Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| characterization of enhancer elements in the long terminal repeat of moloney murine sarcoma virus. | a series of recombinant molecules were constructed which direct the expression of the easily assayed gene chloramphenicol acetyltransferase. we have used these recombinants to show that the 73/72-base-pair tandem repeat unit from the moloney murine sarcoma virus long terminal repeat shares a number of properties with the prototypic enhancer element, the simian virus 40 72-base-pair repeat. specifically, the moloney murine sarcoma virus sequence significantly enhances the level of gene expression ... | 1984 | 6690710 |
| transformation of cultured epithelial cells by ethylnitrosourea. altered expression of type i procollagen chains. | cultured epithelial rodent cells were transformed in vitro using ethylnitrosourea as a carcinogen either alone or in combination with the tumor promoter 12-o-tetradecanoylphorbol-13-acetate (tpa). the frequency of transformation in the absence of tpa was 5 x 10(-4) at 10 micrograms/ml ethylnitrosourea. growth of ethylnitrosourea-treated cells in tpa-substituted medium increased the transformation frequency 8-fold. colonies of transformed cells were isolated from soft agar and analyzed for the pr ... | 1984 | 6704428 |
| mmc-e cells--origin and changes in karyotype accompanying malignant transformation. | karyotype analysis of an established nontumorigenic cell line (mmc-e) indicated that the cells are of rat origin instead of mouse, as interpreted earlier. this cell line, now termed re (rat epithelial) had a karyotype of 39,x,-5,-15,-?16,+t(3q11q) in the stem line. there was also one subline that had a karyotype of 40,x,-5,-15,-?16,+t(3q11q), +?t(5;?). chromosome changes and frequency of sister chromatid exchanges (sces) were studied from seven malignantly transformed re cell lines. these includ ... | 1985 | 3971317 |
| transformation of human bronchial epithelial cells transfected by harvey ras oncogene. | transfection of normal human bronchial epithelial (nhbe) cells with a plasmid carrying the ras oncogene of harvey murine sarcoma virus (v-ha ras) changed the growth requirements, terminal differentiation, and tumorigenicity of the recipient cells. one of the cell lines isolated after transfection (tbe-1) was studied extensively and shown to contain v-ha ras dna. total cellular rna from tbe-1 cells hybridized to v-ha ras structural gene fragment probes five to eight times more than rna from paren ... | 1985 | 3975607 |
| expression of c-mos proto-oncogene transcripts in mouse tissues. | valuable information about proto-oncogenes and their physiological function has been obtained by studying their expression in normal cells. however, expression of the c-mos gene, the cellular homologue of the transforming gene of moloney murine sarcoma virus, has not been detected in normal mouse cells or tissues. the conservation of the c-mos open reading frame strongly indicates that the gene must function during some portion of the animal life cycle, and other lines of evidence suggested to u ... | 1985 | 4000280 |
| expression of glucagon sensitivity by transformed mdck cells normally unresponsive to glucagon: early commitment to differentiation. | a cloned line of canine kidney cells (mdck) transformed with harvey murine sarcoma virus, in contrast to the parental, untransformed line, expressed glucagon sensitivity only under controlled culture conditions. the glucagon sensitivity of transformed mdck cells appeared after 10 days of culture if plated at less than 100,000 cells/dish or after 3 days if cells were plated at greater than 300,000 cells/dish. as there was no effect of conditioned medium from glucagon-sensitive cells on insensitiv ... | 1985 | 4055913 |
| depressed interferon synthesis in skin fibroblasts from lung cancer patients. | skin fibroblast cell cultures, derived from male adult lung cancer patients, an adult control population, and a newborn population were examined for their susceptibility to transformation with kirsten murine sarcoma virus and their ability to respond to an interferon inducer (poly i x poly c). an association between sensitivity to viral transformation and induction of interferon was observed. cultures derived from lung cancer patients demonstrated an increased sensitivity to virus transformation ... | 1985 | 4056491 |
| sarcoma viruses carrying ras oncogenes induce differentiation-associated properties in a neuronal cell line. | the growth-promoting and/or differentiation-blocking activities of kirsten (ki-msv) or harvey murine sarcoma virus (ha-msv) on various types of cells in vitro are well documented. here we report an unexpected effect of these viruses on a rat phaeochromocytoma cell line, pc12. pc12 cells, which multiply indefinitely in growth medium, are known to respond to nerve growth factor (ngf) by cessation of cell division and expression of several properties resembling those of differentiated sympathetic n ... | 1985 | 4058592 |
| characteristics of 30-, 63-, and 89-kilodalton proteins whose secretion from mouse fibroblasts is altered by beta-interferon. | quiescent mouse balb/c-3t3 cells were treated with beta-interferon to induce the secretion of proteins of 30 and 89 kda and with a platelet-derived growth factor preparation to induce the secretion of a 63-kda protein. to label the secreted proteins the cultures were supplemented with [35s]methionine after addition of the inducer. the proteins in the culture fluid were fractionated resulting in a radioactively pure 63-kda protein and 30- and 89-kda protein preparations with residual minor radioa ... | 1985 | 4066715 |
| pathogenicity of retroviruses containing either the normal human c-ha-ras1 gene or its mutated form derived from the bladder carcinoma ej/t24 cell line. | cellular ras oncogenes transduced by retroviruses carry mutations in amino acids 12, 59 and 122. similar mutations have been observed in ras oncogenes activated during induction of neoplasia in both humans and experimental animals. the unmutated normal rat or human c-ha-ras-1 genes have the ability to transform nih 3t3 cells in culture when activated by a rna synthesis promoter. these findings raise the question of whether the mutations are necessary for the ras oncogenes to induce the neoplasti ... | 1985 | 3842394 |
| efficient transcription of a protein-coding gene from the rna polymerase i promoter in transfected cells. | the activity of the mouse ribosomal promoter was examined after fusion to the gene coding for chloramphenicol acetyltransferase (cat) and transfection into mouse cells. very little cat enzyme but high levels of cat-specific rna correctly initiated at the ribosomal dna start site were synthesized. the amount of specific transcripts was neither influenced by long stretches of upstream spacer sequences nor by the insertion of the moloney murine sarcoma virus enhancer. the deletion mutant pmr delta- ... | 1985 | 3856225 |
| infectivity of friend murine leukemia virus for hamster cells. | hamster-adapted friend murine leukemia virus (f-mulv) infected hamster cells and produced an xc-positive progeny. however, the sensitivity of hamster-adapted f-mulv's to hamster cells was about 100 times lower than that to mouse cells. hamster cells chronically infected with f-mulv in vitro produced progeny virus in titers comparable to those in similarly infected mouse cells. xenotropic and amphotropic murine leukemia virus can infect hamster cells when phenotypically mixed with the f-mulv. mur ... | 1985 | 3857383 |
| plasmid-induced "hit-and-run" tumorigenesis in chinese hamster embryo fibroblast (chef) cells. | the chinese hamster embryo fibroblast cell line chef/18 is readily transfected by plasmid dna. in the present transfection studies with chef/18 cells, focus formation induced by plasmids containing the mutant human c-ha-ras gene ej was compared with that of control plasmids without the ej insert. the focus-forming activity of the transfected plasmid j132, a recombinant of the harvey murine sarcoma virus ltr and the normal human c-ha-ras1 in pbr322, also was assessed. foci were recovered after tr ... | 1985 | 3857618 |
| t-cell regulation of erythropoiesis during acute lymphoblastic leukemia. | how and where erythropoiesis is maintained during advanced leukemic disease is an important and, as yet, unresolved question in hematology. to address the potential role of t-lymphocytes as cells that regulate cfu-e differentiation during leukemogenesis, an experimental model of disease has been developed in inbred balb/c mice. specifically, three-week-old balb/c by mice were injected with murine sarcoma virus-murine leukemia virus-moloney (msv-mulv-m), which resulted 6-8 months later in the dev ... | 1985 | 3871705 |
| transformation of mononuclear phagocytes in vivo and malignant histiocytosis caused by a novel murine spleen focus-forming virus. | the study of retrovirus-induced leukaemias in mice is a powerful tool for the elucidation of the normal regulation of the haematopoietic system. the acute murine spleen focus-forming viruses (sffv) can be classified according to the haematopoietic lineage on which they exert their effects in the adult mouse. here we report a new sffv isolate, the af-1 virus, with the novel ability to transform cells of the mononuclear phagocyte lineage. the virus was isolated from sarcomas that were induced on p ... | 1985 | 3873013 |
| characterization of gp85gag as an antigen recognized by moloney leukemia virus-specific cytolytic t cell clones that function in vivo. | the gag membrane protein gp85gag, encoded by moloney murine leukemia virus (m-mlv), was identified as a target molecule recognized by moloney murine sarcoma virus--m-mlv (m-msv--m-mlv)-specific cytolytic t lymphocyte (ctl) clones. target cells infected with ab-x-mlv, an m-mlv-derived mutant virus not encoding gp85gag, were not lysed by the ctl clones. the same ctl clones were shown previously to induce the destruction of m-mlv-induced tumor cells in the peritoneal cavity. we have now characteriz ... | 1985 | 3891902 |
| product of the cellular oncogene, c-fos, observed in mouse and human tissues using an antibody to a synthetic peptide. | the transforming gene of the osteosarcoma-producing fbj murine sarcoma virus, v-fos, is homologous to a normal cellular gene, c-fos, in vertebrate species. transcripts from the c-fos proto-oncogene accumulate to very high levels in late gestational mouse and human extra-embryonic tissues. we now report that these rna transcripts are translated in these tissues. rabbits were immunized with a synthetic peptide whose sequence is common to both c-fos and v-fos. after affinity purification on an immu ... | 1985 | 3894012 |
| p21ras. heterogeneous localization in transformed cells. | the cellular targets for the kirsten murine sarcoma virus (kimsv)-transforming protein, p21ras, are unknown. other studies have indicated that the mature form of p21 is distributed diffusely on the cytoplasmic face of the plasma membrane. however, after fixation without buffer washes, indirect immunofluorescent staining of sparse cultures revealed a particularly well preserved cellular architecture and a strikingly heterogeneous subcellular distribution of p21 in transformed normal rat kidney (n ... | 1985 | 3896830 |
| expression of intact ki-ras p21 protein in escherichia coli. | we have constructed recombinant plasmids capable of expressing in escherichia coli the intact ras p21 protein encoded by kirsten murine sarcoma virus. the ki-ras gene was inserted into an expression vector carrying the e. coli tryptophan promoter and e. coli lipoprotein transcriptional terminator. the resulting plasmids direct the synthesis of large quantities of p21 protein, which represented 20% of the total cellular protein. the ki-ras p21 protein is immunoprecipitated with monoclonal antibod ... | 1985 | 3904744 |
| the mitogenic/oncogenic p21 ki-ras protein stimulates adenylate cyclase activity early in the g1 phase of nrk rat kidney cells. | tsk-nrk rat cells infected with a temperature-sensitive mutant of the kirsten murine sarcoma virus were arrested in the g0/g1 phase of their cell cycle by incubation in serum-deficient medium at a temperature (41 degrees c) which inactivates the virus' abnormally thermolabile mitogenic/oncogenic 21 kda (p 21) ras protein product. reactivating the viral ras protein by lowering the temperature to a permissive 36 degrees c rapidly (within 1 hour) stimulated adenylate cyclase, sensitized the enzyme ... | 1985 | 3904756 |
| characterization and developmental expression of a drosophila ras oncogene. | we cloned a drosophila melanogaster ras gene (dmras64b) on the basis of its homology to the ras oncogen from harvey murine sarcoma virus. this gene mapped at chromosomal position 64b on the left arm of the third chromosome. sequencing of dmras64b revealed extensive amino acid homology with the proteins encoded by the human and saccharomyces cerevisiae ras genes. the coding region of the drosophila gene is interrupted by two introns located in different positions with respect to its human counter ... | 1985 | 3921827 |
| the ras oncogene product p21 is not a regulatory component of adenylate cyclase. | harvey (ha-msv) and kirsten (ki-msv) murine sarcoma viruses induce tumours in animals and transform various cells in culture because of the expression of the ras oncogene product, p21 (ref. 1). proto-oncogenes homologous with these genes are highly conserved evolutionarily and activated ras oncogenes have been detected in many human cancers. whether c-ras oncogenes are directly responsible for human carcinogenesis is uncertain; however, it is clear that p21 mediates virus-induced transformation, ... | 1985 | 3929144 |
| anti-tumour effect of humoral and cellular immunities mediated by a bacterial immunopotentiator, lactobacillus casei, in mice. | administration of a mixture containing lactobacillus casei yit 9018 (lc9018) and methylcholanthrene-induced fibrosarcoma (meth a) cells into the peritoneum of syngeneic balb/c mice suppressed the tumour growth and protected the mice from tumour death. with the appearance of the anti-tumour activity, serum complement-dependent tumour cytotoxic (cdc) antibody was induced on the 5th day after the administration as a result of the adjuvant effect. the cytotoxic antibody was not found in serum on the ... | 1985 | 3930065 |
| biochemical properties of a highly purified v-rash p21 protein overproduced in escherichia coli and inhibition of its activities by a monoclonal antibody. | the v-rash oncogene of harvey murine sarcoma virus encodes a 21,000-dalton p21 protein which has been expressed at a high level as a fusion protein in escherichia coli. we have purified the p21 to over 90% in purity without the use of any detergent or protein denaturant. the purified p21 possesses full biochemical activities of gtp/gdp binding, autokinase, and gtpase. scatchard analysis indicates a single class of binding sites with kd values of 0.83 x 10(-8)m for gtp and 1.0 x 10(-8)m for gdp. ... | 1985 | 3162096 |
| differential transformation of c3h10t1/2 cells by v-mos: sequential expression of transformation parameters. | extremely small quantities of the product of the transforming gene v-mos of moloney murine sarcoma virus are able to efficiently transform cells. recent data indicate the existence of a threshold level for v-mos transformation of nih3t3 cells. using mouse mammary tumor virus long terminal repeat sequences or hybrid promoters consisting of mouse mammary tumor virus and moloney murine sarcoma virus long terminal repeat elements to express v-mos in c3h10t1/2 cells, we established cell lines represe ... | 1985 | 3016522 |
| in vitro cleavage of pr65gag by the moloney murine leukaemia virus proteolytic activity yields p30 whose nh2-terminal sequence is identical to virion p30. | in vitro cleavage of gazdar murine sarcoma virus pr65gag, which has all of the antigenic determinants of moloney murine leukaemia virus pr65gag, i.e. p15, p12, p30 and p10, by the moloney murine leukaemia virus proteolytic activity yielded a p30 whose partial nh2-terminal sequence was identical to moloney murine leukaemia virus. both [3h]leucine-labelled and unlabelled pr65gag were used to generate the cleaved p30. | 1985 | 2578553 |
| amphotropic retrovirus vector transfer of the v-ras oncogene to human hematopoietic and stromal cells in continuous bone marrow cultures. | human continuous bone marrow cultures were established from intraoperative marrow specimens and infected with amphotropic murine leukemia virus (am-mulv) pseudotypes of kirsten or harvey murine sarcoma virus, and the biologic effects were compared with mouse continuous bone marrow cultures. cultures were tested for production of total nonadherent granulocytes and granulocyte-macrophage progenitor cells (gm-cfuc); virus replication by supernatant reverse transcriptase activity; percentage of adhe ... | 1985 | 2578839 |
| neoplastic transformation of human epidermal keratinocytes by ad12-sv40 and kirsten sarcoma viruses. | recent investigations have begun to dissect the number and nature of genetic alterations associated with cancer cells. in the present study, primary human epidermal keratinocytes acquired indefinite life-span in culture but did not undergo malignant conversion in response to infection with a hybrid of adenovirus 12 and simian virus 40. addition of kirsten murine sarcoma virus, which contains a k-ras oncogene, to these cells induced morphological alterations associated with the acquisition of neo ... | 1985 | 2579430 |
| polykaryocytosis induced by amphotropic murine c-type virus (ap129) in sac-cells nonproductively transformed by moloney murine sarcoma virus (mo-msv). | nonproducer cells of stu mouse origin (sac) transformed with moloney murine sarcoma virus (mo-msv) and superinfected with the amphotropic murine c-type virus strain ap 129 unexpectedly formed polykaryocytes. the multinuclear giant cells appeared about 30 days after ap 129 infection as confirmed in three independently performed experiments. the majority of the sac-cells became involved in syncytium formation. the polykaryocytes disappeared during continued culture transfers. various cell lines ob ... | 1985 | 2859766 |
| production of oncogene-specific proteins and human t-cell leukemia (lymphotropic) retrovirus (htlv-i) envelope protein in bacteria and its potential for use in human cancers and seroepidemiological surveys. | the oncogenes coding for the harvey murine sarcoma virus p21ras protein as well as those coding for myc, myb, and mht products were fused to the amino-terminal portion of the bacteriophage lambda cii gene on the expression vector pjl6. in addition two regions of the gene for the human t-cell leukemia virus subgroup i (htlv-i) envelope were expressed in our bacterial system. each of 11 human sera tested that had been shown to contain antibodies to htlv-i or -ii by an enzyme-linked immunosorbent a ... | 1985 | 2861893 |
| coordinate regulation of the levels of type iii and type i collagen mrna in most but not all mouse fibroblasts. | a mouse genomic clone was isolated by cross-hybridization with a dna fragment which codes for the nh2-propeptide of chick alpha1(iii) collagen. the region of cross-hybridization within the mouse clone was localized, its sequence determined, and an exon coding for the nh2-propeptide of mouse alpha1(iii) collagen was identified. this dna fragment hybridizes to an rna species of approximately 5300 nucleotides, slightly larger than the major alpha2(i) collagen rna species. the mouse type iii collage ... | 1985 | 2981217 |
| analysis of viral and somatic activations of the cha-ras gene. | the activation of the cha-ras oncogene in the ej/t24 bladder carcinoma cell line was compared with the activation of the same gene in the rat-derived harvey murine sarcoma virus. the results indicate that, like the human oncogene, the harvey murine sarcoma virus-borne ras gene owes its oncogenic capacity to point mutations in coding sequences rather than to the alteration in transcriptional control that occurred when the formerly cellular ras sequences were acquired by the virus. the viral gene ... | 1985 | 2981345 |
| evidence for multiple steps in neoplastic transformation of normal and preneoplastic syrian hamster embryo cells following transfection with harvey murine sarcoma virus oncogene (v-ha-ras). | neoplastic development of syrian hamster embryo (she) cells in culture is a multistep process in which intermediate or preneoplastic cells can be identified and isolated. in an attempt to further characterize normal and preneoplastic cells, we have compared their susceptibilities to neoplastic transformation following transfection with cloned dna of the oncogenic virus, harvey murine sarcoma virus (hamsv). normal she cells, which are stably nontumorigenic when injected in nude mice, are competen ... | 1985 | 2981612 |
| further characterization of the in vitro products generated by proteolytic cleavage of gazdar murine sarcoma virus p65gag. | in vitro proteolytic cleavage of the gazdar murine sarcoma virus (gz-musv) p65gag polypeptide (gz-p65gag) was facilitated by detergent-disrupted moloney murine leukaemia virus (mo-mulv). incubation of radioactively labelled gz-p65gag in the presence of unlabelled mo-mulv under optimal conditions resulted in the cleavage of gz-p65gag to proteins of 40000 (p40) and 25000 (p25) mr. p40 and p25 appeared to be similar in both mobility and antigenicity to mo-mulv intermediates, pr40gag and pr25gag, pr ... | 1985 | 2981963 |
| temperature-sensitive viral rna expression in moloney murine sarcoma virus ts110-infected cells. | we examined the mos-specific intracellular rna species in 6m2 cells, an nrk cell line nonproductively infected with the ts110 mutant of moloney murine sarcoma virus. these cells present a normal phenotype at 39 degrees c and a transformed phenotype at 28 or 33 degrees c, expressing two viral proteins, termed p85gag-mos and p58gag, at 28 to 33 degrees c, whereas only p58gag is expressed at 39 degrees c. it has been previously shown that 6m2 cells contain two virus-specific rna species, a 4.0-kilo ... | 1985 | 2982039 |
| murine sarcoma virus ts110 rna transcripts: origin from a single proviral dna and sequence of the gag-mos junctions in both the precursor and spliced viral rnas. | our previous studies have argued persuasively that in murine sarcoma virus ts110 (musvts110) the gag and mos genes are fused out of frame due to a approximately 1.5-kilobase (kb) deletion of wild-type murine sarcoma virus 349 (musv-349) viral information. as a consequence of this deletion, infected cells grown at 39 degrees c appear morphologically normal, producing a 4-kb viral rna and a truncated gag gene product, p58gag. at 33 degrees c, however, musvts110-infected cells appear transformed, p ... | 1985 | 2982040 |
| nucleotide sequence analysis of the balb/c murine sarcoma virus transforming gene. | we determined the nucleotide sequence of the v-h-ras-related oncogene of balb/c murine sarcoma virus. this oncogene contains an open reading frame of 189 amino acids that initiates and terminates entirely within the mouse cell-derived ras sequence. the protein encoded by this open reading frame matches the sequence predicted for the t24 human bladder carcinoma oncogene product, p21, in all but two positions. the presence of a lysine residue in position 12 of balb/c murine sarcoma virus p21 likel ... | 1985 | 2983103 |
| thyroid hormone modulation of transformation induced by kirsten murine sarcoma virus. | we have investigated the effect of triiodothyronine (t3) on the transformation of normal rat kidney (nrk) cells by the kirsten strain of murine sarcoma virus (ki-msv). when nrk cells were grown and infected with ki-msv in medium lacking t3, the yield of transformed foci was about one-half that observed in the cultures supplemented with t3. individual foci appeared somewhat later in cells grown out in medium devoid of t3. the yield of ki-msv released from transformed nrk cells was lower when thes ... | 1985 | 2983886 |
| viral harvey ras p21 expressed in escherichia coli purifies as a binary one-to-one complex with gdp. | the ras oncogene of harvey murine sarcoma virus encodes a 21,000-dalton protein, p21, which mediates transformation. viral harvey ras p21, cloned into escherichia coli hb101 lambda/pras1, has been purified to homogeneity by a three-step procedure. the purified e. coli p21 can be bound by a monoclonal antibody to viral harvey ras p21 and has an amino acid composition consistent with that predicted from its dna sequence. purified e. coli p21 has been shown by hplc analysis on an ion-exchange colum ... | 1985 | 2984188 |
| epidermal growth factor precursor is related to the translation product of the moloney sarcoma virus oncogene mos. | murine epidermal growth factor (egf) is synthesized as part of a large precursor (pro-egf), which is thought to span the cell membrane. comparison of the published pro-egf sequence with the sequences of the translation products of viral oncogenes reveals that pro-egf is related to the translation product of mos, the oncogene of moloney murine sarcoma virus. similarity is greatest between the cooh-terminal region of v-mos (residues 317-360) and part of the cytoplasmic domain of pro-egf (residues ... | 1985 | 2984673 |
| development and analysis of a transformation-defective mutant of harvey murine sarcoma tk virus and its gene product. | the harvey murine sarcoma virus has been cloned and induces focus formation on nih 3t3 cells. recombinants of this virus have been constructed which include the thymidine kinase gene of herpes simplex virus type 1 in a downstream linkage with the p21 ras gene of harvey murine sarcoma virus. harvey murine sarcoma tk virus rescued from cells transfected with this construct is both thymidine kinase positive and focus inducing in in vitro transmission studies. the hypoxanthine-aminopterin-thymidine ... | 1985 | 2985821 |
| demonstration of t antigens on the surface of cells transformed with primate polyoma viruses. | primate polyoma virus-transformed hamster, mouse, and rat cell lines were examined by indirect immunofluorescence staining for cell surface-associated t antigens, by using a rabbit antiserum prepared against sodium dodecyl sulfate-denatured large t antigen of simian virus 40 (anti-sv40-sds-t serum). positive surface staining was shown not only on sv40-transformed cells, but also on bk and jc virus-transformed cells. in contrast, normal cells and cells transformed with mouse polyoma-, human adeno ... | 1985 | 2985939 |
| two oncogenes in avian carcinoma virus mh2: myc and mht. | 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, mht and myc are cell-derived mh2-specific sequences, and c is the 3'-terminal retroviral vector sequence. the following results were obtained from the complete nucleotide sequences of the mht and myc genes in mh2. (i) delta gag-mht forms a hybrid gene with a contiguous reading fram ... | 1985 | 2986522 |
| recognition of mos-related proteins with an antiserum to a peptide of the v-mos gene product. | a mos-specific antiserum was generated by injection of rabbits with a peptide predicted from the sequence of the v-mos gene of moloney murine sarcoma virus (musv) strain 124. the peptide is composed of amino acids 37-55 (cyclized at the cysteine residues) conjugated to keyhole limpet haemocyanin. this serum [anti-mos(37-55c)] specifically recognized p37mos in musv-124 acutely infected nih-3t3 cells, p85gag-mos in 6m2 cells, an nrk clone infected with the temperature-sensitive mutant (ts110) of m ... | 1985 | 2987403 |
| friend murine leukemia virus-immortalized myeloid cells are converted into tumorigenic cell lines by abelson leukemia virus. | friend murine leukemia virus (fr-mulv) is a replication-competent murine retrovirus that induces acute nonlymphocytic leukemias in nfs/n mice. fr-mulv disease is divided into two stages based on the ability of the leukemia cells to grow in culture and transplant into syngeneic mice. hematopoietic cells taken from the early stage of disease after fr-mulv infection grow as immortal myeloid cell lines in the presence of wehi-3 cell-conditioned medium (cm) or interleukin 3. these growth factor-depen ... | 1985 | 2987918 |
| rates of evolution of the retroviral oncogene of moloney murine sarcoma virus and of its cellular homologues. | a method is proposed for computing the rates of nucleotide substitution for an oncogene of a retrovirus (v-onc), its cellular homologue (c-onc), and the retrovirus genome simultaneously. the method has been applied to dna sequences of the v-mos gene of moloney murine sarcoma virus (mo-musv) and the c-mos and gag genes of mo-musv and moloney murine leukemia virus (mo-mulv). the rates of nucleotide substitution for c-mos, the gag gene, and v-mos are estimated to be 1.71 x 10(-9), 6.3 x 10(-4), and ... | 1985 | 2987967 |
| mutational analyses of the moloney murine sarcoma virus enhancer. | retroviral enhancers seem to play an integral role in determining tissue tropism. in an attempt to define the sequences essential for moloney murine sarcoma virus (mo-msv) enhancer activity, we have undertaken deletion and insertion mutational analyses of the 72-bp repeats. we demonstrate that, in contrast to simian virus 40 (sv40), the proximal 19 bp of the 72-bp unit of mo-msv are not essential for enhancer function in mouse fibroblasts. our analysis further localizes the 5' boundary of the mo ... | 1985 | 2988891 |
| nucleotide sequence and biochemical activities of the moloney murine sarcoma virus strain ht-1 mos gene. | the nucleotide sequence of the moloney murine sarcoma virus strain ht-1 (ht1msv) mos gene differs from that of the cellular mos gene in three positions, but these are silent changes, and the amino acid sequence of the v-mos and c-mos open reading frames are identical. we have overproduced the mos ht1msv (equivalent to c-mos) in escherichia coli under the control of phage lambda promoter (pl). the e. coli p40mos protein thus obtained was partially purified and examined for several biochemical act ... | 1985 | 2993645 |
| a mos oncogene-containing retrovirus, myeloproliferative sarcoma virus, transforms rat thyroid epithelial cells and irreversibly blocks their differentiation pattern. | differentiated, cloned rat thyroid epithelial cells (424 cells) were infected with a wild-type and a temperature-sensitive strain of the myeloproliferative variant of the moloney murine sarcoma virus. the thyroid cells were productively infected and transformed by both virus strains and displayed some of the typical properties of malignant cells, such as morphological changes, growth in soft agar, and in vivo tumorigenicity. the acquisition of the transformed phenotype by the virus-infected cell ... | 1985 | 2993656 |
| detection of a raf-related and two other transforming dna sequences in human tumors maintained in nude mice. | high molecular weight dnas prepared from a variety of human tumors maintained in nude mice were assayed for their ability to transform nih 3t3 cells. dnas from 4 of 21 tumors tested induced transformed foci in cultures of nih 3t3 cells. they were from a ewing sarcoma line, a glioblastoma line, a leiomyosarcoma line, and a lung carcinoma line. hybridization analyses of the nih 3t3 transformant dnas with a human repetitive sequence as probe revealed that four distinct transforming dna sequences we ... | 1985 | 2994056 |
| contribution of promoter to tissue-specific expression of the mouse immunoglobulin kappa gene. | the immunoglobulin kappa (kappa) gene promoter was activated by a "neutral" enhancer derived from harvey murine sarcoma virus (hamusv) in immunoglobulin-producing myeloma cells, regardless of the enhancer's orientation or position in the vector. in one fibroblast line (3t3) the immunoglobulin kappa gene promoter was completely inactive when linked to the hamusv enhancer, whereas in mouse l cells, promoter activity was observed only with the hamusv enhancer in tandem with the immunoglobulin kappa ... | 1985 | 2994213 |
| detection of the myristylated gag-raf transforming protein with raf-specific antipeptide sera. | the post-translational modifications of the gag-raf fusion proteins of the 3611 murine sarcoma virus (msv) have been examined by inhibiting glycosylation with tunicamycin and by in vivo labeling with [3h]myristic acid. the results show that p75gag-raf is myristylated but not glycosylated and that p90gag-raf is glycosylated but not myristylated (and is now termed gp90gag-raf). gp90gag-raf expression appeared to become lost during passage of the transformed cells, and consequently does not appear ... | 1985 | 2994296 |
| loss of epidermal growth factor receptors and release of transforming growth factors do not correlate with sarcoma virus-transformation in clonally-related nih/3t3-derived cell lines. | transformation of nih/3t3 cells by kirsten murine sarcoma virus (msv) caused a dramatic reduction in the number of cell-surface receptors for epidermal growth factor (egf). however, the number of egf receptors remained at a very low level in a non-tumourigenic revertant cell line isolated from the virus-transformed cells, indicating that an increase in egf receptors is not a requirement for the phenotypic reversion of kirsten msv-transformed 3t3 cells. serum-free conditioned medium from normal a ... | 1985 | 2994627 |
| synthesis of proviral dna in inbred mouse-derived clones of cells expressing different fv-1 phenotypes. | formation of proviral dnas by b-tropic murine leukaemia viruses (mlvs) was examined in n-type and dually permissive mutant cells derived from two inbred mouse strains, ddd and g, both of which are n-type. in the n-type cells, formation of circular proviral dna was strongly suppressed relative to that of linear dna. mutation resulting in loss of the n-type fv-1 restriction resulted in efficient formation of circular dna by the previously restricted b-tropic mlv. this showed that fv-1 restriction ... | 1985 | 2995562 |
| methionine-sensitive glycolysis in transformed cells. | glycolysis in several tumor cell lines grown in tissue culture was inhibited by methionine. kirsten murine sarcoma virus-transformed rat kidney cells (k-nrk) were inhibited 60-75% by 10 mm methionine, whereas normal rat kidney (nrk-49f) cells showed little or no inhibition. inhibition of glycolysis in k-nrk cells was manifest 2-4 hr after exposure to the amino acid. glycolysis in a chemically transformed cell line of madin-darby canine kidney cells was also sensitive to methionine, but maximal i ... | 1985 | 2995983 |
| study of the 78a1 isolate of moloney murine sarcoma virus. i. molecular cloning and characterization. | the 78a1 isolate of moloney murine sarcoma virus (78a1 mo-musv) was cloned from a genomic library obtained from virus producer rat cells, in the lambda vector l47. among the recombinants hybridizing with a probe specific for the v-mos sequences, we recovered a recombinant which contained leukaemia virus (mulv) sequences and was able to transform both mouse and rat cells in transfection experiments. the cloned provirus could be rescued by both mo-mulv ecotropic and amphotropic viruses in mouse ce ... | 1985 | 2997374 |
| study of the 78a1 isolate of moloney murine sarcoma virus. ii. haematopoietic tropism and tumourigenicity. | a new isolate of moloney murine sarcoma virus (mo-musv), designated 78a1, has been molecularly cloned. the cloned genome, found to be larger than that of other known isolates of the same virus is close in size to that of the myeloproliferative sarcoma virus (mpsv), also a derivative of the original mo-musv/moloney murine leukaemia virus (mo-mulv) complex. until now, mpsv was the only mo-musv isolate known to be capable of inducing a myeloproliferative disease associated with a tumoural syndrome ... | 1985 | 2997375 |
| posttranslational processing of p21 ras proteins involves palmitylation of the c-terminal tetrapeptide containing cysteine-186. | the p21 proteins of ras oncogenes are synthesized as precursors in the cytosol. after processing, which involves acylation, the products are associated with the plasma membrane in eucaryotic cells. the p21 overproduced in escherichia coli, however, is not processed by acylation. a synthetic tetrapeptide of the p21 c terminus is used to identify the acylation site in eucaryotic p21 as cysteine-186. the same peptide of bacterial p21 is not acylated. although p21 of harvey murine sarcoma virus-tran ... | 1985 | 2997480 |
| autoregulation plus upstream positive and negative control regions associated with transcriptional activation of the mouse p1(450) gene. | 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd) is known to interact with a cytosolic receptor and, in turn, activate transcription of the mouse p1(450) gene. various lengths of dna upstream of the p1(450) gene were inserted into the psv0-cat expression vector, with and without addition of the harvey murine sarcoma virus (ha-msv) 72-bp repeat enhancer element. the constructs were cotransfected with psv2-neo into mouse hepatoma wild-type cells and two variant cell lines. one variant is believed to res ... | 1985 | 2997746 |
| serine kinase activity associated with maloney murine sarcoma virus-124-encoded p37mos. | an antiserum directed against amino acid residues 37-55 [anti-mos (37-55) serum] of the predicted v-mos sequence was used to precipitate p37mos from moloney murine sarcoma virus-124 (mo-musv-124) acutely infected 3t3 cells. proteins with sizes ranging from p37mos to 43 kda (p43) were found to be phosphorylated when anti-mos (37-55) immune complexes containing p37mos were incubated with [gamma-32p]atp and mn2+. the phosphorylation of p37mos and p43 could be specifically blocked when the anti-mos ... | 1985 | 2998008 |
| presence of circulating antibodies against gag-gene mulv proteins in patients with autoimmune connective tissue disorders. | an immunoblotting procedure using viral proteins from purified murine sarcoma virus or msv-(mlv) has been developed to characterize antiviral antibodies in sera from patients with autoimmune connective tissue disorders. fifty-eight sera with anti-sm, anti-rnp, anti-ss-b (la), and other undefined specificities were found to react with several major viral polypeptide bands. most of them corresponded to gag-gene-encoded products: pr65gag, p40gag, p30, p15, p12 and p10. other bands with molecular we ... | 1985 | 2998055 |
| stage-dependent induction of prenatal tumors in mice by the kirsten and moloney strains of murine sarcoma viruses. | the moloney (momsv) and kirsten (kimsv) strains of murine sarcoma viruses are known to induce mesenchymal sarcomas upon infection of newborn rodents. to determine their activity in mouse embryos, 11- to 15-day-pregnant cd-1 mice were laparotomized, and the single implants were inoculated into the abdominal portion of the embryonal body with an average of 15 and 1500 focus-forming particles/g of body weight of the momsv and kimsv viruses, respectively. another group of less than 1-day-old pups wa ... | 1985 | 2998593 |
| human proto-oncogene c-mos maps to 8q11. | the c-mos proto-oncogene is the cellular counterpart of the viral oncogene v-mos isolated from moloney murine sarcoma virus. the c-mos gene locus has previously been assigned to human chromosome 8. by both in situ hybridization and molecular hydridization to sorted chromosome dna (using a c-mos probe) we have localized the c-mos gene to band 8q11. this regional localization is at variance with the one previously reported at 8q22 and may explain why no rearrangement of c-mos has been found in acu ... | 1985 | 3000766 |
| comparative analysis of p21 proteins from various cell types by two-dimensional gel electrophoresis. | the products of the ras gene family are related proteins at a molecular weight of 21 kda, designated p21. in the present study we used two-dimensional gel electrophoresis to compare p21 proteins from five different normal and malignant cell lines. using a known protein (3h-labeled translation initiation factor [eif-4d]) as a standard internal marker for isoelectric point (pi), we show that p21 proteins from various cells differ only slightly in molecular weight (21-24 kda) but express a wide var ... | 1985 | 3001111 |
| analysis of the cellular proto-oncogene mht/raf: relationship to the 5' sequences of v-mht in avian carcinoma virus mh2 and v-raf in murine sarcoma virus 3611. | the avian carcinoma virus mh2 contains a hybrid gene delta gag-mht with a contiguous open reading frame of 2682 base pairs as well as v-myc and avian helper virus-related sequences. delta gag is a partial retroviral core protein gene while v-mht and v-myc are cell-drived sequences. the v-mht sequence can be divided into two regions: the v-raf-related region at its 3' end contains 969 nucleotides which are 94% related as amino acid sequence to the onc-specific v-raf sequence of murine sarcoma vir ... | 1985 | 3002017 |
| enhancer-dependent expression of the rat preproinsulin gene in bovine papillomavirus type 1 vectors. | the effect of position in a bovine papillomavirus type 1 (bpv-1) vector on foreign gene expression was assessed with the rat preproinsulin (ri1) gene. the ri1 gene was inserted at each of the bpv-1/pml2d junctions in either transcriptional orientation in derivatives of the pdbpv-1(142-6) vector which consists of the bamhi linear genome of bpv-1 dna cloned into pml2d. transformed lines of c127 cells were established and assayed for ri1 gene expression. cells containing the ri1 gene at the 3' end ... | 1985 | 3018523 |
| delineation of transcriptional control signals within the moloney murine sarcoma virus long terminal repeat. | we identified three distinct elements within the moloney murine sarcoma virus long terminal repeat that control transcription. the phenotypes of unidirectional deletion mutants of the long terminal repeat were assayed in microinjected frog oocytes and in transfected mouse fibroblasts. steady-state levels of rna bearing the same 5' terminus as the authentic moloney murine sarcoma viral transcripts were measured by primer extension in assays that included a pseudo-wild-type internal reference. mut ... | 1985 | 3018539 |
| alternate utilization of two regulatory domains within the moloney murine sarcoma virus long terminal repeat. | the moloney murine sarcoma virus long terminal repeat (ltr) harbors two distinct positive activators of transcription, namely, a distal signal and an enhancer. in this report we demonstrate that infection by herpes simplex virus (hsv) can markedly affect the utilization of these two moloney murine sarcoma virus transcription signals. we investigated the hsv-mediated trans-acting effects with two goals in mind: first, to gain insight into ltr function, and second, to probe the mechanisms used by ... | 1985 | 3018540 |
| lysine residue 121 in the proposed atp-binding site of the v-mos protein is required for transformation. | the transforming gene product encoded by moloney murine sarcoma virus clone 124, p37mos, contains a lysine residue (lysine-121) that is conserved among all members of the protein kinase family. this lysine has been shown to be part of a conserved atp-binding site in both the catalytic subunit of the camp-dependent protein kinase and p60v-src. we wished to determine whether this lysine is required for the transforming activity of p37mos. two site-specific mutations were therefore constructed, whi ... | 1985 | 2999782 |
| a camp-independent serine/threonine kinase activity is associated with the mos sequences of ts110 moloney murine sarcoma virus-encoded p85gag-mos. | two proteins, termed p85gag-mos and p58gag, are encoded by the temperature-sensitive transformation mutant, ts110 moloney murine sarcoma virus (musv). based on temperature-shift studies, p85gag-mos is believed to be important for the transforming potential of ts110 musv and has been found to be associated with a thermolabile kinase activity that phosphorylates both p85gag-mos and p58gag in immune complexes. modifications of the original kinase assay conditions are reported here that have allowed ... | 1985 | 2995551 |
| use of site-specific antipeptide antibodies to perturb the serine kinase catalytic activity of p37mos. | the mos oncogene of moloney murine sarcoma virus encodes a protein of approximately 37,000 daltons (designated p37mos). we have detected a serine protein kinase activity which is closely associated with p37mos in immune complexes obtained with antibodies [anti-mos(37-55) serum] that were generated with a peptide containing amino acids 37 through 55 of the v-mos protein (s. a. maxwell and r. b. arlinghaus, virology 143:321-333, 1985). immune complexes that were derived with antibodies generated a ... | 1985 | 2991608 |
| inhibition by retinoic acid of murine retrovirus-induced cellular transformation and tumor formation. | the effect of all-trans-retinoic acid (ra) on cellular transformation and on tumorigenicity of retrovirally transformed cells was investigated. ra treatment of nrk and nih/3t3 cells transformed by balb/c murine sarcoma virus (musv), kirsten murine sarcoma virus (k-musv), and simian sarcoma virus resulted in a significant reduction in anchorage-dependent growth of only k-musv-transformed nrk cells. a 62% reduction in cell number was observed at 10(-5) m ra. in contrast, anchorage-independent grow ... | 1985 | 2987593 |
| myeloid cell transformation by ras-containing murine sarcoma viruses. | balb and harvey murine sarcoma viruses contain ras transforming genes capable of altering the proliferation and differentiation of cells within the erythroid and lymphoid lineages (w. d. hankins and e. m. scolnick, cell 26:91-97, 1981; j. h. pierce and s. a. aaronson, j. exp. med. 156:873-887, 1982; e. m. scolnick et al., mol. cell. biol. 1:68-74). the present studies demonstrate hematopoietic targets of ras-containing viruses within the myeloid lineage. diffuse colonies were induced by balb or ... | 1985 | 2985965 |
| altered metabolism and cell surface expression of glycosphingolipids caused by vitamin e in cultured murine (k3t3) reticulum sarcoma cells. | vitamin e caused a generalized reduction in the metabolism and cell surface expression of glycosphingolipids (gsl) in cultured kirsten murine sarcoma virus-transformed nonproducer (k3t3) cells. metabolism of gangliosides was decreased two- to fourfold in cells treated for 72 hr with 1 and 2 micrograms/ml but not with 12 micrograms/ml vitamin e compared to control cultures. this was demonstrated by a quantitative reduction in precursor 3h-galactose label incorporated in ganglioside fraction and f ... | 1986 | 3540508 |
| mutational analysis of a ras catalytic domain. | we used linker insertion-deletion mutagenesis to study the catalytic domain of the harvey murine sarcoma virus v-rash transforming protein, which is closely related to the cellular rash protein. the mutants displayed a wide range of in vitro biological activity, from those that induced focal transformation of nih 3t3 cells with approximately the same efficiency as the wild-type v-rash gene to those that failed to induce any detectable morphologic changes. correlation of transforming activity wit ... | 1986 | 3023943 |
| ectopic hematopoiesis in peritoneal tumor nodules induced by the myeloproliferative sarcoma virus in dba/2 mice. | tumor nodules composed of fibroblasts, large undifferentiated cells, granulocytes, and small lymphocytes develop in the spleens of adult dba/2 mice infected with the myeloproliferative sarcoma virus (mpsv). they spread thereafter in the organism, and at the terminal stage of the disease they are especially numerous on the peritoneal membrane. the present study, performed on those tumor nodules to avoid contamination by exogenous hematopoietic cells, demonstrated that they were sites of granulopo ... | 1986 | 3456070 |
| [fatty acid content in the muscles and liver of mice developing sarcomas induced by 3-methylcholanthrene and moloney murine sarcoma virus]. | a comparative analysis was made for the fatty acid composition of lipids in the malignant muscular tissue, muscle and liver under blastomogenesis induced in mice by the moloney sarcoma virus and 3-methylcholanthrene. the relation of the found changes in the fatty acid composition to the blastomogenesis stages is shown. the development of the tumour node is accompanied by a decrease of the fatty acid amount in the animal tissues and by its increase in the tumour. a spontaneous regression of the m ... | 1986 | 3948758 |
| direct identification of palmitic acid as the lipid attached to p21ras. | p21v-h-ras, the transforming protein of harvey murine sarcoma virus, contains a covalently attached lipid. using thin-layer chromatography, we identified the acyl group as the 16-carbon saturated fatty acid palmitic acid. no myristic acid was detected in fatty acids released from in vivo-labeled p21v-h-ras. the p21v-k-ras protein encoded by kirsten sarcoma virus was also palmitylated. the processing and acylation of p21v-k-ras however differed from that of p21v-h-ras. three forms of [3h]palmitic ... | 1986 | 3023817 |
| the effect of cerulenin on the synthesis of the precursor gag polyprotein in defective murine leukemia and sarcoma virus producing cell lines. | the effect of cerulenin, an inhibitor of de novo fatty acid (and cholesterol) biosynthesis, on the synthesis of the precursor gag polyprotein, pr65gag in a defective murine leukemia virus (334c) producing murine cell line (3je) and a defective murine sarcoma virus (gazdar) producing hamster cell line (htg-2) was examined. in contrast to moloney murine leukemia virus (m-mulv) producing cell lines (mjd-54, clone 2) the amount of the pr65gag remaining in the presence of cerulenin (20 micrograms/ml) ... | 1986 | 3019002 |
| modulation by normal serum factors of kirsten murine sarcoma virus-induced transformation in adult rat cells infected in early passage. | adult rat adrenal cells, infected with kirsten murine sarcoma virus in early passage, transform consistently in 10% fetal bovine serum (fbs)-supplemented medium. substitution of 3% horse serum (hs) for fbs reverses early foci and delays transformation. the influence of the serum on dna synthesis, anchorage dependence, tumorigenicity, and subcellular mr 21,000 transforming protein (p21) distribution was followed from infection in passage 1 to complete transformation. in fbs, increased expression ... | 1986 | 3019533 |
| molecular cloning of the temperature-sensitive 371 kirsten murine sarcoma virus and expression in escherichia coli of the mutant and wild-type viral kirsten ras p21 proteins. | rodent fibroblasts infected with the ts371 kirsten murine sarcoma virus (kimusv) are temperature sensitive for the maintenance of transformation because of the production of an abnormal p21 protein. we cloned the ts371 kimusv provirus from the genome of a conditionally transformed nonproducer cell line, ts371 kimusv nrk clone 5 (t. y. shih, m. o. weeks, h. a. young, and e. m. scolnick, j. virol. 31:546-556, 1979). the molecularly cloned virus had 1,000-fold lower transformed focus-forming activi ... | 1986 | 3022010 |
| suppression of tumor growth by senescence in virally transformed human fibroblasts. | normal human cells whether embryonic, neonatal, or adult are resistant to experimentally induced tumorigenesis in contrast to rodent or chicken cells. we showed previously that neither transformation with simian virus 40 dna nor transfection with human mutant hras dna immortalized fs-2 cells (diploid, neonatal human fibroblasts). further, tumorigenicity was not induced, despite expression of the respective transforming gene products tumor (t) antigen or p21. here we describe treatment of fs-2 an ... | 1986 | 3022300 |
| the effect of viral transformation on prostaglandin production depends on cell type. | the role of prostaglandins in cellular differentiation and transformation has been widely studied. we have found previously that prostaglandin e2 production was greatly diminished in dog kidney cells (mdck) after transformation by harvey murine sarcoma virus. in the present study, we have shown that viral transformation can have differing effects in the ability to modify the production of prostaglandin in cultured cells. for example, the prostaglandin e2 production in rat kidney cells (nrk) is d ... | 1986 | 3022469 |
| altered cellular functions in a pc-12 cell clone chronically infected with retrovirus. | we characterized retrovirus-induced changes in pc-12 cell function and neuronal differentiation. pc-12 cells were infected with a neurotropic retrovirus (temperature-sensitive moloney murine leukemia virus, mutant ba-1). we isolated a cell clone from this infected culture that displayed altered response to nerve growth factor; increased choline acetyltransferase activity; and decreased basal and nerve growth factor-stimulated acetylcholinesterase activity. in addition, kirsten murine sarcoma vir ... | 1986 | 3022728 |
| assignment of ras proto-oncogenes in chinese hamsters: implications for mammalian gene linkage conservation and neoplasia. | hras and kras are the cellular homologs of the oncogenic transforming genes found in the harvey strain of murine sarcoma virus and the kirsten murine sarcoma virus, respectively. phyla as diverse as insects, birds, and mammals possess distinct hras and kras sequences, suggesting that these genes are essential to metazoa. in this report, we used a clone panel of chinese hamster x mouse c11d somatic cell hybrids segregating hamster chromosomes to map those genes. southern filter hybridization anal ... | 1986 | 3022995 |
| expression of viral p21ras during acquisition of a transformed phenotype by rat adrenal cortex cells infected with kirsten murine sarcoma virus. | rat adrenal cortex cells infected with kirsten murine sarcoma virus acquire a transformed phenotype in a progressive fashion. the expression of the viral p21ras does not appear to correlate with the degree of transformation of the adrenocortical cells but rather is produced at similar levels as the culture becomes transformed. this indicates that the expression of an oncogenic form of p21ras is not of itself sufficient to completely transform rat adrenal cortex cells. | 1986 | 3023835 |
| two different factors act separately or together to specify functionally distinct activities at a single transcriptional enhancer. | the expression of genes fused downstream of the moloney murine sarcoma virus (momsv) long terminal repeat is stimulated by glucocorticoids. we mapped the glucocorticoid response element that conferred this hormonal regulation and found that it is a hormone-dependent transcriptional enhancer, designated sg; it resides within dna fragments that also carry a previously described enhancer element (b. levinson, g. khoury, g. vande woude, and p. gruss, nature [london] 295:568-572, 1982), here termed s ... | 1986 | 3023887 |
| interaction of distinct nuclear proteins with sequences controlling the expression of polyomavirus early genes. | the interaction between cellular factors and polyoma virus (py) dna was investigated by using a gel retention assay. nuclear extracts from various cell lines (nih 3t3, nih 3t6, ltk-, f9) contained proteins that formed specific and distinct complexes with py b enhancer fragments of either wild-type or f9-1 mutant origin. the presence of an excess amount of other well-characterized dna sequences, including the py a enhancer, the murine sarcoma virus enhancer, and the simian virus 40 enhancer-promo ... | 1986 | 3023889 |
| nucleotide sequence of the two rat cellular rash genes. | we present the nucleotide sequence of the coding region of the rat c-rash-1 gene and a partial sequence analysis of the rat c-rash-2 gene. by comparing these sequences with the harvey murine sarcoma virus ras gene, we predict that the p21 protein encoded by the harvey virus differs from the cellular c-rash-1-encoded p21 at only two amino acids; those at positions 12 and 59. alterations at each of these positions may play a role in activating the viral p21 protein. the c-rash-2 gene is likely to ... | 1986 | 3023901 |
| temperature-dependent cytocidal effects of moloney murine sarcoma virus. | infection of l6e9 rat myoblasts with moloney murine sarcoma virus (mo-musv) at 37 degrees c resulted in the killing of target cells in less than one week. however, cells infected at 37 degrees c and shifted to 40 degrees c were not killed but underwent morphological transformation and had reduced levels of virus-specific rna. a marked decrease in a cellular 55 kda protein, as judged by immunoblotting, correlated with increased expression of mo-musv rna in infected cells. | 1986 | 3026112 |
| abelson virus drives the differentiation of harvey virus-infected erythroid cells. | abelson murine leukemia virus (a-mulv) and harvey murine sarcoma virus (ha-msv) are retroviruses carrying unrelated onc genes. however, both of these viruses are capable of stimulating the growth and differentiation of erythroid precursor cells; the target cells for both appear at the same time during fetal development and follow a similar pattern throughout ontogeny. in addition, the colonies induced by each virus are morphologically similar and synthesize the adult form of hemoglobin. however, ... | 1986 | 3002634 |
| revertants of ha-musv-transformed mdck cells express reduced levels of p21 and possess a more normal phenotype. | four subclones of the originally cloned harvey murine sarcoma virus-transformed madin darby canine kidney (mdck) cells have been isolated. these subclones fall into two general classes. two subclones have a fibroblastic morphology, have lost the growth requirement for prostaglandin e1 (pge1), do not respond to glucagon or vasopressin, and, in general, appear transformed. two other subclones have epithelioid morphologies, are growth-stimulated by pge1, respond to vasopressin with an increase in i ... | 1986 | 3002821 |
| an endogenous mouse mammary tumor virus genome common in inbred mouse strains is located on chromosome 6. | we have examined ecori-restricted cellular dna from mouse-hamster somatic cell hybrids. results of this analysis show that the unit ii mouse mammary tumor virus proviral genome is located on mouse chromosome 6. restriction analysis of cellular dna from (c3h/ouj x czech ii) x czech ii backcross mice showed a strong linkage between unit ii and igk. the gene order of these markers on chromosome 6 relative to the raf and kirsten murine sarcoma virus ras-2 proto-oncogenes was established. | 1986 | 3003402 |
| monoclonal antibody detection of transformation associated protein (tap) in ts110 moloney murine sarcoma virus transformed 6m2 cells that are different from the mos gene product. | by the use of a highly specific monoclonal antibody (designated mc), we were able to detect three radiolabeled bands with molecular weights of 60,000, 63,000, and 66,000 daltons in the ts-110 moloney murine sarcoma virus mutant-transformed rat kidney cells known as 6m2. expression of transformation properties as well as these three bands in 6m2 cells was found to be temperature sensitive. therefore, mc detected factors that are apparently associated with the transformation of 6m2 cells. these fa ... | 1986 | 3004486 |
| homologous recognition of a promoter domain common to the msv ltr and the hsv tk gene. | we have partially purified, from rat liver, a nuclear protein fraction with sequence-specific affinity to a promoter domain shared by the herpesvirus tk gene and the moloney murine sarcoma virus ltr. for both promoters, the protein-binding domain occurs roughly 80 bp upstream of the mrna cap site and harbors the pentanucleotide sequence 5'-ccaat-3'. the msv ltr pentanucleotide occurs on the coding strand in an orientation pointing toward the retroviral transcription unit. the hsv tk pentanucleot ... | 1986 | 3004739 |
| oncogenic retrovirus from spontaneous murine osteomas. ii. molecular cloning and genomic characterization. | an n-ecotropic murine leukemia virus (oa mulv), originally isolated from spontaneous osteomas of strain 101 mice, was molecularly cloned. the virus induces osteomas, osteopetrosis, and malignant lymphomas in nmri mice. the cloned virus was analyzed by heteroduplex analysis, restriction enzyme mapping, and oligonucleotide mapping. the data show a very close relationship to the endogenous akv prototype virus with some differences in the gag and the env region. the nucleotide sequence of the u3 reg ... | 1986 | 3006346 |
| hydrocortisone promotes the neodifferentiation of kirsten murine sarcoma virus transformed human skin fibroblasts to adipose cells: relevance to oncogenic mechanisms. | here we have demonstrated that transformation of human skin fibroblasts (sf) by the kirsten murine sarcoma virus (kimsv) is associated with their neodifferentiation into preadipose cells. hydrocortisone (hc) promotes the transformation/neodifferentiation of such preadipocytes into mature fat cells. the effects of hc on the expression of adipocyte-containing foci and on the total number of transformed foci present in kimsv-treated cultures appeared to be dose-dependent and was optimal at a concen ... | 1986 | 3007230 |
| an agent or agents produced by virus-transformed cells cause unregulated ruffling in untransformed cells. | knrk cells (a normal rat kidney [nrk] cell line transformed by kirsten murine sarcoma virus) in sparse culture exhibit a highly ruffled morphology, but the cause of this ruffling is unknown. in this study, we have demonstrated that the continuous, excess ruffling on knrk cells is caused by one or more soluble agents secreted by the knrk cells themselves. to do this study, an assay for ruffling responses in live cell cultures was defined, and its reproducibility was demonstrated. this assay permi ... | 1986 | 3007528 |
| cell-mediated co-action of transforming growth factors: incubation of type beta with normal rat kidney cells produces a soluble activity that prolongs the ruffling response to type alpha. | intense, continuous ruffling is a characteristic of many transformed cells, but untransformed cells ruffle intensely only briefly after exposure to growth factors. we reported previously that cells of a normal rat kidney (nrk) cell line transformed by kirsten murine sarcoma virus secrete their own ruffle-inducing agent(s) that cause sustained ruffling in either themselves or untransformed nrk cells. in the present study, we examined the roles of the transforming growth factors tgf-alpha and tgf- ... | 1986 | 3007529 |
| nucleotide sequence of exon i of the rat c-k-ras gene. | we have isolated a dna fragment containing exon i of rat cellular proto-oncogene of k-ras and sequenced the exon i. the obtained sequence was compared with that of the corresponding region in viral oncogene of kirsten strain of murine sarcoma virus (ki-msv). the results showed that the exon i sequences of cellular k-ras genes in rat and human cells could encode the same amino acid sequence, while the viral k-ras gene could code for two different amino acids corresponding to the 12th and 37th pos ... | 1986 | 3009041 |