Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| transforming ability of avian defective leukemia viruses in early embryogenesis. | the response to infection of chicken hemopoietic cells derived from the early stages of embryogenesis by avian myeloblastosis virus (amv) and avian erythroblastosis virus (aev) was investigated. it was found that erythroid progenitor cells were present in the blastoderm at a higher frequency than that of myeloid progenitor cells. these results correlate with the observation that target cells for aev were found to be more numerous than those for amv. therefore, blastoderm cells are of potential v ... | 1983 | 6297153 |
| complete nucleotide sequence of alfalfa mosaic virus rna 1. | double-stranded cdna of alfalfa mosaic virus (almv) rna 1 has been cloned and sequenced. from clones with overlapping inserts, and other sequence data, the complete primary sequence of the 3644 nucleotides of rna 1 was deduced: a long open reading frame for a protein of mr 125,685 is flanked by a 5'-terminal sequence of 100 nucleotides and a 3' noncoding region of 163 nucleotides, including the sequence of 145 nucleotides the three genomic rnas of almv have in common. the two uga-termination cod ... | 1983 | 6298738 |
| complete nucleotide sequence of alfalfa mosaic virus rna 2. | double-stranded cdna of in vitro polyadenylated alfalfa mosaic virus (almv) rna 2 has been cloned and sequenced. the use of an oligodeoxyribonucleotide corresponding to the known sequence of the 5'-end of rna 2 to prime second-strand dna synthesis, enabled us to construct the complete primary structure of almv rna 2. the sequence of 2,593 nucleotides contains a long open reading frame for a protein of mr 89,753 starting at the first aug codon from the 5'-end. this coding region is flanked by a 5 ... | 1983 | 6304618 |
| identification of the leukemogenic protein of avian myeloblastosis virus and of its normal cellular homologue. | the genome of the replication-defective avian myeloblastosis virus (amv) contains an inserted cellular sequence (amv) that is part of the oncogene responsible for acute myeloblastic leukemia in chickens infected with amv. three antisera raised against distinct synthetic peptides predicted from the long open reading frame of amv specifically precipitated the same 48-kilodalton protein (p48amv) from leukemic myeloblasts but not from normal hematopoietic tissue, fibroblasts, or from fibroblasts inf ... | 1983 | 6304685 |
| the product of the retroviral transforming gene v-myb is a truncated version of the protein encoded by the cellular oncogene c-myb. | avian myeloblastosis virus (amv) is an oncogenic retrovirus that rapidly causes myeloblastic leukemia in chickens and transforms myeloid cells in culture. amv carries an oncogene, v-myb, that is derived from a cellular gene, c-myb, found in the genomes of vertebrate species. we constructed a plasmid vector that allows expression of a portion of the coding region for v-myb in a procaryotic host. we then used the myb-encoded protein produced in bacteria to immunize rabbits. the antisera obtained p ... | 1983 | 6305504 |
| tripartite structure of the avian erythroblastosis virus e26 transforming gene. | only two avian oncogenic viruses specifically cause acute leukaemias yet do not transform chicken fibroblasts in culture: e26, which causes erythroblastosis and a low level of concomitant myeloblastosis in chickens, and avian myeloblastosis virus (amv), which causes myeloblastosis exclusively. both viruses are replication-defective and share a sequence termed myb (also known as amv) which is unrelated to essential virion genes and is therefore thought to be part of the transforming onc genes of ... | 1983 | 6316155 |
| 5'-conformation of capped alfalfa mosaic virus ribonucleic acid 4 may reflect its independence of the cap structure or of cap-binding protein for efficient translation. | most eukaryotic mrnas are characterized by the presence of a 5'-terminal cap structure (m7gpppn), and removal of the cap or translation of capped mrnas in the presence of cap analogues (m7g) results in most cases in a significant decrease in the translational efficiency of the mrnas. one way of explaining the importance of the 5'-cap is that cap-binding proteins recognize the cap structure, destabilize the mrna secondary structure, and thus allow the 40s ribosomal subunit to bind to the mrna [so ... | 1983 | 6317016 |
| production and characterization of monoclonal antibodies against avian myeloblastosis virus. | hybridomas were prepared by fusion of mouse myeloma cell line sp2/0 with lymphocytes from mice immunized with avian myeloblastosis virus (amv). the specificity of each monoclonal antibody was characterized by radioimmunoassay (ria) using purified viral core proteins, immunoprecipitation of radioactively labeled virus (35s-methionine-labeled amv, 125j-labeled amv) and immunoblotting. one monoclonal antibody (ic11) which is of igg1 subclass, and two other monoclonal antibodies (if9 and ib8), both ... | 1983 | 6318135 |
| structure of a t = 1 aggregate of alfalfa mosaic virus coat protein seen at 4.5 a resolution. | a t = 1 empty aggregate of alfalfa mosaic virus coat protein had been crystallized in a hexagonal unit cell and its orientation was determined with the rotation function. a single heavy-atom derivative has now been prepared and the position of the two hg atoms per protein subunit were determined using a systematic patterson search procedure, given the particle orientation. phases, initially determined by single isomorphous replacement, were refined by six cycles of electron density averaging and ... | 1983 | 6876169 |
| sites of heavy atom substitution in alfalfa mosaic virus crystals. | 1983 | 6876170 | |
| structure of the 5'-terminal untranslated region of the genomic rnas from two strains of alfalfa mosaic virus. | we report the sequences of the 5'-terminal regions of the 3 alfalfa mosaic virus genomic rnas for the strasbourg strain (almv-s) and for a new isolate, almv-b; they are compared to similar data obtained by koper-zwarthoff et al. (nucleic acids res. 1980, 8, 5635-5647) for strain 425. the structure of these leaders is highly conserved in rnas 1 and 2. the length of the leader is 102, 100 and 101 nucleotides in rna1 for strains s, b and 425 respectively; 55 and 56 in rna2 for strains s and b respe ... | 1983 | 6856476 |
| complete nucleotide sequence of alfalfa mosaic virus rna3. | a full-length cdna clone of alfalfa mosaic virus (amv) rna3 was prepared and sequenced. the 2,037 base sequence contains two open reading frames of 903 and 666 nucleotides that code for a 32,400 dalton protein (32.4k protein) and the 24,380 dalton coat protein, respectively. a 5'-noncoding sequence of 240 bases preceeding the 32.4k protein contains homologous regions that may have a function in its translation. the intercistronic junction is 49 bases long, the last 36 bases representing the 5'-e ... | 1983 | 6856479 |
| inhibition of alfalfa mosaic virus rna and protein synthesis by actinomycin d and cycloheximide. | actinomycin d, added early after inoculation, reduces the production of infectious alfalfa mosaic virus in cowpea protoplasts by 90%. this reduction was associated with an inhibition of viral minus-strand and plus-strand rna synthesis, suggesting the involvement of host factors in these processes. coat protein production was less affected by the drug. addition of cycloheximide throughout the growth cycle resulted in an immediate cessation of coat protein production and an enhanced degradation of ... | 1983 | 6857995 |
| the transforming gene of avian myeloblastosis virus (amv): nucleotide sequence analysis and identification of its translational product. | the genome of the avian myeloblastosis virus (amv) has undergone a sequence substitution in which a portion of the region normally coding for the env protein has been replaced by cellular sequences. we have determined the complete nucleotide sequence of this region. examination of the amv oncogenic sequence revealed an open reading frame starting with the initiation codon atg and terminating with the triplet tag within the acquired cellular sequences and terminating with the triplet tag at a poi ... | 1983 | 6305788 |
| the mechanism of inhibition of avian myeloblastosis virus reverse transcriptase by a dialdehyde derivative of atp. inactivation of essential sulfhydryl group function. | the dialdehyde derivative of atp inhibits dna synthesis by amv reverse transcriptase, while the polymerase-associated ribonuclease h activity is significantly resistant to this reagent. neither atp nor its dialcohol form effectively block dna synthesis, indicating that the aldehyde moiety is required for inhibition. the nature of the reactivity of dialdehyde-atp with amv reverse transcriptase has been examined and we find that: (a) inhibition is non-competitive with respect to substrate deoxynuc ... | 1983 | 6189518 |
| a higher affinity of amv reverse transcriptase for template-primers correlates with a lower rate of dna synthesis. | the kinetics of copying of poly (a)--oligo (dt) and poly (c)--oligo (dg) by reverse transcriptase from avian myeloblastosis virus have been studied, and binding affinity of enzyme for template-primer and primer alone have been determined separately. although the maximal rate of dna synthesis obtained with poly (c)-oligo (dg) is higher than that for poly (a)-oligo (dt), the binding affinity of the enzyme for poly (c)-oligo (dg) or oligo (dg) is considerably lower than that for poly (a)--oligo (dt ... | 1983 | 6193009 |
| organization of chicken dna sequences homologous to the transforming gene of avian myeloblastosis virus. ii. isolation and characterization of lambda proto-amv dna recombinant clones from a library of leukemic chicken dna. | several lambda proto-amv recombinants isolated from a lambda charon 4a library of leukemic chicken dna were analyzed by using various restriction endonucleases and hybridization with specific probes representing different regions of the transforming gene of avian myeloblastosis virus. the position of 30 sites for 11 different restriction endonucleases was established in the proto-amv region of chicken dna. identical restriction endonuclease maps were obtained for the normal and leukemic dnas in ... | 1983 | 6300463 |
| the human dna locus related to the oncogene myb of avian myeloblastosis virus (amv): molecular cloning and structural characterization. | chicken and human cell dna contains sequences homologous to the avian myeloblastosis virus oncogene, v-myb. these cellular sequences, c-myb (human) and c-myb (chicken), were isolated from libraries of human or chicken cell dna fragments, generated by partial digestion with the restriction enzymes alui and haeiii, and compared. the chicken c-myb locus isolated from two distinct overlapping recombinant phages, contained five contiguous ecori fragments of 5.4, 1.1, 2.1, 2.2 and 9 kbp, accounting fo ... | 1983 | 6194989 |
| use of monoclonal antibodies against avian retroviral protein p19 for competitive radioimmunoassay and immunodiffusion. | monoclonal antibodies were used in competitive binding assays to investigate the arrangement of three epitopes on the protein p19 of avian myeloblastosis virus (amv). it was reasoned that if the epitopes recognized by two monoclonal antibodies are physically close, the binding of one antibody will sterically block the binding of the second; conversely no blocking will occur if the epitopes are sufficiently distant. the results of these competitive binding assays demonstrated the presence of two ... | 1983 | 6197663 |
| structural analysis of rna subunits from avian myeloblastosis virus (amv). | subgenomic fragments were released from purified 35s amv rna using strongly denaturing conditions of 78% formamide and 3.9 m urea at 53 degrees c. the fragments were characterized by sedimentation and electron microscopic analysis. the presence of five distinct, reproducible size classes of rna molecules with mean lengths 1.79 +/- 0.07 micron, 1.36 +/- 0.09 micron, 1.03 +/- 0.09 micron, 0.7 +/- 0.08 micron, and 0.42 +/- 0.09 micron were demonstrated. analysis of poly(a)+ and poly(a)- rna fragmen ... | 1983 | 6138994 |
| 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 |
| inhibition of reverse transcriptase activity of avian myeloblastosis virus by pyrophosphate analogues. | several pyrophosphate analogues have been studied for their effects on avian myeloblastosis virus reverse transcriptase and on cellular dna polymerase alpha. examination of structure-activity relationships for these compounds revealed that two acidic groups connected by a short bridge were necessary, but not sufficient, for inhibition of the enzyme activities. foscarnet sodium (trisodium phosphonoformate) was the most potent inhibitor of reverse transcriptase, giving non-competitive inhibition o ... | 1982 | 6179470 |
| inhibition of avian myeloblastosis virus reverse transcriptase and virus inactivation by metal complexes of isonicotinic acid hydrazide. | the cupric and ferric complexes of isonicotinic acid hydrazide (inh) inhibit the dna synthesis catalysed by avian myeloblastosis virus (amv) reverse transcriptase. the inhibition was to the extent of 95% by 50 microm of cupric-inh complex and 55% by 100 microm of ferric-inh complex. these complexes have been found to bind preferentially to the enzyme than to the template-primer. kinetic analysis showed that the cupric-inh complex is a non-competitive inhibitor with respect to dttp. the time cour ... | 1982 | 6185090 |
| differential inhibition of dna polymerase and rnase h activities of the reverse transcriptase by phosphonoformate. | three potential inhibitors of reverse transcriptase activities, phosphonoformate (pf), phosphonoacetate (paa), and ethyl-diethyl phosphonoformate (et-pf), were compared in this study. only pf was found to inhibit the dna polymerase activity of the purified reverse transcriptase of moloney murine leukemia virus (m-mulv) and avian myeloblastosis virus (amv). the degree of dna polymerase inhibition was linear with pf concentration; 50% inhibition was achieved at 10 mum. whereas pf inhibited both th ... | 1982 | 6178013 |
| studies on the structure of avian myeloblastosis virus (amv) rna. i. factors affecting electron microscopic visualization of amv rna. | factors affecting the visualization of single-stranded (ss) avian myeloblastosis virus (amv) rna by the basic protein film technique under strong denaturation conditions were studied. the basic parameters of the electron microscopic picture of ss rna, involving the visibility, concentration and contour lengths of molecules, were found to be significantly dependent on the (1) quality of denaturing components used for full extension of amv rna molecules and (2) spreading and formation of the surfa ... | 1982 | 6124101 |
| studies on the structure of avian myeloblastosis virus (amv) rna. ii. integrity of the rna in dependence on rna isolation and virus propagation. | while sedimentation analysis revealed no basic changes in the sedimentation characteristics of 60-70 s avian myeloblastosis virus (amv) rna isolated under different conditions from two sources, electron microscopy exhibited differences in the length distributions of this rna. based on the length distribution profiles, phenol extraction showed a higher degradation effect in comparison with direct gradient centrifugation of viral lysates. proteinase k appeared to be a more suitable nuclease inhibi ... | 1982 | 6124106 |
| studies on the structure of avian myeloblastosis virus (amv) rna. iii. electron microscopic definition of secondary structure. | the secondary structure of avian myeloblastosis virus (amv) rna was characterized by electron microscopy under moderately denaturing spreading conditions. under denaturation by aqueous 44% formamide or 77% formamide in the presence of salts, partly stretched rna molecules with measurable double-stranded regions were observed. this approach allowed the localization from 5 to 11 regions of preserved secondary structure on amv rna molecules. topographic analysis revealed a nonrandom occurrence of s ... | 1982 | 6124107 |
| electron microscopic studies on the structure of 60-70s rna of avian myeloblastosis virus. | structural properties of the 60-70s rna complex of avian myeloblastosis virus (amv) were analysed in electron microscope after treatment under a set of non-denaturing, gently and strongly denaturing conditions. by selected denaturing conditions, the significant fraction of 60-70s amv rna molecules revealed partially unfolded structures either in a dimer or a more complex form and in a length corresponding to mol. wt. of 5.6 x 10(6). the typical dimers contained a characteristic central structure ... | 1982 | 6132536 |
| reverse transcriptase associated with avian sarcoma-leukosis viruses. i. comparison of intra-virion content of multiple enzyme forms. | the rna-dependent dna polymerase (the reverse transcriptase) was solubilized from three related strains of avian sarcoma virus (asv b77, asv tsla334, and asv qv2) as well as avian myeloblastosis virus (amv) and a chicken endogenous virus (rav-o), by a combination of non-ionic detergent treatment and cscl step-gradient centrifugation, and was subsequently separated into individual enzyme forms by poly(c)-agarose column chromatography. the newly developed two-step method allowed us to purify the t ... | 1982 | 6175623 |
| avian myeloblastosis virus transforming gene is related to unique chicken dna regions separated by at least one intervening sequence. | identification of several additional restriction endonuclease sites within the cellular substitution (amv) inserted into the avian myeloblastosis virus proviral genome has permitted us to isolate different regions of the amv sequence. these subsets of the avian myeloblastosis virus transforming gene have been cloned in the plasmid pbr322 and used as hybridization probes to investigate the topology of homologous (proto-amv) normal chicken dna sequences. the results showed that the cellular proto- ... | 1982 | 6283118 |
| reverse transcriptase associated with avian sarcoma-leukosis viruses. ii. comparison of subunit structure and catalytic properties. | the three enzyme forms (alpha, alpha beta-, and beta-form) of the rna-dependent dna polymerase (the reverse transcriptase) from three strains of avian sarcoma virus (asv b77, asv tsla334, and asv qv2) and one exogenous (avian myeloblastosis virus (amv)) and one endogenous avian leukosis virus (rous-associated virus type-0 (rav-0) were compared with each other in subunit structure and catalytic properties. despite the gross similarity in the subunit molecular weight (mr(alpha) = 65,000 and mr(bet ... | 1982 | 6175624 |
| immune stimulation of sensitized chicken lymphocytes by avian retrovirus proteins. | peripheral blood lymphocytes of chickens bearing tumours induced by avian sarcoma virus can be specifically stimulated to divide by the crude culture fluids of virus-infected cells. in this communication, we show that relevant antigenic activity apparently resides in each of the internal virus proteins p15 and p27. the ability of infectious culture fluids to be mitogenic for sensitized lymphocytes is greatly reduced following treatment with antibodies specific for either total avian myeloblastos ... | 1982 | 6286858 |
| 5-mercaptopolyuridylic acid (mpu), a potent inhibitor of the reverse transcriptase from avian myeloblastosis virus. | the effects of partially thiolated polyuridylic acid (mpu), partially thiolated polycytidylic acid (mpc), and their unmodified counterparts, poly(u) and poly(c), respectively, on the reverse transcriptase of avian myeloblastosis is virus (amv) have been determined, using different template-primers. poly(c) stimulated and mpc inhibited the polymerization reaction catalyzed by the amv reverse transcriptase in the presence of the natural viral template (endogenous rna or purified 70s rna), or with ... | 1982 | 6179137 |
| effect of acetylated and deacetylated 2-aminofluorene adducts on in vitro dna synthesis. | we have constructed primed phi x174 dna templates containing either acetylated or deacetylated aminofluorene adducts at the c-8 position of guanine. t4 dna polymerase terminates synthesis one nucleotide before the acetylated adducts but incorporates an additional nucleotide opposite the deacetylated guanylaminofluorene. these observations can be explained by the known preferred conformations of the acetylated and deacetylated guanosinylaminofluorene nucleosides--the former favoring the syn confo ... | 1982 | 6185946 |
| protein binding sites in nucleation complexes of alfalfa mosaic virus rna 4. | the subgenomic coat protein messenger rna 4 of alfalfa mosaic virus forms complexes with one and three coat protein dimers, which are designated complexes i and iii, respectively. these complexes were separated, subjected to digestion with ribonuclease t1, and filtered onto millipore filters. phenol extracts of the filters contained specific fragments of rna 4, which were sequenced after electrophoretic separation on nondenaturing and denaturing polyacrylamide gels. complex i yielded only a 68-n ... | 1982 | 6810924 |
| disintegration of retroviruses by chelating agents. | exposure in vitro of various mammalian retroviruses to the chelating agents edta or egta in millimolar concentrations resulted in partial disintegration of viral membranes as measured by accessibility or even release of reverse transcriptase, an internal viral protein, without any other treatment usually required. among the viruses responding to chelators were mammalian type c viruses, primate type d viruses and bovine leukemia virus. the effect was dose-dependent. the avian type c virus amv, ho ... | 1982 | 6816193 |
| differential expression of the amv gene in human hematopoietic cells. | total cellular rnas from a variety of fresh and culture-derived human hematopoietic neoplastic cell types at various stages of differentiation and human sarcoma, carcinoma, melanoma, and glioblastoma cell lines were enriched for poly(a)- containing sequences, fractionated by gel electrophoresis, and blot hybridized to a cloned dna probe containing the transforming sequences (v-amv) of avian myeloblastosis virus (amv), a virus known to cause myeloid leukemias in chickens. expression of rna sequen ... | 1982 | 6954533 |
| levels of colony-stimulating and inhibiting activities in chicks with myeloblastic leukemia are related to disease progression. | chicks with myeloblastic leukemia induced by avian myeloblastosis virus (amv) exhibited increased levels of plasma granulocyte/monocyte (gm) colony-stimulating activity (csa). chromatography of plasma from amv-infected chicks revealed that this csa eluted in the first protein peak from a column of sephadex g-200. a second protein peak from the same column contained an inhibitor of gm colony-formation. the presence of the inhibitor and the increased csa was studied during the development of myelo ... | 1982 | 6978259 |
| alterations of the conformation of the rnas of alfalfa mosaic virus upon binding of a few coat protein molecules. | structural changes in the single-stranded genome rnas (rnas 1, 2 and 3) and the subgenomic coat protein messenger (rna 4) of alfalfa mosaic virus upon addition of a few coat protein molecules of the virus were investigated by measuring the fluorescent intensity of bound ethidium bromide and by circular dichroism. no effect could be observed in the case of the genome rnas. however, in rna 4, which is of much less complexity than the genome rnas, a reduction of the ethidium bromide binding by 30% ... | 1982 | 7066325 |
| isolation and characterization of retrovirus-like elements from normal human fetuses. | retrovirus-like particles have been isolated from normal fetal human plasma and from different embryonic organs collected from late first-trimester fetuses. the majority of the virus-like particles banded at a density region of of 1.19-1.22 g/ml, although lighter particles having a density of 1.15-1.17 g/ml were observed in some fetal tissues. the particles appeared similar to retroviruses when viewed electron-microscopically. they contained reverse transcriptase (rt) which accepted oligo (dg)-p ... | 1982 | 7129678 |
| translational competition between related virus rna species in cell-free systems. | the competition between the rnas from two tobacco mosaic virus (tmv) strains for translation in rabbit reticulocyte lysate and wheat germ cell-free systems was investigated. the virus translational products were distinguished by the size difference of the i2 polypeptides. the rnas of the two strains were translated simultaneously if added to the translation system together at the beginning of the reaction. each of the tmv rnas could inhibit translation of the other when the reaction was initiate ... | 1982 | 7142974 |
| a monoclonal antibody with specificity for leukemic cells transformed by defective avian leukemia viruses. | mouse anti-chicken monoclonal antibodies were raised against an avian myeloblastosis virus (amv)-transformed myeloblastic leukemic cell line. one monoclonal antibody, s1-37 (igg2a), reacted with producer and nonproducer myeloblastic leukemia cell lines transformed by amv and by e-26 virus, but it did not react with chicken fibroblasts infected with rav-2, mav-2, mav-1, or rav-7. s1-37 also did not react with normal chicken hemopoietic cells, except for yolk sack macrophages and a small populatio ... | 1982 | 6302112 |
| nucleotide sequence and organization of the transforming region and large terminal redundancies (ltr) of avian myeloblastosis virus (amv). | avian myeloblastosis virus (amv) is a replication-defective acute leukemia virus, requiring a helper virus to provide the viral proteins essential for synthesis of new infectious virus. the genome of the amv has undergone a sequence substitution in which a portion of the region normally coding for the "env" protein has been replaced by chicken cellular sequences. these latter sequences are essential for the transforming activity of the virus. we have determined the complete nucleotide sequence o ... | 1982 | 6302118 |
| studies on the function of the non-primer trnas associated with the 70 s rna of avian myeloblastosis virus. | significant amounts of three trnas are associated with the 70 s rna of avian myeloblastosis virus (amv). the temperatures at which they are half dissociated from the 70 s rna in 50 mm nacl and their respective quantities relative to 35 s rna are: trnaarg, 51 degree c, 1.6; trnalys, 57 degree c, 0.7 and trnatrp, 76 degree c, 1.0. possible functions for the non-primer trnas (trnaarg and trnalys) were evaluated by determining the effect of their thermal dissociation on: (a) conversion of 70 s to 35 ... | 1982 | 6277384 |
| acute leukemia viruses e26 and avian myeloblastosis virus have related transformation-specific rna sequences but different genetic structures, gene products, and oncogenic properties. | replication-defective acute leukemia viruses e26 and myeloblastosis virus (amv) cause distinct leukemias although they belong to the same subgroup of oncogenic avian tumor viruses based on shared transformation-specific (onc) rna sequences. e26 causes predominantly erythroblastosis in chicken and in quail, whereas amv induces a myeloid leukemia. however, upon cultivation in vitro for >1 month, a majority of surviving hemopoietic cells of e26-infected animals bear myeloid markers similar to those ... | 1982 | 6285358 |
| proton-magnetic-resonance studies on the coat protein of alfalfa mosaic virus. | 1982 | 6290214 | |
| organization of chicken dna sequences homologous to the transforming gene of avian myeloblastosis virus. i. restriction enzyme analysis of total dna from normal and leukemic cells. | hybridization probes consisting of cloned dna recombinants which represent different regions of the leukemogenic sequence (amv) from avian myeloblastosis virus were used to carry out a more detailed restriction endonuclease analysis of the homologous sequences (proto-amv) present in normal and leukemic chicken dna. the results show that four large introns interrupt the normal cellular proto-amv sequences and that there is no major rearrangement of these sequences in leukemic myeloblasts. | 1982 | 6292519 |
| evidence that rna 4 of alfalfa mosaic virus does not replicate autonomously. | a mutant (tbts7) of alfalfa mosaic virus, the coat protein of which is unable to activate the viral genome (the rna species 1, 2, and 3, which need some coat protein for infectivity) at 30 degrees , can be rescued at this temperature by adding to the inoculum wild-type rna 3 (the genome part that contains the coat protein cistron), but not adding wild-type rna 4 (the subgenomic messenger for the coat protein). unless rna 3 of tbts 7 has a second ts mutation at a site not occurring in rna 4, it m ... | 1982 | 18635120 |
| molecular cloning of the complementary dna copies of the common and cowpea strains of tobacco mosaic virus rna. | complementary dna (cdna) copies of the common (om) and cowpea (cc) strains of tobacco mosaic virus (tmv) rna polyadenylated in vitro have been synthesized with amv reverse transcriptase and oligo (dt)10 as primer. the cdna was converted to a double-stranded form by e. coli dna polymerase i followed by s1 nuclease digestion. the double-stranded cdna copies were cloned in pbr322 at the psti site using the oligo(dc)-oligo(dg) tailing method. with the common strain, several clones containing inserts ... | 1982 | 18635128 |
| capped mrnas with reduced secondary structure can function in extracts from poliovirus-infected cells. | extracts from poliovirus-infected hela cells were used to study ribosome binding of native and denatured reovirus mrnas and translation of capped mrnas with different degrees of secondary structure. here, we demonstrate that ribosomes in extracts from poliovirus-infected cells could form initiation complexes with denatured reovirus mrna, in contrast to their inability to bind native reovirus mrna. furthermore, the capped alfalfa mosaic virus 4 rna, which is most probably devoid of stable seconda ... | 1982 | 14582204 |
| open reading frame in the minus strand of two plus type rna viruses. | : inspection of the nucleotide sequences of the rnas complementary to the coat protein mrnas from two plant viruses with a tripartite genome: alfalfa mosaic virus and brome mosaic virus, showed the presence of open reading frames for 138 and 118 amino acids, respectively. a third virus (cowpea chlorotic mottle virus) from the same family (1) does not show this phenomenon. this suggests that if a protein is coded for by the open reading frames it may be not essential for virus multiplication. alt ... | 1982 | 24317896 |
| lack of serological relationship between the 35k nonstructural protein of alfalfa mosaic virus and the corresponding proteins of three other plant viruses with a tripartite genome. | alfalfa mosaic virus rna 3 was translated in the mrna-dependent rabbit reticulocyte cell-free system. the 35k translational protein was partly purified and used to raise antibodies. the antibodies obtained reacted with the 35k protein directed by amv rna 3 but not with the corresponding proteins directed by rnas from three other viruses with a tripartite genome (tobacco streak, cucumber mosaic, and brome mosaic). | 1981 | 18635042 |
| evidence for the absence of swelling of alfalfa mosaic virions. | the stability of the quaternary structure of bottom and top components of alfalfa mosaic virus (respectively amv-b and amv-ta-t) in the ph range 5.5 to 7.8 and at ionic concentrations of 0.01 and 0.1 m has been investigated using small-angle x-ray scattering and photon correlation spectroscopy. the x-ray scattering curves show no significant changes over the angular range measured (to a resolution of 1 100 a (-1)) under the various solvent conditions; the radius of gyration of amv-ta-t is consta ... | 1981 | 18635037 |
| evidence that alfalfa mosaic virus infection starts with three rna-protein complexes. | the tripartite genome of alfalfa mosaic virus (amv) needs to be activated by its coat protein. to establish whether coat protein exerts its role by interacting structurally with one, two, or all three amv-rna species, the infectivity of mixtures of rna-protein complexes with free rnas were studied (smit and jaspars, virology 104, 454-461, 1980). these studies were not fully conclusive since some redistribution of coat protein does occur as soon as rnas are brought into contact with rna-protein c ... | 1981 | 18635065 |
| cloning a cdna for the pro-alpha 2 chain of human type i collagen. | poly(a)-rna enriched for type i procollagen sequences was isolated from normal human fibroblasts and used as template to synthesize double-stranded cdna with avian myeloblastosis virus (amv) reverse transcriptase. after the ends had been blunted with nuclease s1 and dgmp tails had been added with terminal deoxynucleotidyltransferase, the double-stranded cdna was annealed with pbr322 dna that had previously been cleaved with ecori, blunted with amv reverse transcriptase, and dcmp-tailed with term ... | 1981 | 6267597 |
| differential effects of transforming avian rna tumor viruses on avian macrophages. | functionally differentiated chicken macrophages were derived by in vitro differentiation of embryonic yolk sac cells and were characterized by several macrophage-specific cell markers. uniform, infected, virus-producing cultures were obtained after exposure of these macrophages to avian myoblastosis virus (amv), avian myelocytomatosis virus (mc29), myeloblastosis-associated virus (mav-2), and prague strain of rous sarcoma virus (pr-b rsv). both amv and mc29 induced morphological transformation t ... | 1981 | 6267600 |
| amino acid sequence of p15 from avian myeloblastosis virus complex. | the complete amino acid sequence of the p15 gag protein from avian myeloblastosis virus (amv) complex has been determined by sequential edman degradation of the intact molecule and of peptide fragments generated by limited tryptic cleavage, cleavage with staphylococcal protease, and cyanogen bromide cleavage. amv p15 is a single-chain protein containing 124 amino acids. the charged amino acids tend to be clustered in the primary structure. p15 contains a single cysteine at position 113 which may ... | 1981 | 6268146 |
| terminal uridylyl transferase of vigna unguiculata: purification and characterization of an enzyme catalyzing the addition of a single ump residue to the 3'-end of an rna primer. | an enzyme which catalyzes the addition of a single ump residue from utp to the 3'-end of an rna primer and which is referred to as terminal uridylyl transferase (tut) has been extensively purified from the membrane fraction of vigna unguiculata leaves. the purification procedure involved (i) solubilization by cation depletion (ii) deae-sepharose cl-6b column chromatography (iii) affinity chromatography of poly(u)-sepharose 4b and (iv) glycerol gradient centrifugation. the molecular weight of the ... | 1981 | 6269049 |
| in vitro translation of avian myeloblastosis virus rna. | avian myeloblastosis virus (amv)-infected cells contain two viral mrna's, a genome-sized 34s (7.5-kilobase) mrna and a 21s (2.5-kilobase) subgenomic mrna, which contains the amv-specific sequences (myb sequences). we found that amv virions packaged both the 7.5-kilobase full-length genomic rna and the 2.5-kilobase subgenomic rna. in vitro translation of amv virion rna sized by sucrose density gradient centrifugation yielded 76,000-, 56,000-, 48,500-, 47,000-, and 32,000-dalton products. the 76,0 ... | 1981 | 6270366 |
| vertebrate dnas contain nucleotide sequences related to the transforming gene of avian myeloblastosis virus. | avian myeloblastosis virus contains a continuous sequence of approximately 1,000 nucleotides which may represent a gene (amv) responsible for acute myeloblastic leukemia in chickens. this sequence appears to have been acquired from chicken dna and to be substituted for the envelope gene in the viral genome. we used hybridization probes enriched for the amv sequences and conditions that facilitate annealing of partially homologous nucleotide sequences to show that cellular sequences related to am ... | 1981 | 6275098 |
| electron microscopic characterization of avian myeloblastosis virus rna by the non-protein technique of spreading. | the quantitative analysis of the behaviour of retroviral rna (amv rna) under the conditions of the non-protein technique of electron microscopic visualization on a mono-molecular film of bac was performed. this technique resulted in visualization of intact molecules the mean length of which was 12% larger in comparison with molecules spread by the cytochrome c method. the method was found to be extremely sensitive to the surface properties of the supporting membrane which distinctly affect the s ... | 1981 | 6276235 |
| binding of ribosomes to the 5' leader sequence (n = 258) of rna 3 from alfalfa mosaic virus. | rna 3 of alfalfa mosaic virus (almv) contains information for two genes: near the 5' end an active gene coding for a 35 kd protein and, near the 3' end, a silent gene coding for viral coat protein. we have determined a sequence of 318 nucleotides which contains the potential initiation codon for the 35 kd protein at 258 nucleotides from the 5' end. this long leader sequence can form initiation complexes containing three 80 s ribosomes. a shorter species of rna, corresponding to a molecule of rna ... | 1981 | 7232211 |
| an investigation of the structure of alfalfa mosaic virus by small-angle neutron scattering. | 1981 | 7265211 | |
| effects of ethylating agents on dna synthesis in vitro: implications for the mechanism of carcinogenesis. | a highly carcinogenic ethylating agent, ethylnitrosourea (enu), and a weakly carcinogenic one, diethylsulfate (des) react with dna to roughly the same extent but des produces about 6 times as many unstable ethylated bases, which are gradually lost spontaneously under physiological conditions. the different rates of loss for the different dna bases have been studied using polydeoxyribonucleotides. spontaneous strand breakage following base loss is slow, lagging more than a week behind base loss a ... | 1981 | 7273319 |
| crystallization of alfalfa mosaic virus coat protein as a t = 1 aggregate. | 1981 | 7299819 | |
| an electron microscopic investigation of the structure of alfalfa mosaic virus. | 1981 | 7265214 | |
| improved elisa conditions for detection of plant viruses. | clover yellow vein virus (cyvv) and homologous antisera were used to test effects of time and temperature on enzyme-linked immunosorbent assay (elisa) in polystyrene substrate plates. replicated lattice square and youden square experimental designs were used to measure and account for variation in absorption values associated with sample position within polystyrene plates. adsorption of coating antibody to polystyrene was relatively rapid, reaching optimum assay efficiency in 1 h at 5 degrees c ... | 1981 | 7021575 |
| characterization of an inhibitor of granulocyte/monocyte colony formation in leukemic chicken plasma. | the plasma of chicks with myeloblastic leukemia (induced by avian myeloblastosis virus, amv) contained an inhibitor which blocked colony formation in vitro by marrow cells. it eluted in the second protein peak obtained by sephadex g-200 gel filtration and was found in the diafiltrate following defiltration through a um 10 membrane under acidic conditions. it was not extractable with chloroform, was heat-stable (65 degrees c, 30 min), pronase-sensitive and had a molecular weight less than or equa ... | 1981 | 6165604 |
| properties of the avian viral protein p12. | the avian rna tumour virus structural protein p12 was purified from avian myeloblastosis virus (amv) by nucleic acid affinity chromatography to apparent homogeneity as judged from sds--polyacrylamide gel electrophoresis. a filter binding assay was used for the identification of p12. high concentrations of p12 precipitated nucleic acids out of solution in the absence of mgcl2. binding of p12 to single-stranded nucleic acids protected them from digestion with nucleases and resulted in a hyperchrom ... | 1981 | 6169796 |
| heterogeneous chromatographic behaviour or soluble rna replicase from healthy and virus-infected tobacco leaves: an improvement of the purification methodology. | during purification of soluble rna replicase from healthy and alfalfa mosaic virus-infected tobacco leaves, crude extracts were chromatographed on deae-sephadex a-25, and three rna-dependent rna polymerase activities were obtained; one of these was previously characterized as a true rna replicase, the remaining two were not studied (chifflot et al., 1980, virology 100, 91). we now demonstrate that all of these activities correspond to the same rna replicase, complexed or not to cellular or viral ... | 1981 | 6173393 |
| the genome and the intracellular rnas of avian myeloblastosis virus. | avian myeloblastosis virus (amv) is an acute leukemia virus which causes a myeloblastic leukemia in birds and transforms myeloid hematopoietic cells in vitro. we have analyzed rna from amv virions and from amv-transformed producer and nonproducer cells by gel electrophoresis followed by transfer to chemically activated paper and hybridization to several complementary dna (cdna) probes. using a cdna probe specific for amv, we identified two rna species of 7.2 and 2.3 kb, which were present in all ... | 1981 | 6260378 |
| analysis of avian myeloblastosis viral rna and in vitro synthesis of proviral dna. | two virus-specific rna species of 7.5 and 7.0 kilobases have been identified in avian myeloblastosis virus (amv) by denaturing gel electrophoresis and blot hybridization analysis, and they were found to be in a 10:1 ratio. the individual rnas direccted the cell-free synthesis of the 76,000-dalton "gag" protein and the 180,000-dalton "gal-pol" protein, thereby demonstrating 5' sequence homology of approximately 4.9 kilobases between the two species. synthesis of these two precursor proteins by th ... | 1981 | 6264460 |
| size and genetic content of virus-specific rna in myeloblasts transformed by avian myeloblastosis virus (amv). | 1981 | 6259824 | |
| intraspecies variability in transmission efficiency of stylet-borne viruses by the pea aphid (acyrthosiphon pisum). | the efficiency of bean yellow mosaic virus (bymv; potyvirus group) tranasmission from pea to pea plants by 36 clones of the pea aphid (acyrthosiphon pisum) was studied. the efficiency of the clones varied; it was not related to the aphid colour form (green, red or yellow) or the origin of the clone (host plant, geographic area). with alfalfa mosaic virus, the virus-vector relationships concerning transmission efficiency were, in general, similar to those found with bymv. the behaviour of the clo ... | 1980 | 6108064 |
| reactivity of reverse transcriptase toward (s4u,u)n copolymers and spin-labeled nucleic acid lattices. | spin-labeled copolymers of 4-thiouridine and uridine (ls4u,u)n] that contain various amounts of spin label (l) were synthesized by either (i) chemical alkylation of the 4-thiouridine-uridine copolymers (s4u,u)n prepared by copolymerizing 4-thiouridine 5'-diphosphate (s4udp) and udp or (ii) copolymerization of spin-labeled s4udp with udp using polynucleotide phosphorylase. the effect of (s4u,u)n and (ls4u,u)n on avian myeloblastosis virus (amv) rna-dependent dna polymerase (rna-dependent dna nucl ... | 1980 | 6159632 |
| genetic structure of avian myeloblastosis virus, released from transformed myeloblasts as a defective virus particle. | chicken myeloblasts transformed by avian myeloblastosis virus (amv) in the absence of nondefective helper virus (termed nonproducer cells) were found to release a defective virus particle (dvp) that contains avian tumor viral gag proteins but lacks envelope glycoprotein and a dna polymerase. nonproducer cells contain a pr76 gag precursor protein and also a protein that is indistinguishable from the pr180 gag-pol protein of nondefective viruses. the rna of the dvp is 7.5 kilobases (kb) long and i ... | 1980 | 6159639 |
| nucleotide sequence of the putative recognition site for coat protein in the rnas of alfalfa mosaic virus and tobacco streak virus. | the sequence of the 3'-terminal 180 and 140 nucleotides of rnas 2 and 3, respectively, of tobacco streak virus (tsv) was deduced by reverse transcription in the presence of a specific primer and chain terminators. homology between the two rnas was found to be restricted to a 3-terminal region of about 45 nucleotides. the data were compared with the sequence of the homologous region of 145 nucleotides occurring at the 3'-termini of the alfalfa mosaic virus (a1mv) rnas, which contains the specific ... | 1980 | 6160470 |
| cellular sequences are present in the presumptive avian myeloblastosis virus genome. | ecori restriction endonuclease fragments from a lambda proviral dna hybrid containing the entire presumptive avian myeloblastosis virus (amv) provirus, and from a lambda proviral hybrid containing a partial myeloblastosis-associated virus type 1 (mav-1)-like provirus were compared by heteroduplex analysis. the cloned presumptive amv provirus was also analyzed by electron microscopy, using r-loop formation with purified 35s rna isolated from virions of the standard amv complex. the results indica ... | 1980 | 6254063 |
| expression of endogenous avian myeloblastosis virus information in different chicken cells. | uninfected chicken cells were found to contain endogenous avian myeloblastosis virus (amv)-specific information. different tissues from chicken embryos and chickens expressed different amounts of the amv-specific information. the endogenous amv-related rna was most abundant in bone marrow cells, which contained about 20 copies per cell. about 5 to 10 copies of amv endogenous rna per cell were found in embryonic yolk sac cells and bursa cells. the spleen, muscle, liver, and kidney cells of chicke ... | 1980 | 6255203 |
| identification of a proviral genome associated with avian myeloblastic leukemia. | we have identified and isolated a presumptive leukemogenic provirus from myeloblasts of a chicken in which leukemia had been induced by avian myeloblastosis virus (amv). leukemic myeloblasts isolated from peripheral blood or from converted yolk sac cultures of various strains of chickens, regardless of the endogenous proviral content or amv pseudotype used for infection, contain an ecori 2.2-megadalton (mdai) and a hindiii 2.6-mdal proviral fragment. a proviral genome flanked by chicken dna sequ ... | 1980 | 6248880 |
| detection of viral markers and incomplete viral genome rescue from asv transformed rodent cells. | two non-virogenic rat cell lines twerc and fr transformed with pr-rsv and fsv, respectively, were analyzed. both these cell lines contained vrna, but only in twerc cells was the major viral polypeptide p27 synthetized. transforming virus can be rescued from both cell lines only after fusing them with chicken fibroblasts preinfected with avian leukosis viruses of subgroup a, c, d, f and both td mutants of pr-rsv-c and b77-c. similarly, virus was rescued in experiments in which qef infected with r ... | 1980 | 6250919 |
| detection of avian oncovirus group-specific antigens by the enzyme-linked immunosorbent assay. | a three-step sandwich enzyme-linked immunosorbent assay was developed for the detection of avian oncovirus group-specific (gs) antigens. the assay procedure was to coat the wells of microtitre plates with hamster anti-gs igg, react with crude or purified antigen and finally with hamster anti-gs igg linked to horseradish peroxidase. the sensitivity was 8 picograms (pg) of input avian myeloblastosis virus (amv) protein, with negligible background. as the elisa takes less than 2 h to perform, large ... | 1980 | 6245172 |
| avian retroviruses that cause carcinoma and leukemia: identification of nucleotide sequences associated with pathogenicity. | avian myelocytomatosis virus (mc29v) is a retrovirus that transforms both fibroblasts and macrophages in culture and induces myelocytomatosis, carcinomas, and sarcomas in birds. previous work identified a sequence of about 1,500 nucleotides (here denoted onc(mcv)) that apparently derived from a normal cellular sequence and that may encode the oncogenic capacity of mc29v. in an effort to further implicate onc(mcv) in tumorigenesis, we used molecular hybridization to examine the distribution of nu ... | 1980 | 6245277 |
| isolation of complementary dna unique to the genome of avian myeloblastosis virus (amv). | 1980 | 6245521 | |
| target cell specificity of defective avian leukemia viruses: hematopoietic target cells for a given virus type can be infected but not transformed by strains of a different type. | defective avian leukemia viruses of the avian erythroblastosis (aev), avian myelocytomatosis (mc29), and avian myeloblastosis (amv) type induce the proliferation of leukemic cells with properties of erythroblasts, macrophages, and myeloblasts, respectively. their target cells can be separated and have properties of cells of the erythroid (aev) and myeloid lineage (mc29 and amv), respectively. in the present study we have shown that this target cell specificity is not due to the ability of the di ... | 1980 | 6244556 |
| characterization of avian myeloblastosis-associated virus dna intermediates. | the major species of unintegrated linear viral dna identified in chicken embryonic fibroblasts infected with either the avian myeloblastosis-associated viruses (mav-1, mav-2) or the standard avian myeloblastosis virus complex (amv-s) has a mass of 5.3 x 10(6) daltons. an additional minor dna component observed only in amv-s-infected cells has a mass of 4.9 x 10(6) daltons. the unintegrated linear viral dnas and integrated proviruses of mav-1 and mav-2 have been analyzed by digestion with the res ... | 1980 | 6246269 |
| identification of the avian myeloblastosis virus genome. ii. restriction endonuclease analysis of dna from lambda proviral recombinants and leukemic myeoblast clones. | two lambda proviral dna recombinants were characterized with a number of restriction endonucleases. one recombinant contained a complete presumptive avian myeloblastosis virus (amv) provirus flanked by cellular sequences on either side, and the second recombinant contained 85% of a myeloblastosis-associated virus type 1 (mav-1)-like provirus with cellular sequences adjacent to the 5' end of the provirus. comparing the restriction maps for the proviral dnas contained in each lambda hybrid showed ... | 1980 | 6253659 |
| enzymatic activities associated with avian and murine retroviral dna polymerases. catalysis of and active site involvement in pyrophosphate exchange and pyrophosphorolysis reactions. | reverse transcriptase isolated from avian myeloblastosis virus (amv) and rauscher murine leukemia virus (rlv) were examined for their ability to catalyze polymerization, ribonuclease h, pyrophosphate exchange, and pyrophosphorolysis reactions. a detailed characterization and a study of requirements for the expression of pyrophosphate exchange and pyrophosphorolysis reactions indicated that a variety of rna and dna template-primers supported these catalytic reactions. furthermore, hydrogen bondin ... | 1980 | 6153389 |
| recombinant plasmids containing avian vitellogenin structural gene sequences derived from complementary dna. | purified mrna coding for chicken vitellogenin, a precursor of egg yolk proteins, was transcribed to complementary dna (cdnavit) with avian myeloblastosis virus (amv) reverse transcriptase. double-stranded cdna was synthesized with escherichia coli dna polymerase i (fragment a) using the self priming ability of the cdna. following s1 nuclease digestion the double-stranded cdna was inserted into the hind iii site of plasmid pbr322 using the poly(da) . poly(dt) tailing method, and the hybrid molecu ... | 1980 | 6986172 |
| phenylglyoxal as a template site-specific reagent for dna and rna polymerases. selective inhibition of initiation. | phenylglyoxal, an arginine-specific reagent, strongly inhibits dna polymerases isolated from eukaryotic, prokaryotic, and rna tumor viral sources as well as escherichia coli rna polymerase. the inhibitory action of phenylglyoxal appears to be due to interference with the template binding function of these enzymes and implies the presence of an arginine residue at the template binding site of these enzymes from diverse sources and suggests that template dependent dna, and perhaps rna polymerases, ... | 1980 | 6985908 |
| nucleotide sequences at the 5'-termini of the alfalfa mosaic virus rnas and the intercistronic junction in rna 3. | nucleotide sequences at the 5'-termini of the alfalfa mosaic virus genomic rnas and the intercistronic junction in rna 3 were deduced and compared to identify possible common recognition signals for replicating enzymes in the corresponding minus-stranded viral rnas. homology between the 5'-terminal sequences is less than 11 nucleotides and no complementarity with the homologous sequence occurring at the 3'-end of the viral rnas was observed. homology between the 5'-terminus and intercistronic re ... | 1980 | 6927843 |
| application of band centrifugation to the study of the assembly of alfalfa mosaic virus. | 1980 | 7357070 | |
| complete nucleotide sequence of alfalfa mosaic virus rna 4. | alfalfa mosaic virus rna 4, the subgenomic messenger for viral coat protein, was partially digested with rnase t1 or rnase a and the sequence of a number of fragments was deduced by in vitro labeling with polynucleotide kinase and application of rna sequencing techniques. from overlapping fragments, the complete primary sequence of the 881 nucleotides of rna 4 was constructed: the coding region of 660 nucleotides (not including the initiation and termination codon) is flanked by a 5' noncoding r ... | 1980 | 7433090 |
| complexes of alfalfa mosaic virus rna 4 with one and three coat protein dimers. | rna 4, the subgenomic coat protein messenger of alfalfa mosaic virus, was loaded with small amounts of coat protein in a reaction in which complete virions were the protein donor. in such a reaction the protein subunits attach to the high-affinity binding sites near the 3' end of rna 4 [houwing, c. j., & jaspars, e. m. j. (1978) biochemistry 17, 2927-2933]. at a ratio of up to 13 coat protein subunits to 1 mol of rna 4, complexes with one and three protein dimers, designated complex i and comple ... | 1980 | 7448167 |
| sequence homology at the 3'-termini of the four rnas of alfalfa mosaic virus. | 1980 | 7353626 | |
| glycoprotein and protein composition of bovine leukemia virus (blv). | highly purified preparation of bovine leukemia virus (blv) was obtained by the method described in this communication. blv was isolated from cell-free culture medium, harvested from blv-producing cell-line flk. polyacrylamide gel electrophoresis of blv proteins and glycoproteins, in comparison with avian myeloblastosis virus (amv), confirmed high purity of blv preparations. molecular weights of some blv-proteins and glycoproteins were calculated. by employing polyacrylamide gradient 5 to 30% it ... | 1980 | 6265814 |
| preferential binding of 3'-terminal fragments of alfalfa mosaic virus rna 4 to virions. | 3'-terminal fragments present in a partial ribonuclease t1 digest of rna 4 of alfalfa mosaic virus were selectively bound to virions of the same virus by incubation in 10 mm sodium phosphate and 1 mm edta, ph 7.0. the virions with the associated fragments were separated from the remainder of the digest by velocity gradient centrifugation. when the incubation was performed in 27.7 mm na2hpo4 and 6.2 mm citric acid, ph 6.8, plus 10% glycerol, much more, but less specific, binding was obtained. how ... | 1980 | 6778502 |
| [dna polymerase in the microsomal fraction of the myeloblasts of chickens infected with avian myeloblastosis virus]. | only one dna polymerase is present in the microsomal fraction of the cells producing amv. chromatographically purified enzyme shows the properties of revertase, that is it transcribes in dna the information encoded in natural rna. the enzyme possesses identical chromatographic characteristics and the same template specificity as the enzyme isolated from pure amv virus. thus the virus enzyme and the cellular dna polymerase from the microsomal fraction cannot be differentiated on the basis of cert ... | 1980 | 7293688 |
| synthesis and characterization of dna complementary to carnation mottle virus rna. | dna complementary to carnation mottle virus-rna (carmv rna) was synthesized using the reverse transcriptase of avian myeloblastosis virus (amv) as enzyme, and an hydrolysate of calf thymus dna as primer. after purification steps that included self-annealing and hydroxyapatite chromatography, the dna transcript was more than 99% sensitive to s1 nuclease and hybridized to at least 92% of the carmv-rna sequences, but not to heterologous rna. therefore, the purified transcript was single stranded an ... | 1980 | 18631672 |
| limited sequence variation in the leader sequence of rna 4 from several strains of alfalfa mosaic virus. | the sequences of the 5'-noncoding regions of rna 4 of seven strains of alfalfa mosaic virus were compared. in each case, the coat protein cistron was preceded by a leader sequence of 39 nucleotides (including the initiator codon). at position 26, an a-, g-, or u-residue was found. otherwise the leader sequences are identical. | 1980 | 18631714 |