphorylated at tyrosine, and new phosphotyrosine-containing 36,000- and 81,000-dalton proteins are detected. we examined the properties of a431 cells infected with snyder-theilen feline sarcoma virus, whose transforming protein has associated tyrosine protein kinase activity, and harvey and k ... | 1983 | 6313970 |
| glucocorticoids enhance viral transformation of mammalian cells. | the effect of glucocorticoids on the replication of murine sarcoma virus (msv) in mammalian cells were examined. glucocorticoids, hydrocortisone (1 to 10 micrograms/ml) and dexamethasone (5 micrograms/ml), enhance transformation induced by the kirsten strain of msv (ki-msv) in normal rat kidney and human cells 10- to 30-fold. the enhancing effect was much more pronounced in normal human colonic mucosal epithelial-like cells. on the other hand, the hormones estradiol, testosterone, and progestero ... | 1983 | 6314344 |
| syncytium-induction inhibition test with complement for detection of antibodies against bovine leukemia virus. | a modified syncytium-induction inhibition test which is more sensitive than the immunodiffusion test, was developed using rabbit complement. in this test, fetal lamb kidney cells continuously infected with bovine leukemia virus were used as effector cells, and the cc81 cat cells transformed with murine sarcoma virus, were used as indicator cells. the syncytium-induction inhibition effect of anti-bovine leukemia virus serum was enhanced significantly by the addition of rabbit complement. the sync ... | 1983 | 6315200 |
| dissociation between transformed and differentiated phenotype in rat thyroid epithelial cells after transformation with a temperature-sensitive mutant of the kirsten murine sarcoma virus. | differentiated rat thyroid epithelial cells, infected in vitro with a temperature-sensitive mutant of the kirsten murine sarcoma virus, expressed at the permissive temperature (33 degrees c) some phenotypic properties typical of transformed cells, including morphological features, colony formation in agar, and induction of tumors in newborn animals. specific functional markers of these differentiated cells, i.e., synthesis/secretion of thyroglobulin, synthesis of thyroglobulin mrna and iodide up ... | 1983 | 6318081 |
| ras-related gene sequences identified and isolated from saccharomyces cerevisiae. | the oncogenes of harvey and kirsten murine sarcoma viruses (v-rash and v-rask) and their cellular homologues (c-rash and c-rask) constitute two members of the ras gene family. each functional member of the ras gene family encodes a 21,000 molecular weight protein (p21ras). ras genes have been detected in a wide variety of vertebrate species, including xenopus laevis (r. e. steele, personal communication), and in drosophila melanogaster. we report here the detection of ras-related genes in the ye ... | 1983 | 6318116 |
| nucleotide sequences of feline sarcoma virus long terminal repeats and 5' leaders show extensive homology to those of other mammalian retroviruses. | the nucleotide sequences of the gardner-arnstein feline sarcoma virus (fesv) long terminal repeat and the adjacent leader sequences 5' to the viral gag gene were determined. these were compared with homologous portions of synder-theilen fesv and with previously published sequences for moloney murine sarcoma virus and simian sarcoma virus proviral dna. more than 75% of the residues in the fesv r and u5 regions were homologous to sequences within the same regions of the other viral long terminal r ... | 1983 | 6296453 |
| oncogene from human ej bladder carcinoma is located on the short arm of chromosome 11. | the human cellular homolog of the transforming dna sequence isolated from the bladder carcinoma cell line ej was localized on the short arm of human chromosome 11 by southern blot analysis of human-rodent hybrid cell dna. this locus contains human sequences homologous to the harvey murine sarcoma virus v-ha-ras oncogene. | 1983 | 6297001 |
| balb and kirsten murine sarcoma viruses alter growth and differentiation of egf-dependent balb/c mouse epidermal keratinocyte lines. | clonal balb/c mouse epidermal keratinocyte (balb/mk) cell lines were established in tissue culture. despite their aneuploid nature, the lines were nontumorigenic, and retained in vitro properties similar to those of primary diploid keratinocytes. these included the constitutive expression of keratin and terminal differentiation in response to a calcium concentration greater than 1.0 mm in the medium. the cells also demonstrated an absolute requirement for nanomolar concentrations of epidermal gr ... | 1983 | 6297803 |
| characterization of a human colon/lung carcinoma oncogene. | dna sequences capable of inducing oncogenic transformation of nih3t3 mouse cells are found in a number of human tumour cell lines. when dnas of these cell lines are applied to monolayer cultures of the mouse fibroblasts, foci of transformed cells are observed 2-3 weeks later. dna from cells of such primary foci can be used in turn to induce foci in a second cycle of gene transfer. the human dna sequences responsible for transformation have been called oncogenes, the best characterized of which i ... | 1983 | 6298638 |
| adoptive t cell immunotherapy of msv-induced tumours in nude mice. part i. biology of tumour regression and recurrence. | the induction of immunity to progressively growing murine sarcoma virus (msv) tumours in nude (nu/nu) mice by reconstitution with immune t cells from syngeneic (+/+) donors has been studied. whole spleen cell preparations served as the source of immune t cells. transfer of immune, but not of normal, spleen cells resulted in partial or apparently complete regression of primary tumours and a related moderate to considerable extension of survival time. the dose, the time in days between immunizatio ... | 1983 | 6100803 |
| adoptive t cell immunotherapy of msv-induced tumours in nude mice. part ii. sequential analysis of serum immune complexes and blocking activity in reconstituted mice in relation to tumour biology. | in seven separate experiments, nude (nu/nu) mice carrying established murine sarcoma virus (msv) tumours were reconstituted with syngeneic (+/+) immune splenic t cells. these immune protected mice were randomly divided to provide smaller groups for serial exsanguination. at various time points mice were individually bled and cic concentration and blocking activity of each individual serum was determined. control sera were obtained from nu/nu and adult +/+ mice inoculated with tumour cells only, ... | 1983 | 6100804 |
| high-level expression of oncogenes in escherichia coli. | a plasmid, pjl6, was constructed that contains a unique cla i site 12 codons beyond the bacteriophage lambda cii gene initiation codon, as well as an adjacent unique hind iii site. these sites allowed us to fuse the sequences from the avian myelocytomatosis virus (mc29) v-myc gene, the avian myeloblastosis virus (amv) v-myb gene, and the harvey murine sarcoma virus (ha-musv) v-ras gene to the amino-terminal portion of the cii gene. transcription of the hybrid genes is controlled from the lambda ... | 1983 | 6101025 |
| role of accessory cells in the induction of a secondary cytotoxic response to moloney murine sarcoma virus-induced tumors. | the role of ia-positive accessory cells in the generation of a secondary cytotoxic response to tumor-associated antigens induced by moloney murine sarcoma virus (m-msv) was evaluated. spleen cells from m-msv-immune a.tl mice, depleted of accessory cells by anti-iak serum plus c treatment and stimulated in secondary mixed leukocyte tumor cell culture (mltc) with syngeneic ia-negative a6atl moloney leukemic cells, failed to generate virus-specific cytotoxic t lymphocytes (ctl). ctl generation in i ... | 1983 | 6185589 |
| specific antigrowth effect of interferon on mouse cells transformed by murine sarcoma virus. | the growth rate of nih/3t3 mouse fibroblasts transformed by the moloney strain of murine sarcoma virus was investigated following interferon (ifn) treatment. these cells were found to be sensitive to the antigrowth effect of ifn as indicated by a slower growth rate in its presence. the effect was most efficiently expressed when cells were grown at low serum concentrations, e.g., 2.5%. likewise, ifn treatment caused a reduction in the rate of dna synthesis as measured by [3h]thymidine incorporati ... | 1983 | 6186372 |
| [role of interferon in the phenotypic reversion of transformed cells: loss of malignancy]. | transformation of cells by oncogenic rna viruses is related to a number of significant changes in cell morphology and functions. the most common features of transformed cells are essentially the decrease of cell adhesiveness and the loss of contact inhibition. these changes are probably associated with an alteration of the cytoskeleton together with a marked modification in the number and distribution of membrane and extracellular matrix components. balb/c embryonic fibroblasts transformed by mu ... | 1983 | 6190122 |
| the mechanism of interferon effect on cell transformation by murine sarcoma virus. | mouse interferon (ifn) was found to inhibit murine sarcoma virus (msv)-induced neoplastic transformation of normal rat kidney (nrk) cells. this effect was observed upon examining the formation of foci of morphologically altered cells and colonies of anchorage-independent cells. ifn had no cytotoxic effect on msv-transformed nrk cells, nor on their focus or colony-forming ability. it was therefore apparent that its inhibitory effect was directed against the viral role in cell transformation. in a ... | 1983 | 6190765 |
| presence of a kirsten murine sarcoma virus ras oncogene in cells transformed by 3-methylcholanthrene. | oncogenes have previously been reported in the dnas of mouse fibroblast lines which had become transformed after in vitro exposure to the carcinogen 3-methylcholanthrene. these oncogenes are now shown to be versions of the cellular kirsten ras gene and are therefore homologous to oncogenes detected in a variety of human tumor dnas. | 1983 | 6197628 |
| mutants of nonproducer cell lines transformed by murine sarcoma virus. iv. multiplicity of proviral sequences and persistent viral production. | 1983 | 6299995 | |
| a functional component of the sea urchin h2a gene modulator contains an extended sequence homology to a viral enhancer. | the dna sequences imparting a maximal rate of sea urchin h2a gene transcription in the frog oocyte nucleus were narrowed down by deletion mapping to a dna segment -165 to -111, far-upstream of the h2a mrna cap site. c to t base changes in this area create strong down mutations, hence the primary structure of this dna sequence is of paramount importance to the h2a gene expression. sequence comparisons suggest that the -165 to -111 region may contain two essential sequence blocks. most strikingly, ... | 1983 | 6324073 |
| p85gag-mos encoded by ts110 moloney murine sarcoma virus: rapid at the restrictive temperature. | the stability of p85gag-mos, encoded by ts110 moloney murine sarcoma virus, was studied. p85gag-mos was found to turn over more rapidly at 39 degrees c than 33 degrees c in two different cell lines. one of these is a non-producer cell clone (6m2) which appears only to express p85 at 33 degrees c. the other cell line (206-2ic) produces p85gag-mos at both 33 degrees c and 39 degrees c, although in lower amounts at the higher temperature. both cell lines exhibit the normal morphological phenotype f ... | 1983 | 6311952 |
| inhibition of retrovirus dna supercoiling in interferon-treated cells. | the effect of interferon (ifn) on the cytoplasmic synthesis of murine sarcoma virus dna, its transport to the host nucleus, and its integration into the cellular genome were investigated. for this purpose, at various intervals after infection. dna was extracted from the cytoplasmic fraction, nuclear hirt supernatant, and chromosomal dna pellet. the relative amount of viral dna was estimated by c0t kinetics analysis of hybridization to murine sarcoma virus-specific [3h]cdna. ifn was found to dela ... | 1983 | 6193285 |
| flat revertants isolated from kirsten sarcoma virus-transformed cells are resistant to the action of specific oncogenes. | two flat revertants have been isolated from mutagen-treated populations of kirsten murine sarcoma virus (ki-musv)-transformed nih/3t3 cells. these revertants, which appear to be cellular variants resistant to transformation by the ki-musv oncogene v-ki-ras, contain ki-musv-specific dna, elevated levels of the v-ki-ras gene product p21, and rescuable transforming virus. cell hybridization studies indicated that the revertant phenotype is dominant in hybrids between revertant cells and cells trans ... | 1983 | 6604274 |
| characterization of viral rna in cells transformed by various isolates of moloney murine sarcoma virus. | intracellular polyadenylated viral rna from cells infected by five different isolates of moloney murine sarcoma virus (mo-musv) was analysed by gel transfer hybridization. genomic sizes of 4.6 kilobases (kb) for the ml-musv isolate, 5.2 kb for the m3- and 124-musv, 6.1 kb for the htl-musv and 6.7 kb for the 78-al-musv were determined. with the exception of the ml strain, subgenomic rna species were found in cells infected by the various isolates. however, no common subgenomic rna containing v-mo ... | 1983 | 6310043 |
| synthesis and biological investigations of new tuftsin analogs with elongated peptide chain. | in this paper the synthesis of the following elongated tuftsin analogs: thr-lys-pro-lys-thr-lys-pro-lys (i), thr-lys-pro-lys-thr-lys-pro-arg (ii) and ala-lys-thr-lys-pro-arg-glu-gln (iii) by the classical method is described. the compound ii markedly inhibited the growth of murine sarcoma viruses (msv). | 1983 | 6311764 |
| ldhk, the lactate dehydrogenase associated with transformation by the kirsten sarcoma virus: a re-evaluation. | a lactate dehydrogenase isozyme designated "ldhk" has recently been described in cells transformed by the kirsten murine sarcoma virus. several unusual properties were felt to distinguish this ldh isozyme from previously described ldh isozymes. these properties include cathodic electrophoretic migration in acrylamide gels using an imidazole/borate buffer system, inhibition of activity by oxygen and gtp, and stimulation of activity by cyanide. however, this report demonstrates that the muscle-typ ... | 1983 | 6298208 |
| susceptibility of skin fibroblasts from patients with retinoblastoma to transformation by murine sarcoma virus. | cultured skin fibroblasts from patients with retinoblastoma (rb) of different etiology have been studied for their susceptibility to transformation by murine sarcoma virus. the cells from patients with a deletion in chromosome 13 (13q-) and those from sporadic unilateral cases due to somatic mutation were as sensitive as normal cells. however, the cells from familial cases showed an extremely high sensitivity to transformation. moreover, in familial cases the susceptibility was significantly hig ... | 1983 | 6299517 |
| an altered dna sequence encompassing the ras gene of harvey murine sarcoma virus. | the dna fragment encompassing the ras gene of harvey murine sarcoma virus was sequenced and assigned the coding region of a transforming protein, p21, to the sequence. examination of nucleotide sequence, taken together with the result of analysis of the ras mrnas (1), has revealed that p21 is encoded from a continuous coding region starting with the 5' proximal initiation codon but not a processed protein. however, there were found several differences between the sequence published by dhar et. a ... | 1984 | 6087292 |
| further genetic localization of the transforming sequences of the p21 v-ras gene of harvey murine sarcoma virus. | the sequences encoding the 21-kilodalton transforming protein (p21 ras) of harvey murine sarcoma virus have previously been localized genetically to a 1.3-kilobase segment of the viral dna (e. h. chang, r. w. ellis, e. m. scolnick, and d. r. lowy, science 210:1249-1251, 1980). within this segment, dna sequence analysis has found a single open reading frame large enough to encode the viral p21 (r. dhar, r. w. ellis, t. y. shih, s. oroszlan, b. shapiro, j. maizel, d. lowy, and e. m. scolnick, scie ... | 1984 | 6319763 |
| nucleotide sequence of the transforming gene of m1 murine sarcoma virus. | the v-mosm1 nucleotide sequence codes for a protein that is 376 amino acids long. although the n-terminus is homologous with that of the v-mos124 protein, the c-terminus is substantially different from the c-termini of all other examined mos proteins, suggesting that this region is nonessential and perhaps cleaved. overall, v-mosm1 has greater homology with c-mos than does v-mos124, but mutually exclusive differences between c-mos and each of the v-mos genes preclude linear descent and suggest a ... | 1984 | 6319757 |
| demonstration of virus particles in moloney murine sarcoma virus-induced periosteal bone in mice. | balb/c mice were inoculated intramuscularly with moloney murine sarcoma virus in one of the hind legs. this led to the rapid development of a regressive sarcoma and also to the proliferation and osteogenic differentiation of cells in the adjacent periosteum. examination of the tissues by transmission electron microscopy revealed the presence of type a and c virus particles within the sarcoma cells as well as within the cells of the newly formed bone. extracellular type c virus particles were for ... | 1984 | 6147919 |
| fbr murine osteosarcoma virus. i. molecular analysis and characterization of a 75,000-da gag-fos fusion product. | the fbr murine osteosarcoma virus complex induces bone tumors with a similar latency and pathology to those induced by the fbj virus complex. fbr murine sarcoma virus ( fbr -msv) has been isolated from its helper virus(es) by the establishment of transformed nonproducer cells. these cells were found to express a 75,000-da protein (p75) which was antigenically related to the p55 oncogene product of the fbj murine osteosarcoma virus ( fbj -msv). p75 also contained antigenic determinants of murine ... | 1984 | 6203214 |
| tyrosyl kinases acquired from anchorage-independent cells by a membrane-enveloped virus. | tyrosyl kinase activity in vesicular stomatitis virus (vsv) acquired from host cells that differ in morphology was investigated. vsv grown in baby hamster kidney (bhk) cells with rounded morphology and a high efficiency of colony formation in soft agar (rous sarcoma virus [rsv]-transformed and suspension bhk cells) was compared with vsv grown in bhk cells with a flattened morphology and lower efficiency of colony formation in soft agar (rsv-infected revertant and control bhk cells). tyrosyl kina ... | 1984 | 6206078 |
| transformation by murine sarcoma virus alters the sensitivity of clonal cells derived from nih/3t3 mouse fibroblasts to interferon. | in contrast to normal clonal cells (a5) derived from nih/3t3 mouse fibroblasts, another clone (a10) derived from the same source was found to be resistant to the anti-lytic-virus activity of ifn and to be deficient in the induction of (2'-5') oligoadenylate synthetase (2-5a synthetase) by ifn. following infection of either a5 or a10 cells with moloney murine sarcoma virus (msv), a few transformed colonies were isolated, expanded, and tested for their sensitivity to ifn. it is clearly demonstrate ... | 1984 | 6206644 |
| the p21 ras c-terminus is required for transformation and membrane association. | the harvey murine sarcoma virus (ha-musv) transforming gene, v-rash, encodes a 21,000 molecular weight protein (p21) that is closely related to the p21 proteins encoded by the cellular transforming genes of the ras gene family. the primary translation product (prop21), which is found in the cytosol, undergoes posttranslational modification and the mature protein subsequently becomes associated with the inner surface of the plasma membrane and binds lipid tightly. the p21 proteins have the capaci ... | 1984 | 6087162 |
| murine retrovirus pr65gag forms a 130k dimer in the absence of disulfide reducing agents. | gazdar-murine sarcoma virus (gz-msv) particles, obtained from tissue culture fluids of chronically infected htg-2 hamster cells are immature in morphology and contain uncleaved pr65gag as the predominant protein (greater than 95% coomassie blue stain) (a. pinter and e. deharven, 1979, virology 99, 103-110; y. yoshinaka and r. b. luftig, 1982, virology 118, 380-388). when gz-msv particles are disrupted in 1% sodium dodecyl sulfate (sds) and then analyzed by sds-polyacrylamide gel electrophoresis ... | 1984 | 6087546 |
| [isolation and characterization of retroviruses expressed in murine osteosarcomas induced by 90sr]. | the induction of osteosarcomas with 90sr in cf1 mice is associated with the expression of ecotropic type-c rna viruses devoid of sarcomatogenic activity. in contrast, the fbr murine osteosarcoma virus complex, isolated from a 90 sr-induced osteosarcoma of a x/gf mouse [m. finkel et al. (1)], causes the rapid appearance of osteosarcomas in newborn mice and transforms fibroblasts in vitro. the transforming capacity of fbr murine sarcoma virus has been associated as an oncogene homologous to v-fos. | 1984 | 6088003 |
| homologies between a brain-specific identifier (id) sequence and regions of harvey murine sarcoma virus and rous sarcoma virus genomes. putative role of identifier sequences in the tissue specificity of malignant transformation by rna tumor viruses. | as a step toward understanding of the tissue specificity of cellular transformation by rna tumor viruses were looked for the presence of a putative brain specific regulatory (identifier) sequence (c82b) in the genome of various oncornaviruses. the genomes of harvey murine sarcoma virus and rous sarcoma virus contain sequences flanking the viral oncogenes with greater than 80% and greater than 60% homology to c82b, respectively. we suggest that identifier sequences acquired by oncoviruses may det ... | 1984 | 6088289 |
| expression of normal and transforming h-ras genes in escherichia coli and purification of their encoded p21 proteins. | the h-ras gene of the balb murine sarcoma virus (balb-msv) was placed under the transcriptional control of the tightly regulated pl promoter of bacteriophage lambda in the expression vectors pev-vrf-1 and prc23. upon derepression of the pl promoter, large amounts (10-20% of total cellular protein) of the h-ras gene product p21 are synthesized in escherichia coli. we constructed three h-ras gene expression vectors, designated pjcl-h5, pjcl-e30, and pjcl-33. pjcl-h5 directs the synthesis of p21, a ... | 1984 | 6089191 |
| sequences in the long terminal repeats of the moloney murine sarcoma virus-124 genome which control transforming gene function. | the role of long terminal repeat (ltr) sequences in the efficient expression of moloney murine sarcoma virus (msv-124) transforming gene function was investigated. recombinant plasmids containing a single ltr positioned 3' of v-mos were subjected to sequential deletions, and the relative transforming efficiency of these recombinants was analyzed in the nih/3t3 transfection assay. recombinants lacking caat, tata, and poly(a) signals within the ltr were able to transform with an efficiency compara ... | 1984 | 6089418 |
| modulation of enhancer activity by the hormone responsive regulatory element from mouse mammary tumor virus. | addition of the transcriptional enhancers present in the u3 region of the harvey murine sarcoma virus (hamusv) long terminal repeat (ltr) to recombinant chimeras in which the hamusv transforming gene (ha-v-ras) is expressed from the mouse mammary tumor virus (mmtv) promoter increases the ability of the mmtv v-ras chimeras to transform mouse fibroblasts in culture 50- to 100-fold. significant stimulation of transfection efficiency occurs only when glucocorticoids are present in the culture medium ... | 1984 | 6090130 |
| flat revertants derived from kirsten murine sarcoma virus-transformed cells produce transforming growth factors. | two flat cellular revertant cell lines, f-2 and c-11, which were originally selected from the dt line of kirsten murine sarcoma virus (ki-musv)-transformed nih/3t3 cells, were examined for the production of transforming growth factors (tgfs). the revertant cells fail to grow in semisolid medium as colonies and exhibit a markedly reduced level of tumorigenicity in nude mice, although they are known to express high levels of p21ras, the product of the kirsten sarcoma virus oncogene, ras, and they ... | 1984 | 6090475 |
| genesis of kirsten murine sarcoma virus: sequence analysis reveals recombination points and potential leukaemogenic determinant on parental leukaemia virus genome. | the genome of kirsten murine sarcoma virus was formed by recombination between kirsten murine leukaemia virus sequences, and rat sequences derived from a retrovirus-like '30s' (vl30) genetic element encompassing the kras oncogene. using cloned dnas we have determined the nucleotide sequences of the long terminal repeats and adjacent regions, extending across the points of recombination on the sarcoma and leukaemia virus genomes. our results suggest that discrete regions of homology and other cry ... | 1984 | 6091040 |
| use of the mouse mammary tumor virus long terminal repeat to promote steroid-inducible expression of v-mos. | we used the mouse mammary tumor virus long terminal repeat to promote dexamethasone-regulated expression of the moloney murine sarcoma virus (m-msv) transforming gene, v-mos. a recombinant dna vector containing the mouse mammary tumor virus long terminal repeat fused to the m-msv 124 v-mos gene was cotransfected with a plasmid containing the herpes simplex virus thymidine kinase gene (tk) into 3t3tk- cells. individual clones of cells which grew in hypoxanthine-aminopterin-thymidine medium were t ... | 1984 | 6092668 |
| metabolic turnover of human c-rash p21 protein of ej bladder carcinoma and its normal cellular and viral homologs. | the ej bladder carcinoma oncogene is activated by a point mutation in the c-rash proto-oncogene at the 12th amino acid codon. in an attempt to understand the mechanism of oncogenic activation, a comparative study was undertaken to examine the metabolic turnover and subcellular localization of the p21 protein encoded by the ej oncogene, the viral oncogene, and its normal cellular homolog. pulse-labeling experiments indicated that both c-ras p21 proteins were synthesized by a very similar pathway, ... | 1984 | 6092927 |
| biological properties of human c-ha-ras1 genes mutated at codon 12. | vertebrate genomes contain proto-oncogenes whose enhanced expression or alteration by mutation seems to be involved in the development of naturally occurring tumours. these activated genes, usually assayed by their ability to induce the malignant transformation of nih 3t3 cells, are frequently related to the ras oncogene of harvey (ha-ras) or kirsten (ki-ras) murine sarcoma viruses, or a third member of this family (n-ras). activation involves point mutation which often affect codon 12 (refs 16- ... | 1984 | 6092966 |
| expression of the onc gene of the kirsten murine sarcoma virus in differentiated rat thyroid epithelial cell lines. | a systematic study has been performed using a series of differentiated rat thyroid epithelial cell lines either uninfected or infected with kirsten murine sarcoma virus (kimsv), to determine the levels of the p21 product of the v-ras-ki oncogene in transformed and normal cell lines. the p21 levels have been assayed by sds-polyacrylamide gel electrophoresis of immunoprecipitates of 35s-labelled cell extracts and by a gdp binding assay. all cell lines analysed showed a significant increase in the ... | 1984 | 6094710 |
| the long terminal repeat of an endogenous intracisternal a-particle gene functions as a promoter when introduced into eucaryotic cells by transfection. | we describe experiments designed to determine whether an endogenous intracisternal a-particle (iap) gene randomly selected from a mouse embryo library has the potential to be transcriptionally active. assays for iap gene transcription were done with permanently transformed rat cells and transiently transfected monkey and mouse cells. the rat cells, which had integrated iap gene copies, contained iap rna. a start site within the iap 5' long terminal repeat (ltr) was localized by s1 mapping. the p ... | 1984 | 6095042 |
| introduction of a selectable gene into different animal tissue by a retrovirus recombinant vector. | the potential use of retrovirus vectors to transduce foreign genetic information into cells of different tissues of an animal was explored by introducing a recombinant genome carrying the eco gpt gene into postimplantation mouse embryos. to obviate the need for preparing concentrated virus stocks, psi 2-2-5 cells producing the replication-defective murine sarcoma virus (msv)-gpt virus were microinjected directly into embryos. the psi 2-2-5 cells were mixed with cells producing replication-compet ... | 1984 | 6095271 |
| harvey murine sarcoma virus p21 ras protein: biological and biochemical significance of the cysteine nearest the carboxy terminus. | previous studies of premature chain termination mutants and in frame deletion mutants of the p21 ras transforming protein encoded by the transforming gene of harvey murine sarcoma virus (ha-musv) have suggested that the c terminus is required for cellular transformation, lipid binding, and membrane localization. we have now further characterized the post-translational processing of these mutants and have also studied two c-terminal v-rash point mutants: one encodes serine in place of cysteine-18 ... | 1984 | 6096132 |
| the gag-mos hybrid protein of ts110 moloney murine sarcoma virus: variation of gene expression with temperature. | a nrk cell clone (6m2 cells) infected with ts110 moloney murine sarcoma virus (musv) produce a gag-mos protein, p85gag-mos, and a truncated gag protein of mr 58,000d termed p58gag. the gag-mos protein is produced from a 3.5-kb mrna whereas the gag protein is made from a 4.0-kb mrna. it has been proposed that the 3.5-kb rna is produced from the 4.0-kb rna by a splicing mechanism (r. p. junghans, e. c. murphy, jr., and r. b. arlinghaus (1982) j. mol. biol. 161, 229-255). the results presented here ... | 1984 | 6097031 |
| brain tumors in hamsters induced by murine sarcoma virus (moloney). | murine sarcoma virus, cs-moloney substrain, was inoculated intracranially into 2 litters of newborn syrian hamsters within 24 h of birth. seven of 12 hamsters which survived more than 30 days developed brain tumors in the cerebral cortex 104 to 153 days, 139 days on the average, after the virus inoculation. the tumors consisted of spindle-shaped, round or polygonal astrocytes which showed a positive reaction for glial fibrillary acidic protein by the immunoperoxidase method. | 1984 | 6097099 |
| efficient expression of cloned complementary dnas for secretory proteins after injection into xenopus oocytes. | cloned complementary dnas encoding chicken ovalbumin, chicken prelysozyme and calf preprochymosin, prochymosin and chymosin were inserted downstream from various viral promoters in modified recombinant "shuttle" vectors. microinjection of the ovalbumin, prelysozyme and preprochymosin constructs into the nuclei of xenopus laevis oocytes resulted in the synthesis, segregation in membranes and secretion into the extracellular medium of ovalbumin, lysozyme and prochymosin, respectively. judging from ... | 1984 | 6098686 |
| immunity against moloney sarcoma virus in h-2db mutant bm14 mice. unimpaired tumor immunity despite absence of a virus-specific cytotoxic t-cell response. | it was shown previously that b6.c-h-2bm14 (bm14) mice, carrying a mutation in the h-2db locus, are unable to generate cytotoxic t cells (ctl) against moloney murine sarcoma virus (m-msv). we now report an analysis of tumor induction and regression kinetics and of immunity to the virus, following the injection of graded doses of m-msv into c57bl/6 (b6) and bm14 mice. contrary to expectation, bm14 mice showed slightly less tumors than wildtype b6 mice. moreover, all bm14 mice that developed a tumo ... | 1984 | 6319305 |
| integration of proviral dna in kirsten murine sarcoma virus-infected mouse fibroblasts. | the structure and sites of integration of proviral dna were studied in 19 clonally related kirsten murine sarcoma virus-transformed non-producer nih/3t3 cell lines. the majority of these cell lines contained a single provirus, inserted colinearly with respect to unintegrated linear viral dna, and lacking detectable methylation at mspi/hpaii sites. although all proviruses were located at distinct integration sites in the host cell genome, the possible existence of similarities between some adjace ... | 1984 | 6319576 |
| homologous cell-derived oncogenes in avian carcinoma virus mh2 and murine sarcoma virus 3611. | retroviral oncogenes (v-onc) are derived from cellular genes (c-onc) which are highly conserved among different species. retrovirus-transduced oncogenes are most commonly associated with the induction of haematopoietic tumours and sarcomas. the avian retrovirus mill hill no. 2 (mh2) was isolated from a spontaneous ovarian tumour of a chicken and is distinguished by the predominant induction of liver and kidney carcinomas in fowl. mh2 also induces transformation of fibroblasts, macrophages and ep ... | 1984 | 6319999 |
| chromosome assignments of four mouse cellular homologs of sarcoma and leukemia virus oncogenes. | molecular probes for the oncogenes of rous sarcoma virus (v-src), avian myeloblastosis virus (v-myb), kirsten murine sarcoma virus (v-ki-ras), and harvey murine sarcoma virus (v-ha-ras) were hybridized to the dna from mouse-chinese hamster somatic cell hybrids. the v-src, v-myb, v-ki-ras, and v-ha-ras genes each detected one or a few homologous mouse dna fragments whose segregation was analyzed in cell hybrids. mouse cellular homologs c-src, c-ki-ras, c-ha-ras, and c-myb segregated concordantly ... | 1984 | 6320193 |
| a common onc gene sequence transduced by avian carcinoma virus mh2 and by murine sarcoma virus 3611. | a common cellular sequence was independently transduced by avian carcinoma virus mh2 (v-mht) and murine sarcoma virus (msv) 3611 (v-raf). comparison of the nucleotide sequences of v-mht and v-raf revealed a region of homology that extends over 969 nucleotides. the homology between the corresponding amino acids was about 95 percent with only 19 of 323 amino acids being different. with this example, 5 of the 19 known different viral onc genes have been observed in viruses of different taxonomic gr ... | 1984 | 6320371 |
| development of serum independence in kirsten murine sarcoma virus-infected rat adrenal cells. | cells cultured from explants of adult rat adrenal cortex are spindle shaped and divide rapidly in media with 10-25% fetal bovine serum (fbs), but are epithelial-like and stationary in 3-6% horse serum (hs). fully transformed kirsten murine sarcoma virus (kimsv)-infected cells lose this differential response to serum. to determine at what stage in the transformation process this loss occurs, cultures in passages 1-2 were infected with kimsv, propagated for up to 30 weeks in fbs, and parallel cult ... | 1984 | 6321049 |
| regulation of b cell lymphomagenesis by a malignant qal+ inducer t cell clone. | a series of thy-1.2+ ly-1+ qa-1+ malignant t cell clones have been isolated from murine sarcoma virus-murine leukemia-moloney (msv-mulv-m)-induced b cell lymphomas or from msv-mulv-m-infected b6 mice. these t cell clones enhance both antigen-independent and -dependent lymphocyte differentiation and function. they also induce the differentiation of granulocytes and erythrocytes in the stem cell compartment, a function that parallels the immunopathology of the disease in vivo. the malignant t cell ... | 1984 | 6321629 |
| restriction of moloney murine leukemia virus replication in moloney murine sarcoma virus-infected cells. | musv349 is a tb-cell line which produces infectious musv with little or no mulv detectable by the xc assay. the apparent restriction of mulv replication in musv349 cells was investigated. a replication-competent helper virus, with protein composition nearly identical to that of mo-mulv was isolated from the viruses produced by musv349 cells. this helper mulv after it was separated from musv and upon infection of tb cells produced viral titer similar to that of mo-mulv-infected tb cells indicatin ... | 1984 | 6322420 |
| isolation and characterization of a mo-musv-transformed tb cell line that produces noninfectious musv particles with uncleaved gag protein which is processed in the presence of mo-mulv. | a cell line, tbsv7, that produces noninfectious murine sarcoma virus (musv) in the absence of helper mulv was isolated from tb cells infected with the supernatant of musv349 cells. these noninfectious musv particles with "immature" c-type virus morphology contain a 2.2 x 10(6)-da genomic rna and an uncleaved 62,000-da gag precursor protein (pr62). neither viral envelope proteins (gp70, p15e, p12e) nor reverse transcriptase were detected in these virus particles. pr62 was found to be phosphorylat ... | 1984 | 6322421 |
| incorporation of lipids into variants of moloney sarcoma virus which produce gag-mos fusion proteins. | several transforming gene products of mammalian retroviruses undergo post-translational addition of fatty acids. this report demonstrates that gag-mos fusion proteins from variant strains of murine sarcoma viruses incorporate both myristate and palmitate. however, the inefficiency of palmitate incorporation, as well as incorporation of that fatty acid into gag proteins, suggest that palmitate is metabolized to myristate before becoming bound to virus proteins. furthermore, no detectable post-tra ... | 1984 | 6322433 |
| characterization and cloning of the kirsten murine leukemia virus genome. | we have characterized the intracellular and circular unintegrated proviral dna species of kirsten murine leukemia virus by restriction mapping using the southern blotting technique. these studies show the 8.5 kilobase pair genome to possess long terminal repeats (0.5 kilobase pairs in length) which are indistinguishable from those of the derivative kirsten murine sarcoma virus. in addition, we have identified a 3'-located region in kirsten murine leukemia virus which is very similar to the putat ... | 1984 | 6322772 |
| photoaffinity labeling with gtp of viral p21 ras protein expressed in escherichia coli. | the v-ras oncogene of harvey murine sarcoma virus encodes a 21,000-dalton protein, p21, which mediates transformation produced by that virus. previous work has shown that both p21v-rash and the cellular homolog p21c-rash appear to bind guanine nucleotides. we report here the expression in escherichia coli of v-rash to produce a biochemically active p21 fusion protein which retains both guanine nucleotide binding and autophosphorylating activity. furthermore, direct interaction of this protein wi ... | 1984 | 6323735 |
| expression of kirsten murine sarcoma virus in transformed nonproducer and revertant nih/3t3 cells: evidence for cell-mediated resistance to a viral oncogene in phenotypic reversion. | expression of the provirus in a clonally related series of kirsten murine sarcoma virus-transformed nih/3t3 nonproducer cell lines was examined at both the transcriptional and translational levels. all cells expressed high levels of genome-sized viral rna with little variation between cell lines despite differences in provirus integration site and copy number. expression of k-ras rna was estimated to be at least 10- to 20-fold higher than that of the mouse cellular homolog of the viral transform ... | 1984 | 6323744 |
| s1 nuclease mapping of viral rnas from a temperature-sensitive transformation mutant of murine sarcoma virus. | the structures of murine sarcoma virus (musv) ts110 viral rna and intracellular rna present in musv ts110-infected cells (6m2 cells) have been examined by s1 nuclease analysis. a previous study involving heteroduplex analysis of musv ts110 viral rnas hybridized to wild-type dna revealed the presence of two musv ts110 rnas, 4.0 and 3.5 kilobases (kb) in length, containing overlapping central deletions relative to wild-type musv 124 viral rna (junghans et al., j. mol. biol. 161:229-255, 1982). her ... | 1984 | 6323748 |
| primary structure of v-raf: relatedness to the src family of oncogenes. | a replication-defective, acute transforming retrovirus (murine sarcoma virus 3611) was isolated from mouse and molecularly cloned. the nucleotide sequence of 1.5 kilobases encompassing the transforming gene (v-raf) was determined. this sequence, which predicts the amino acid sequence of a gag-raf fusion protein, terminates 180 nucleotides from the 3' end of the acquired cellular sequence. comparison of the predicted amino acid sequence of v-raf with the predicted amino acid sequences of other on ... | 1984 | 6324342 |
| role of infectious virus expression and immune response in retrovirus-induced oncogenesis. | some of the parameters involved in retrovirus-induced oncogenesis were analyzed in newborn mice injected with moloney-murine leukemia virus (m-mulv) as well as in adults who received the virus by the intraperitoneal (i.p.) or intrathymic (i.t.) route. the neonatally injected mice were permissive for both viral replication and virus-induced cell-surface antigen expression on thymus cells, peripheral t and b lymphocytes, and macrophages, whereas the m-mulv was not present in the adult i.p. injecte ... | 1984 | 6324431 |
| an unusual oxygen-sensitive lactate dehydrogenase isozyme associated with kirsten murine sarcoma virus in human serum. | an unusual isozyme of lactate dehydrogenase, lactate dehydrogenase associated with kirsten murine sarcoma virus (ldhk) was found in the sera of many patients with malignant tumors, while the sera of healthy persons had little or no such activity. this isozyme was detectable only when assayed in a nitrogen atmosphere, and its activity showed little or no relationship to the total lactate dehydrogenase activity as measured by a standard clinical assay. the activity of serum ldhk appeared to be cor ... | 1984 | 6325000 |
| characterization of a human transforming gene isolated from t24 bladder carcinoma cells. | a human transforming gene present in t24 bladder carcinoma cells has been molecularly cloned. the transforming sequences have been located within a 4.6 kilo base pair (kbp) dna fragment that transforms nih/3t3 cells with a specific activity of 5 x 10(4) focus-forming units/pmol. homologous sequences present in normal human dna have also been molecularly cloned. comparison of the restriction endonuclease maps of the normal and transforming genes did not reveal any significant differences. these r ... | 1984 | 6325252 |
| production of platelet-derived growth factor-like molecules and reduced expression of platelet-derived growth factor receptors accompany transformation by a wide spectrum of agents. | a series of nontransformed human and murine cells and derivative cell lines transformed by methylcholanthrene; by simian virus 40, kirsten and moloney murine sarcoma viruses, simian sarcoma virus, and adenovirus; and by a "spontaneous" event in culture were examined for the expression of receptors for the platelet-derived growth factor (pdgf) and for production of substances able to compete with 125i-labeled pdgf for binding to the cell-surface pdgf receptor. in each case, transformation resulte ... | 1984 | 6326125 |
| molecular cloning and characterization of a leukemia-inducing myeloproliferative sarcoma virus and two of its temperature-sensitive mutants. | the myeloproliferative sarcoma virus (mpsv) induces extensive hematopoietic changes, including spleen foci in adult mice, and transforms fibroblasts in vitro. nrk nonproducer cell lines of mpsv and ts temperature-sensitive mutants were analyzed by restriction enzyme digestion and southern blotting. ecori fragments containing the proviral dnas of mpsv and two temperature-sensitive mutants and rat cellular sequences homologous to c-mos were molecularly cloned. by comparing restriction enzyme cleav ... | 1984 | 6328001 |
| comparison of myeloproliferative sarcoma virus with moloney murine sarcoma virus variants by nucleotide sequencing and heteroduplex analysis. | the myeloproliferative sarcoma virus (mpsv) was derived by passage of moloney sarcoma virus (mo-musv) in adult mice. mo-musv variants transform fibroblasts. however, mpsv also affects erythroid, myeloid, and hematopoietic stem cells. the mpsv proviral genome, two temperature-sensitive mutants derived from it, mo-musv variant m1, and moloney murine leukemia virus (mo-mulv) were compared by heteroduplex mapping. mpsv wild type was found to have 1 kilobase pair deleted from the pol gene and to cont ... | 1984 | 6328002 |
| expression of xenotropic-like env rna sequences in normal dba/2 and nzb mouse tissues. | using a dna probe prepared from cloned env gene sequences of friend spleen focus-forming viruses, we detected the differential expression of multiple rna species in uninfected dba/2 fibroblasts and in various tissues from adult dba/2 and nzb mice. the size of the major rna species detected was estimated to be 24s . the 24s rna species was enriched in polyadenylate-selected preparations and thus may represent a message for endogenous viral envelope glycoproteins. the viral origin of the 24s rna w ... | 1984 | 6328045 |
| ha-ras oncogenes are activated by somatic alterations in human urinary tract tumours. | dna-mediated gene transfer (transfection) studies using nih 3t3 cells as recipients have demonstrated the presence of transforming genes (oncogenes) in diverse human tumours. a large proportion of oncogenes so far detected by dna transfection are related to the ha-ras onc gene of harvey (and balb) murine sarcoma viruses (msv), ki-ras, the oncogene of kirsten msv, and a third member of the ras gene family, n-ras. individual tumours of many different organs have been associated with the activation ... | 1984 | 6328318 |
| nucleotide sequence of avian carcinoma virus mh2: two potential onc genes, one related to avian virus mc29 and the other related to murine sarcoma virus 3611. | the 5.2-kilobase (kb) rna genome of avian carcinoma virus mh2 has the genetic structure 5'-delta gag (0.2 kb)- mht (1.2 kb)-myc (1.4 kb)-c (0.4 kb)-poly(a) (0.2 kb)-3'. delta gag is a partial retroviral core protein gene, mht and myc are cell-derived mh2-specific sequences, and c is the 3'-terminal retroviral vector sequence. here we have determined the nucleotide sequence of 3.5 kb from the 3' end of delta gag to the 3' end of molecularly cloned proviral mh2 dna, in order to elucidate the genet ... | 1984 | 6328485 |
| loss of epidermal growth factor receptor on the renal neoplasm induced in vivo with xenotropic pseudotype kirsten murine sarcoma virus. | a characteristic feature of normal rat kidney (nrk) cells in their ability to bind epidermal growth factor (egf) and loss of the ability to bind egf in the renal neoplasm induced in vivo with c type rna virus were demonstrated. maximal binding capacity and apparent dissociation constant of nrk cells were 3.36 femtomoles of egf bound per 10(6) cells and 2.85 x 10(-11) m, respectively. the binding of egf to transformed cell in vivo with xenotropic pseudotype kirsten murine sarcoma virus was abolis ... | 1984 | 6329188 |
| in vitro transformation by bovine papillomavirus. | we have studied tumorigenic transformation of mouse tissue culture cells by bovine papillomavirus (bpv) as a model of papillomavirus-induced cell proliferation. when bpv or its 7.9-kb full-length viral dna genome induces focal transformation of mouse calls, the viral dna is maintained in the transformed cells as multiple extrachromosomal copies. the transforming capacity was initially localized to a 69% subgenomic fragment of the viral dna genome. we have further characterized the bpv dna sequen ... | 1984 | 6330216 |
| studies with inhibitors of oligosaccharide processing indicate a functional role for complex sugars in the transport and proteolysis of friend mink cell focus-inducing murine leukemia virus envelope proteins. | the functions of asparagine-linked oligosaccharides on the prenv protein of friend mink cell focus-inducing (frmcf-1) murine leukemia virus were investigated by examining the effect of two inhibitors of different stages of the biosynthetic pathway of these sugar substituents on the synthesis and processing of the viral proteins. treatment of virus-producing cells with tunicamycin totally inhibited the glycosylation of prenv, and resulted in the formation of a nonglycosylated form of the protein ... | 1984 | 6330991 |
| effects of retinoids on the proliferation of murine sarcoma virus-transformed cells in serum-free culture: potentiation of autocrine stimulation. | in a recent report, we described a growth stimulatory effect of vitamin a derivatives (retinoids) on murine sarcoma virus (msv)-transformed cell lines when tested in a serum-free culture condition. these cell lines were presumed to proliferate via autostimulatory (autocrine) mechanism when serum was omitted from culture medium. in the present communication, we examined the effect of 6 synthetic derivatives on the serum-free proliferation of 2 msv-transformed cell lines. we confirmed essentially ... | 1984 | 6331634 |
| tolerance to viral antigens in mov-13 mice carrying endogenized moloney-murine leukemia virus. | in virus-positive (v+) c57bl/6 mov-13 mice, moloney-murine leukemia virus (m-mulv) is integrated into the germ line and expressed early in lymphoid and nonlymphoid organs. the pattern of immune reactivity to viral antigens in these mice was studied and compared to that of their virus-negative (v-) counterparts. using a radioimmuno-binding or -precipitation assay, v- mice showed good antibody production after challenge with moloney-murine sarcoma virus (m-msv), but no antibodies were detected in ... | 1984 | 6607132 |
| autophosphorylation of v-ha-ras p21 is modulated by amino acid residue 12. | the 21,000-dalton protein (p21) encoded by the ras oncogene of harvey murine sarcoma virus (v-ha-ras) becomes phosphorylated (pp21) in vivo and in vitro on threonine residue 59. p21 molecules encoded by cellular ras genes (c-ha-ras-1) contain an alanine at position 59, and thus these p21 molecules are not phosphorylated. in this investigation, recombinant ras genes have been constructed between the 5' p21 coding region of normal (ec) or oncogenically activated (ej) human c-ha-ras-1 and the 3' p2 ... | 1984 | 6609366 |
| transformation of nih 3t3 cells by microinjection of ha-ras p21 protein. | alteration in gene structure has been shown to occur in some human tumours. these altered genes, termed oncogenes, were originally identified by their ability to induce foci of transformed cells on transfected mouse 3t3 cultures. the oncogene identified in the ej/t24 human bladder carcinoma is similar to the transforming gene of balb and harvey murine sarcoma virus (msv) and differs from its counterpart in normal cells by a single amino acid. all three of these ha-ras genes direct the production ... | 1984 | 6611509 |
| a molecular approach to leukemogenesis: mouse lymphomas contain an activated c-ras oncogene. | by inducing mouse thymomas with carcinogens and gamma-radiation, we have studied the potential of tumor dna to induce foci in rodent fibroblasts. a high percentage of the tumors used transformed the cultured cells, and the oncogenic phenotype segregated with extra copies of the c-ras gene family. there appears to be selectivity in the activated gene because so far all analyzed tumors induced by carcinogen have activated the n-ras gene, and those induced by radiation have activated the k-ras gene ... | 1984 | 6582476 |
| frequent generation of nonrescuable reorganized moloney murine sarcoma viral genomes. | nonproducer transformants infected with wild-type moloney murine sarcoma virus were screened for the generation of variants with reorganized genomes. seven of 20 lines contained such viral genomes, 5 of which were found to be nonrescuable. blotting analysis indicated that viral rna molecules transcribed from these variant genomes could not be encapsidated into virions. the nonrescuable genomes were molecularly cloned and all were found to have suffered deletions or deletions/inversions involving ... | 1984 | 6582487 |
| expression and characterization of ras mrnas from saccharomyces cerevisiae. | the cellular homologs of the harvey and kirsten murine sarcoma virus oncogenes comprise a multigene family, ras, that displays striking evolutionary conservation. we recently reported [defeo-jones et al., nature (london) 306:707-709, 1983] the cloning of two ras homologs from the yeast saccharomyces cerevisiae. the nucleotide sequences of these genes predict polypeptides that show remarkable homology to p21, the mammalian ras gene product. we have also found proteins in yeast lysates with serolo ... | 1984 | 6392849 |
| saccharomyces cerevisiae synthesizes proteins related to the p21 gene product of ras genes found in mammals. | a family of normal vertebrate genes and oncogenes has been called the ras gene family. the name ras was assigned to this gene family based on the species of origin of the viral oncogenes of the rat-derived harvey and kirsten murine sarcoma viruses. there are now three known functional members of the ras gene family, and genes homologous to ras genes have been detected in the dna of a wide variety of mammals and in drosophila melanogaster. prior experiments have detected proteins coded for by ras ... | 1984 | 6422257 |
| host-mediated antitumor activity of lactobacillus casei in mice. | antitumor activity of lactobacillus casei yit 9018 ( lc9018 ) was studied in balb/c mice by using two syngeneic tumors; methylcholanthrene-induced tumor (meth a fibrosarcoma) and kirstein murine sarcoma virus-transformed balb/3t3 ( k234 tumor). administration of an lc9018 -meth a cell mixture induced complete suppression of the tumor growth, while simultaneous injections of lc9018 and meth a cells into different sites had no suppressive effect on the tumor growth. administration of the mixture s ... | 1984 | 6427051 |
| comparison of antitumor activity of lactobacillus casei with other bacterial immunopotentiators. | antitumor activity of lactobacillus casei yit 9018 (lc9018) was demonstrated by intralesional (i.l.) or intravenous (i.v.) administration into tumor-bearing mice which were inoculated with methylcholanthrene-induced fibrosarcoma (meth a) or kirsten murine sarcoma virus-transformed tumor (k234) cells. its activity was significantly superior to the activity of two other species of lactobacilli but was nearly the same as that of corynebacterium parvum or mycobacterium bovis bacille calmette-guérin ... | 1984 | 6438456 |
| serine- and threonine-specific protein kinase activities of purified gag-mil and gag-raf proteins. | retroviruses carry cell-derived oncogenes (v-onc) that have the potential to transform cells in culture and induce tumours in vivo. one of the few carcinoma-inducing viruses is the acutely transforming retrovirus mh2, which carries the putative oncogene v-mil and the known oncogene v-myc. recently, a high degree of homology was discovered between v-mil and v-raf, the transforming gene of the murine retrovirus 3611 murine sarcoma virus (msv), whereas homology to v-src is low. both viruses express ... | 1984 | 6438534 |
| guanosine nucleotide binding by highly purified ha-ras-encoded p21 protein produced in escherichia coli. | high-level expression of the p21 protein product of the balb murine sarcoma virus v-ras gene (similar to the product of the harvey murine sarcoma virus v-ha-ras gene) has been reported recently, and highly purified preparations of this protein have been obtained. we used a nitrocellulose filter assay for measuring the binding of gdp and gtp to the purified protein. previously p21 antibodies had been used to precipitate p21-guanosine nucleotide complexes from crude extracts containing the protein ... | 1984 | 6438627 |
| temperature-dependent transmembrane potential changes in cells infected with a temperature-sensitive moloney sarcoma virus. | normal rat kidney cells (nrk) infected with the temperature-sensitive (ts) transformation mutant of moloney murine sarcoma virus yielded a clone of cells, 6m2, that exhibited a transformed morphology at 33 degrees c and a normal morphology at 39 degrees c. transmembrane potential (em) was measured fluorometrically using a cyanine dye dis-c3-(5). fluorescence was inversely correlated with em. cells at 33 degrees c had lower em. em changes were recorded within 15 minutes of temperature shift from ... | 1984 | 6480709 |
| murine sarcoma virus-induced brain tumors. concurrent measurements of blood flow and transcapillary transport. | intracerebral inoculation of murine sarcoma virus (msv) into rats induces highly vascular brain tumors. blood flow, f, and a unidirectional blood-to-tissue transfer constant, k, were measured concurrently in 16 separate brain tumors in 13 rats. regional measurements of f and k were obtained using double-label quantitative autoradiography with 131i-iodoantipyrine, 14c-alpha aminoisobutyric acid, and computerized microdensitometry with image analysis. regional tissue extraction fractions (e) were ... | 1984 | 6530618 |
| effect of anticancer drugs on renal neoplasm induced with xenotropic pseudotype kirsten murine sarcoma virus. | the sensitivity of a renal neoplasm induced in vivo with c type rna virus to anticancer drugs was evaluated. the proliferation rate of the virus induced neoplasm cells depended on the concentrations of antimetabolites, alkylates and antibiotics, but not depends on that of alkaloids. an inhibitory effect of drugs on the virus induced neoplasm cells became evident in the following order, i.e., antimetabolites, alkylates, antibiotics and then alkaloids. | 1984 | 6542874 |