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deoxyribonucleic acid homology and taxonomy of agrobacterium, rhizobium, and chromobacterium.hybridization experiments were carried out between high molecular weight, denatured, agar-embedded deoxyribonucleic acid (dna) and homologous, nonembedded, sheared, denatured (14)c-labeled dna from a strain of agrobacterium tumefaciens and rhizobium leguminosarum (the reference strains) in the presence of sheared, nonembedded, nonlabeled dna (competing dna) from the same or different nomen-species of agrobacterium, rhizobium, chromobacterium, and several other organisms. percentage of dna homolo ...19674961629
induction of adventitious roots by culture filtrates of the hairy root bacterium, agrobacterium rhizogenes. 19715156939
involvement of a plasmid in the hairy root disease of plants caused by agrobacterium rhizogenes. 1979231271
hairy root: plasmid encodes virulence traits in agrobacterium rhizogenes.agrobacterium rhizogenes strain 15834, which incites hairy root disease in plants, harbors three large plasmids: par15834a (107 x 10(6) daltons), par15834b (154 x 10(6) daltons), and par15834c (258 x 10(6) daltons). kanamycin-resistant transconjugants were selected in a cross of kanamycin-resistant derivate of strain 15834 and an avirulent recipient. the transconjugants belonging to one class were virulent and contained all three donor plasmids. these transconjugants also acquired sensitivity to ...19806245060
relationship of plasmids responsible for hairy root and crown gall tumorigenicity.three strains of agrobacterium rhizogenes were examined for plasmids. strains 15834 and a4 contained essentially identical large plasmids, par15834c and para4c, respectively (approximately 260 x 10(6) daltons). these plasmids can dissociate to two smaller plasmid species. strain tr105 contained only a single plasmid, which was homologous with the dissociation product of par15834c, par15834b. plasmid par15834c shared little overall sequence homology with other ti plasmids. one region of conserved ...19807430069
tumor formation and rhizogenicity of agrobacterium rhizogenes carrying ti plasmids.octopine ti plasmids were introduced into different agrobacterium rhizogenes strains. transconjugants became able to utilize octopine and to induce aberrant tumors, the surface of which was all covered wioth roots of different size and morphology. the plasmids endogenous in a. rhizogenes were shown to be compatible with incrh-1 ti plasmids.19807439687
fingerprinting and sequence homology of plasmids from different virulent strains of agrobacterium rhizogenes. 19816264521
method for the transfer of large cryptic, non-self-transmissible plasmids: ex planta transfer of the virulence plasmid of agrobacterium rhizogenes. 19826292973
regions of homology between tumorigenic plasmids from agrobacterium rhizogenes and agrobacterium tumefaciens. 19827089090
tumor induction by agrobacterium rhizogenes involves the transfer of plasmid dna to the plant genome.the dna from tumors of nicotiana glauca initiated by strains of agrobacterium rhizogenes was shown to contain sequences that are homologous to the root-inducing (ri) plasmid of the bacterium. two independently established tumor lines contained a similar portion of the ri-plasmid. the ri-plasmid also hybridized to dna fragments from uninfected n. glauca. a cosmid clone of the ri-plasmid encompassing the region containing the ri-plasmid sequences that are stably transferred to the plant also hybri ...198216593190
crown gall disease and prospects for genetic manipulation of plants.agrobacterium tumefaciens incites crown gall tumors when bacterial dna integrates into plant nuclear dna. plant cells can express these integrated bacterial genes. following insertion of desired genes into bacterial dna using recombinant dna techniques, this system permits introduction of these new genes into plant dna. we discuss the potential for genetic manipulation of plants using agrobacterium tumefaciens and the related organism agrobacterium rhizogenes.198217807126
identification of t-dna in the root-inducing plasmid of the agropine type agrobacterium rhizogenes 1855.the region of the virulence plasmid of the agropine type agrobacterium rhizogenes 1855 (pri-1855) which is transferred to plant cells upon infection (t-dna) has been identified by means of southern blot hybridizations with the t-dna of the mannopine type a. rhizogenes 8196. the presence in the plant genome of the pri-1855 sequences thus identified is demonstrated in carrot roots derived from infection with strain 1855. the t-dna of pri-1855 has been mapped by means of cloned eco ri partial diges ...198224318035
restriction endonuclease mapping of the root-inducing plasmid of agrobacterium rhizogenes 1855.the root-inducing plasmid of the agropine type agrobacterium rhizogenes 1855 was mapped by means of the restriction endonuclease ecori. the circular arrangement of the more than 60 fragments generated by this enzyme was established by electrophoretic analysis of pbr322 clones harboring overlapping segments of pri1855 derived by partial digestion with ecori. a large region of the plasmid comprising the t-dna was mapped with two additional enzymes, bamhi and hindiii, by means of southern blot hybr ...19836314408
structure of t-dna in roots transformed by agrobacterium rhizogenes.dna isolated from hairy roots incited on daucus carota by agrobacterium strains harboring the ri plasmid was probed with ri plasmid fragments to identify plasmid sequences transferred and integrated into the plant genome. one hairy root line was incited by an a. rhizogenes natural isolate strain harboring two large plasmids in addition to the ri plasmid. dna from hairy roots incited by this strain contained a total of five nonidentical copies of t-dna which together comprised a t-dna complement ...19836875427
transformation of several species of higher plants by agrobacterium rhizogenes: sexual transmission of the transformed genotype and phenotype.the t-dna of the ri plasmid from agrobacterium rhizogenes is compatible with the regeneration of whole plants from genetically transformed roots and is transmitted through meiosis to the progeny of genetically transformed plants in carrot, tobacco, and morning glory (convolvulus arvensis). the presence of ri t-dna is correlated with a phenotype that in some respects is invariable from species to species and in other respects varies as a function of species, organ clone within species, or individ ...19846744417
physical map of the agrobacterium rhizogenes strain 8196 virulence plasmid.virulence of agrobacterium rhizogenes, agent of hairy root disease, is conferred by large plasmids called ri (root-inducing) plasmids. we have determined the bamhi fragment map of pri8196, mw 143 mda, principally by analysis of recombinant plasmids containing overlapping bamhi partial-digest fragments. clones containing solitary bamhi inserts of remaining unmapped fragments were used to probe a series of southern-blotted, pri8196-derived ecori, psti, hindiii, sali, or smai digests. continguous h ...19846324259
hairy-root-inducing plasmid: physical map and homology to tumor-inducing plasmids.a physical map was constructed for the 250-kilobase plasmid pria4b, which confers the virulence properties of a strain of agrobacterium rhizogenes for hairy root disease in plants. the complete hindiii and kpni restriction map was determined from a collection of overlapping hindiii partial digest clones. homologous regions with two well-characterized plasmids that confer virulence for crown gall disease, plasmids ptia6 and ptit37, were mapped on pria4b. as much as 160 kilobases of pria4b had det ...19846690423
the t-dna of agrobacterium rhizogenes is transmitted through meiosis to the progeny of hairy root plants.plants regenerated from tobacco hairy root callus cultures were fertilized by self-pollination, and healthy, morphologically normal r1 offspring were obtained. three of these r1 seedlings were analyzed for the presence of t-dna and synthesis of the t-dna-specific compound agropine. all three r1 plants analyzed contained the same full-length t-dna as the parental regenerant, while only two showed agropine synthesis.19846090564
restriction map of an agropine-type ri plasmid and its homologies with ti plasmids.the ri plasmid of an agropine-type agrobacterium rhizogenes, strain hri, was cloned in a cosmid and mapped with the restriction endonucleases bamhi, ecori, kpni, smai, and xbai. this plasmid is almost identical to pri1855 and pria4b. a study by southern hybridizations of the homologies with octopine ptib6806 and nopaline ptic58 makes it possible to propose the localization of certain functions on this plasmid, such as virulence, agropine catabolism, agropine synthesis, and the origin of replicat ...19846095353
localization of agropine-synthesizing functions in the tr region of the root-inducing plasmid of agrobacterium rhizogenes 1855.the region of the ri plasmid pri 1855 that encodes agropine synthesis has been identified through its sequence homology with the equivalent genes of the octopine ti plasmid pti ach5. interestingly the agropine genes lie outside the so-far identified t-dna of pri 1855, and are separated from this latter by a long sequence of non integrated plasmid dna. the presence of this additional t-dna (tright dna) in hairy roots was demonstrated by southern blot analysis and by the presence of specific trans ...19853991808
molecular and genetic analysis of the transferred dna regions of the root-inducing plasmid of agrobacterium rhizogenes.the t-dna regions of the root-inducing (ri) plasmid pria4b of agrobacterium rhizogenes were characterized. two regions, designated tl-dna and tr-dna, were found to be integrated and stably maintained in the plant genome. the tl-dna spanned a 15- to 20-kilobase region of pria4b and was separated from the tr-dna region by at least 15 kilobases of nonintegrated plasmid dna. the tr-dna region also spanned a 15- to 20-kilobase region of pria4b and included a region of homology to the tms morphogenic ...19854044524
heterologous hybridization of bacterial dna to the endoglucanases a and b structural genes cela and celb of clostridium thermocellum.dna from various cellulolytic and non-cellulolytic bacteria was found to hybridize to clostridium thermocellum ncib10682 dna fragments carrying the structural genes cela and celb which code for endoglucanases a and b. homology to cela was detected in agrobacterium rhizogenes, azospirillum brasilense, bacillus subtilis, cellulomonas sp., clostridium stercorarium, erwinia chrysanthemi, pseudomonas solanacearum and streptomyces griseus. homology to celb was detected only in b. subtilis, c. stercora ...19854083831
lacz gene fusions and insertion mutagenesis in the tl-region of agrobacterium rhizogenes ri plasmid.agrobacterium rhizogenes induces root formation and inserts a fragment of its plasmid into the genome of infected plants. a part of the transferred region (tl-region) of the ri plasmid of a. rhizogenes strain a4 was cloned in pbr322. insertions of the escherichia coli lacz coding region into the hybrid plasmids were made in vivo using mini-mu-duction. two mini-mus were used, one with the mu a and b transposase genes (mudii1681) and the other without (mudii1734). two inserts which result in e. co ...19852994128
structure and expression of ri t-dna from agrobacterium rhizogenes in nicotiana tabacum. organ and phenotypic specificity.the incorporation of transferred dna (t-dna) from the ri plasmid of agrobacterium rhizogenes into the chromosomal dna of higher plants is correlated with the appearance of a complex phenotype. the transformed genotype and phenotype undergo mendelian inheritance. through studies of ri t-dna content and transcription in nicotiana tabacum, we have delineated a particular part of this foreign dna as the likely source of the transformed phenotype. one inducible/repressible aspect of the transformed p ...19852419571
genotypic variability of soybean response to agrobacterium strains harboring the ti or ri plasmids.twenty four diverse cultivars of soybean (glycine max [l.] merrill) and three lines of its annual wild progenitor glycine soja sieb and zucc. were tested for their response to agrobacterium strains harboring either the ti (tumor-inducing) plasmid (pti) from agrobacterium tumefaciens or the ri (root-inducing) plasmid (pri) from agrobacterium rhizogenes following uniform wounding and inoculation. based upon gall weight at 8 weeks postinfection, three g. max cultivars (biloxi, jupiter, and peking) ...198516664035
isolation and identification of tl-dna/plant junctions in convolvulus arvensis transformed by agrobacterium rhizogenes strain a4.we have constructed a charon 4a phage library containing insert dna isolated from a morning glory (convolvulus arvensis) plant (clone 7) regenerated from a root organ culture incited by agrobacterium rhizogenes, strain a4. using a subcloned region of the ri plasmid as p-labeled probe, two lambda clones containing most of the 'left' t-dna (tl) region were isolated. one of these lambda clones contains the left tl-dna/plant junction, which was located by comparing nucleotide sequences from the appr ...198516453649
a study of karyotypes and their alterations in cultured and agrobacterium transformed roots of lycopersicon peruvianum mill.organ culture, plant regeneration from callus culture, and hairy root disease caused by agrobacterium rhizogenes were utilized as methods of rapid in vitro propagation in lycopersicon peruvianum mill. a detailed and comparative karyotype analysis of the resulting material under such in vitro conditions revealed karyotypic stability under organ culture method, ploidy change in callus derived plants, and minor structural alterations of chromosomes in roots transformed by a. rhizogenes.198524247391
identification of the genetic locus responsible for non-polar root induction by agrobacterium rhizogenes 1855.root proliferation can be induced by agrobacterium rhizogenes on carrot discs both on the apical and basal surface (facing the root apex and base, respectively) or on the apical surface only, depending on the bacterial strain. this differential response on the two surfaces is denominated polarity. we correlate the polarity of some strains with the absence of an ri plasmid genetic locus, present in non polar strains such as a. rhizogenes 1855, which bears sequence homology with the auxin genes of ...198524306992
genetic modification of potato development using ri t-dna.forty-two potato plants were regenerated from a hairy-root line obtained after infection of a shoot of solanum tuberosum cv 'desiree' with agrobacterium rhizogenes strain lba 9402 (pril855). transformed plants were uniform and had a distinct phenotype and development compared with untransformed controls. their growth was vigorous, especially early in their development, their roots were abundant and showed reduced geotropism, their leaves were slightly crinkled and glossy and they produced longer ...198524253018
infection of turnip and radish storage roots with agrobacterium rhizogenes.within about 10 days after inoculation with agrobacterium rhizogenes, the vascular bundles of storage root disks of turnip or radish developed small outgrowths with numerous root hairs. thereafter, adventitious roots (hairy roots) emerged extensively from these outgrowths. the hairy roots which emerged fully supported the growth of host plants, though they lacked geotropism. an excised hairy root could be subcultured as an axenic root culture in the absence of phytohormones. hairy root cultures ...198524253688
identification of hairy root loci in the t-regions of agrobacterium rhizogenes ri plasmids.agrobacterium rhizogenes induces root formation at the wound site of inoculation in plants and inserts a fragment of its plasmid (ri) into the plant nuclear dna. parts of the transferred region (t-region) of the ri plasmid of a. rhizogenes strain a4 or 8196 are cloned in escherichia coli. insertions of the e. coli lacz coding region into the hybrid plasmids were made in vivo using transduction by minimu. twenty insertions localized in the tl-dna of pria4 (or pri1855) and 2 inserts in the t-dna o ...198624307326
tl-dna from agrobacterium rhizogenes plasmid pri1855 reduces the osmotic pressure in transformed plants grown in vitro.growth, water content, osmotic pressure and solute content were examined for normal potato (solanum tuberosum l. cv. desiree) and a derivative (line d9x8a), which was genetically transformed with tl-dna from agrobacterium rhizogenes. plants were grown (i) in vitro, (ii) in a growth chamber and (iii) in the field. in vitro, the transformed potato plants produced more biomass than the untransformed plants, partly because they had a higher water content. potassium concentration and osmotic pressure ...198624233742
secondary product formation by cultures of beta vulgaris and nicotiana rustica transformed with agrobacterium rhizogenes.'hairy root' cultures of beta vulgaris and nicotiana rustica were established after roots were induced on plants following infection with agrobacterium rhizogenes. the transformed cultures of b. vulgaris and n. rustica synthesised their characteristic secondary products, the betalain pigments and nicotine alkaloids respectively, at levels comparable with those of in vivo roots from the same variety. betalains were entirely retained inside the root tissue. in contrast, a proportion of the nicotin ...198624248047
transformation of solanum nigrum l. protoplasts by agrobacterium rhizogenes.solanum nigrum protoplasts were co-cultivated with agrobacterium rhizogenes harboring agropine-type ri plasmid (pri15834). a large number of transformed calli were obtained on murashige and shoog's (ms) medium lacking plant growth regulators. frequency of transformation was about 3.5×10(-3). in most of the calli, hairy roots appeared on ms medium without plant growth regulator. when the hairy roots were cut into segments and subcultured on ms medium lacking plant growth regulators, calli were re ...198624248042
a disarmed binary vector from agrobacterium tumefaciens functions in agrobacterium rhizogenes : frequent co-transformation of two distinct t-dnas.binary ti plasmid vector systems consist of two plasmids in agrobacterium, where one plasmid contains the dna that can be transferred to plant cells and the other contains the virulence (vir) genes which are necessary for the dna transfer but are not themselves stably transferred. we have constructed two nononcogenic vectors (parc4 and parc8) based on the binary ti plasmid system of agrobacterium tumefaciens for plant transformation. each vector contains the left and right termini sequences from ...198624307418
transformation of cucumber (cucumis sativus l.) plants with agrobacterium rhizogenes.transgenic cucumber plants (cucumis sativus l., cv. 'straight eight') were regenerated from roots induced by inoculation of inverted hypocotyl sections with agrobacterium rhizogenes containing the vector parc8 in addition to the resident ri-plasmid. the dna transferred to the plant from the vector (t-dna) included a gene which encoded the enzyme neomycin phosphotransferase ii, and thus conferred on the plant cells resistance to kanamycin. the transgenic plants looked normal and were positive for ...198624240740
developmental regulation of ri tl-dna gene expression in roots, shoots and tubers of transformed potato (solanum tuberosum cv. desiree).expression of tl-dna from agrobacterium rhizogenes plasmid pri 1855 was examined in a transformed derivative of solanum tuberosum cv. desiree, d9x8a. northern blot analysis identified at least nine tl-dna coded transcripts in roots, shoots and tubers but their relative abundance differed within and between organs. this revealed a distinctive pattern of organ specified differential expression. grafting experiments showed that the abnormal shape of tubers of transformed potato was probably determi ...198624307382
transformation of cultivated tomato by a binary vector in agrobacterium rhizogenes: transgenic plants with normal phenotypes harbor binary vector t-dna, but no ri-plasmid t-dna.cultivated tomato was genetically transformed using two procedures. in the first procedure, punctured cotyledons were infected with "disarmed" agrobacterium tumefaciens strain lba4404 or with a. rhizogenes strain a4, each containing the binary vector parc8. the chimeric neomycin phosphotransferase (npt ii) gene on parc8 conferred on transformed plant cells the ability to grow on medium containing kanamycin. transformation reproducible yielded kanamycin-resistant transformants in different tomato ...198624248198
alkaloid production by hairy root cultures in atropa belladonna.hairy roots were induced by inoculation of stems of sterile plants of atropa belladonna with agrobacterium rhizogenes. the axenic culture of the hairy roots isolated from the stems proliferated 60 fold as based on the initial fresh weight after one month of culture. the presence of atropine and scopolamine in hairy roots were examined by tlc and hplc. their amounts were analyzed by glc. the results show that the amount of the two alkaloids in the axenic cultures was the same as or even higher th ...198624248236
localization of agrobacterium rhizogenes t-dna in plant chromosomes by in situ hybridization.we have used in situ hybridization to determine the sites of insertion of agrobacterium rhizogenes ri t-dna in the chromosomes of crepis capillaris (2n = 6) transformed roots. four transformed root lines were obtained by infecting crepis stem segments with a. rhizogenes. southern hybridization analysis indicated that each root line was the result of one or more independent t-dna insertion events. in two root lines, one copy of t-dna was present; the other two root lines each contained two copies ...198616453703
complementation of agrobacterium tumefaciens tumor-inducing aux mutants by genes from the t(r)-region of the ri plasmid of agrobacterium rhizogenes.in this paper we provide information indicating that the agropine-type root-inducing (ri) plasmid pri1855 of agrobacterium rhizogenes contains functional genes for auxin production (aux) in the right transferred dna (t-dna) region (t(r)-region). these genes were cloned and introduced into the t-region of the tumor-inducing (ti) plasmids of mutants of agrobacterium tumefaciens carrying an aux mutation. depending on the ri aux gene present, the oncogenicity of the ti aux-1 and/or aux-2 mutations w ...198616593762
response of various cucurbits to infection by plasmid-harboring strains of agrobacterium.tumor formation in cucurbit cultivars resulting from infection by various strains of agrobacterium tumefaciens and agrobacterium rhizogenes is environmentally affected. in all instances, tumors could be induced on excised cotyledons while inoculating attached cotyledons or stems resulted in no tumor formation. in addition, buttercup squash (cucurbita maxima duch. buttercup) was most susceptible to tumor formation, while butterbush squash (cucurbita maxima duch. butterbush) failed to form tumors ...198616665082
restriction maps and homologies of the three plasmids of agrobacterium rhizogenes strain a4.agrobacterium rhizogenes strain a4 is a virulent agropine-type strain possessing three plasmids: plasmid a (para4a, 180 kb) is not necessary for plant transformation, plasmid b (250 kb) is the root-inducing plasmid (pria4), and plasmid c (para4c) is a cointegrate of para4a and pria4. the total plasmid dna (para4) of strain a4 was cloned in the cosmid phsg262 and the library obtained was used to establish bamhi maps of the three plasmids. the plasmids a and ri have an apparently identical region ...19863018814
construction and uses of a new transposable element whose insertion is able to produce gene fusions with the neomycin-phosphotransferase-coding region of tn903.we describe the construction of a transposable element derived from the mu phage that upon insertion is able to create a gene fusion between the region of tn903 coding for neomycin phosphotransferase (npt i), which confers resistance to aminoglycosides including kanamycin (kmr), neomycin and g418, and the control elements of the gene where the insertion occurs. a chloramphenicol (cm) transacetylase gene (cat) that confers resistance to cm is present in the transposon so that transposition events ...19863015731
nucleotide sequence analysis of tl-dna of agrobacterium rhizogenes agropine type plasmid. identification of open reading frames.we have determined the nucleotide sequence of the ri tl-dna region from an agrobacterium rhizogenes agropine-type plasmid using subcloned regions from the essentially identical ri tl-dnas from strains a4 and hri. this sequenced region of 21,126 base pairs (bp) contains the complete tl-dna region of the ri plasmid as determined by analysis of tl-dna borders in the genome of infected, clonal, convolvulus arvensis plants. the left and right borders of the tl-dna are flanked by 25-bp sequences which ...19863001043
multiple mutations in the transferred regions of the agrobacterium rhizogenes root-inducing plasmids.agrobacterium rhizogenes induces root formation at the site of inoculation in plants and inserts fragments of its ri plasmid into the plant nuclear dna. the transferred region (t-dna) of the ri plasmid of the a. rhizogenes strain a4 is made of two fragments, namely tl and tr; the latter harbors a sequence homology with the tms loci (responsible for auxin synthesis) of a. tumefaciens. on daucus carota slices, single insertion mutations on the tl region of a. rhizogenes do not confer a mutant phen ...19863012616
enzymes of the beta-ketoadipate pathway are inducible in rhizobium and agrobacterium spp. and constitutive in bradyrhizobium spp.protocatechuate is a universal growth substrate for members of the family rhizobiaceae, and these bacteria utilize the aromatic compound via the beta-ketoadipate pathway. this report describes transcriptional controls exercised by different subgroups of the rhizobiaceae over five enzymes that catalyze consecutive reactions in the pathway: protocatechuate oxygenase (ec 1.13.11.3), beta-carboxy-cis,cis-muconate lactonizing enzyme (ec 5.5.1.2), gamma-carboxymuconolactone decarboxylase (ec 4.1.1.44) ...19863941043
expression vectors based on the agrobacterium rhizogenes ri plasmid transformation system.this article describes several new expression vectors that capitalize on the ability of agrobacterium rhizogenes to transfer dna from its ri plasmid to the plant nuclear genome. the intermediate vectors described include an expression cassette based on one of the three following promoters: the nopaline synthase promoter, or the cauliflower mosaic virus (camv) promoters responsible for transcription of either the 19s or 35s camv rna. the termination and polyadenylation signals are either from the ...19873111548
agrobacterium rhizogenes as a vector for transforming higher plants.agrobacterium rhizogenes is a natural vector for genetically transforming higher plants. a protocol is given for using this system to insert foreign genes into host plants. improvements currently being developed in several laboratories are also discussed.19873153165
studies on the introduction and mobility of the maize activator element in arabidopsis thaliana and daucus carota.we have co-transformed carrot (daucus carota) and arabidopsis thaliana with an agrobacterium tumefaciens non-tumorigenic t-dna carrying the maize transposable element activator (ac) and an agrobacterium rhizogenes ri t-dna. we present evidence that the ac element transposes in transformed root or root-derived callus cultures of both species. we show that fertile plants can be regenerated from transformed, root-derived callus cultures of arabidopsis, demonstrating the utility of the ri plasmid fo ...19872832144
physical map of the t-dna region of agrobacterium rhizogenes strain ncppb2659.the t-dna region of the plasmid responsible for hairy root in the agrobacterium rhizogenes strain ncppb2659 is identified and characterized by its physical map.19872827205
homology studies demonstrate colinear organization of the transferred regions of plasmids pri 1855 and pri 8196 from agrobacterium rhizogenes.agrobacterium rhizogenes, a pathogenic bacterium determining for hairy-root tumors in plants, acts by insertion of a fragment (t-dna) of its ri plasmid into the plant nuclear dna. two a. rhizogenes strains, pri 1855 and pri 8196, responsible for similar disease symptoms, differ when compared at the structural level. however, some morphogenetic loci previously identified by insertion mutagenesis in either one of the two t-dnas seem physiologically equivalent. the possibility that these morphogene ...19873615659
cytokinin production by agrobacterium and pseudomonas spp.the production of cytokinins by plant-associated bacteria was examined by radioimmunoassay. strains producing trans-zeatin were identified in the genera agrobacterium and pseudomonas. agrobacterium tumefaciens strains containing nopaline tumor-inducing plasmids, a. tumefaciens lippia isolates, and agrobacterium rhizogenes strains produced trans-zeatin in culture at 0.5 to 44 micrograms/liter. pseudomonas solanacearum and pseudomonas syringae pv. savastanoi produced trans-zeatin at levels of up t ...19873624204
a new vector derived from agrobacterium rhizogenes plasmids: a micro-ri plasmid and its use to construct a mini-ri plasmid.a new binary vector system has been constructed, based on agropine-type root-inducing plasmid (pri) left transferred-region border sequences cloned in a plasmid containing the replication origin of another a. rhizogenes plasmid (para4a). this micro-pri has been used to introduce a chimeric kanamycin resistance gene into tobacco plants, vir functions being provided by either octopine or nopaline tumor-inducing plasmids deleted of their own transferred regions. in addition, we show that cloning of ...19873623102
production of hyoscyamine by 'hairy root' cultures of datura stramonium.'hairy root' cultures of datura stramonium were established following infection of aseptic leaves with agrobacterium rhizogenes. transformation was confirmed by southern blotting using [ (32)p]-labelled fragments of the t-dna as probes. the transformed cultures grew in the absence of added phytohormones and cell mass increased 55-fold during 28 days incubation. hyoscyamine was a major component of the alkaloid fraction and accounted for at least 0.3% of the dry matter, comparable to pot-grown pl ...198717269071
agrobacterium rhizogenes t-dna genes capable of inducing hairy root phenotype.segments of the tl-dna of the agropine type ri plasmid pri 1855 encompassing single and groups of open-reading frames were cloned in the ti plasmid-derived binary vector system bin 19. leaf disc infections on nicotiana tabacum led to transformed plants, some of which showed typical hairy root phenotypes, such as the wrinkled leaf morphology, excessive and partially non geotropic root systems and the ability of leaf explants to differentiate roots in a hormone-free culture medium. particularly in ...198717193709
expression of a complete soybean leghemoglobin gene in root nodules of transgenic lotus corniculatus.the complete soybean leghemoglobin lbc(3) gene was transferred into the legume lotus corniculatus using an agrobacterium rhizogenes vector system. organ-specific expression of the soybean gene was observed in root nodules formed on regenerated transgenic plants after infection with rhizobium loti. the primary transcript was processed in the same way as in soybean nodules and the resulting mrna was translated into lbc(3) protein. quantitative determination of the lbc(3) protein in nodules of tran ...198716593870
independent and synergistic activity of rol a, b and c loci in stimulating abnormal growth in plants.the ri plasmid a4 of agrobacterium rhizogenes contains within its t-dna genetic information able to trigger root formation in infected plants. tobacco plants regenerated from transformed roots display the hairy root (hr) syndrome. we show that dna fragments containing the rol b locus alone are able to induce root formation both in tobacco and kalanchoe tissues. the rol a and the rol c loci by themselves are also able to induce root formation in tobacco but not in kalanchoe. this capacity to indu ...198716453816
segregation of genes transferred to one plant cell from two separate agrobacterium strains.agrobacterium tumefaciens and agrobacterium rhizogenes are soil bacteria which transfer dna (t-dna) to plant cells. two agrobacterium strains, each with a different t-dna, can infect plants and give rise to transformed tissue which has markers from both t-dnas. although marker genes from both t-dnas are in the tissue, definitive proof that the tissue is a cellular clone and that both t-dnas are in a single cell is necessary to demonstrate cotransformation. we have transferred two distinguishable ...198724301306
assessment of the efficiency of cotransformation of the t-dna of disarmed binary vectors derived from agrobacterium tumefaciens and the t-dna of a. rhizogenes.co-transfer of agrobacterium rhizogenes t-dna and t-dna from the a. tumefaciens binary vector pbin19 (bevan, 1984) was studied in detail using nicotiana rustica. high frequencies of co-transfer of t-dna's were observed, even when no selection pressure was exerted. increased levels of pbin19 t-dna were found in hairy root cultures with selection at higher levels of kanamycin sulphate (50-200 μg ml(-1)). several other species were also transformed by a. rhizogenes carrying pbin19 and a. rhizogenes ...198724277194
regeneration of horseradish hairy roots incited by agrobacterium rhizogenes infection.surface-sterilized leaf disks of horse-radish (armoracia lapathifolia) were immersed in a suspension of agrobacterium rhizogenes harboring the root-inducing plasmid (pri) and cultured on a solid medium. within about 10 days after inoculation, adventitious roots (hairy roots) emerged from the leaf disks. no roots emerged from the uninoculated leaf disks. the excised hairy roots grew vigorously in the dark and exhibited extensive lateral branches in the absence of phytohormones. when the hairy roo ...198724248760
ri-plasmid as a helper for introducing vector dna into alfalfa plants.genetic engineering of legumes and other important dicotyledonous plants is limited because of the difficulty of regenerating plants via cell culture. since a considerable number of crop plants can be regenerated only from root culture, the introduction of foreign genes into agrobacterium rhizogenes-induced hairy roots may expand the list of crop plants that could be genetically engineered. here we report genetic transformation of alfalfa (medicago sativa l.), a valuable forage legume, using a v ...198724301125
hairy root transformation in alfalfa (medicago sativa l.).the widely cultivated forage legume alfalfa (medicago sativa l.) was transformed with the agropine type agrobacterium rhizogenes ncppb 1855. sterile root and callus cultures were derived from tumorous hairy roots which were easily obtained independent of the plant variety or genotype. plant regeneration, via somatic embryogenesis, was achieved only when a selected alfalfa line, characterized by high regenerative capability, was utilized. genetic transformation was confirmed by the presence of ag ...198724241108
conserved regions in the t-dna of different agrobacterium rhizogenes root-inducing plasmids.the t-regions of the three so far identified types of ri plasmids-corresponding to the synthesis of three different hairy root opines, agropine, mannopine and cucumopine-have been compared in detail by southern blot cross hybridizations. two distinct zones of very strong sequence homology, approximately 4 and 3 kilobases in length respectively, have been identified in all three t-regions. the highly conserved sequences, not present in ti plasmid t-dna, may encode essential rhizogenic functions c ...198724276794
saponin production by cultures of panax ginseng transformed with agrobacterium rhizogenes.hairy root culture of ginseng (panax ginseng) was established after roots were induced on callus following infection with agrobacterium rhizogenes. the transformed cultures of ginseng could be subcultured as an axenic root culture in the absence of phytohormones, and grew with extensive lateral branches more rapidly than the ordinary cultured roots induced by hormonal control from ginseng callus. the hairy roots synthesized the same saponins, ginsenosides, as those of the native root, up to abou ...198724248930
effect of the differentiated or dedifferentiated state of tobacco pith tissue on its behaviour after inoculation with agrobacterium rhizogenes.the ability of nicotiana tabacum (cv. wisconsin 38) pith tissue to give rise to transformed roots after inoculation with agrobacterium rhizogenes (agropine type strain 1855) has been examined in relation to its state of differentiation. in young plants, all the stem tissues are able to initiate transformed roots while pith of adult plants does not react. mature pith, composed mostly of polyploid and non-dividing cells, is able to recover susceptibility when placed in vitro on a medium containing ...198824241545
t-dna length variability in mannopine hairy root: more than 50 kilobasepairs of pri t-dna can integrate in plant cells.independent carrot (daucus carota) hairy root lines were established by inoculation of discs taken from the same carrot with agrobacterium rhizogenes 8196 and a. tumefaciens c58c1(pri8196) carrying pri8196. several lines were compared with respect to t-dna length. one of them was found to have integrated sequences covering more than 50 kbp of the ri plasmid.198824241540
genetic transformation of cauliflower (brassica oleracea l. var. botrytis) by agrobacterium rhizogenes.cauliflower plantlets were inoculated with different agrobacterium rhizogenes strains. numerous hairy roots were induced on cauliflower hypocotyls by agropine-type strains. fewer roots were obtained with mannopine-type strains. in vitro cultures were established both from normal and hairy roots. plant regeneration occured spontaneously from normal and transformed roots. regenerated plants contained the same opines (if present) as root cultures. some mannopine-positive regenerants displayed a mod ...198824241539
establishment of new axenic hairy root lines by inoculation with agrobacterium rhizogenes.cultured hairy root lines resulting from infection by agrobacterium rhizogenes are known for approximately thirty plant species. we extend this range by establishing forty original dicotyledonous hairy root lines with a. rhizogenes strain a4. hairy roots have been cultured for at least 2-6 years on murashige & skoog medium. some hairy root cultures such as anagallis arvensis and antirrhinum majus spontaneously regenerated whole plants.198824241404
root induction on several solanaceae species by agrobacterium rhizogenes and the determination of root tropane alkaloid content.using agrobacterium rhizogenes, roots were induced on explants of 24 different solanaceae species and established as in vitro cultures. some of the root clones produced tropane alkaloids at levels similar to roots of the corresponding intact plants and maintained these levels over several passages.198824240425
a common organization of the t-dna genes expressed in plant hairy roots induced by different plasmids of agrobacterium rhizogenes.the recently described pathogenic plasmid from agrobacterium rhizogenes 2659 induces "hairy root" proliferation in infected plants which synthesize a new opine type, provisionally called cucumopine. the t-dna restriction site map of 2659 differs from other pri t-dnas, i.e., mannopine and agropine. however all these three different t-dnas have a similar organization as detected through hybridization. this, previously shown by our cross-hybridization studies between mannopine and agropine pri t-dn ...198824277622
common evolutionary origin of the central portions of the ri tl-dna of agrobacterium rhizogenes and the ti t-dnas of agrobacterium tumefaciens.analysis of published sequences for ri tl-dna (root-inducing left-hand transferred dna) of agrobacterium rhizogenes revealed several unsuspected structural features. first, ri tl-dna genes are redundant. using redundancy as a criterion, three regions (left, middle and right) were discerned. the left one, orfs (open reading frames) 1-7, contains no detectable redundancy. in the middle region a highly diverged gene family was detected in orfs 8, 11, 12, 13 and 14. the right region contains an appa ...198824272624
regeneration of flax plants transformed by agrobacterium rhizogenes.regeneration of flax (linum usitatissimum) following transformation by either agrobacterium tumefaciens carrying a disarmed ti-plasmid vector, or agrobacterium rhizogenes carrying an unmodified ri plasmid, was examined. hypocotyl and cotyledon explants inoculated with a. tumefaciens formed transformed callus, but did not regenerate transformed shoots either directly or via callus. however, cotyledon explants inoculated with a. rhizogenes formed transformed roots which did regenerate transformed ...198824272489
alkaloid production by transformed root cultures of catharanthus roseus.transformed roots of catharanthus roseus were obtained following infection of detached leaves with agrobacterium rhizogenes. roots would not grow in full strength gamborg's b5 medium but would grow satisfactorily if the medium was diluted to one half strength. little alkaloid appeared in the growth medium but root tissue contained a high level and wide variety of alkaloids. ajmalicine, serpentine, vindolinine and catharanthine were prominent components. vinblastine could also be detected by a co ...198824241871
hairy roots are more sensitive to auxin than normal roots.responses to auxin of lotus corniculatus root tips or protoplasts transformed by agrobacterium rhizogenes strains 15834 and 8196 were compared to those of their normal counterparts. three different types of experiments were performed, involving long-term, medium-term, or short-term responses to a synthetic auxin, 1-naphthaleneacetic acid. root tip elongation, proton excretion by root tips, and transmembrane electrical potential difference of root protoplasts were measured as a function of exogen ...198816593928
single genes from agrobacterium rhizogenes influence plant development.the combined expression of the rol a, b, and c loci of agrobacterium rhizogenes ri-plasmids establishes, in transgenic tobacco plants, a pathological state called hairy-root syndrome. however, when expressed separately they provoke distinct developmental abnormalities characteristic for each rol gene. moreover, changes in their mode of expression obtained by replacing the promoters of the rol b and c genes with the cauliflower mosaic virus 35s promoter elicit new and distinct developmental patte ...198815977331
reversion of aberrant plants transformed with agrobacterium rhizogenes is associated with the transcriptional inactivation of the t(l)-dna genes.transgenic plants harboring the left transfer dna (t(l)-dna) of the root inducing plasmid of agrobacterium rhizogenes show many developmental abnormalities. we observed frequent appearance of normal looking lateral (revertant) shoots from such aberrant plants. unlike aberrant shoots of the plant, revertant shoots exhibited a very high growth rate and set viable seeds. sexual and vegetative reproduction studies showed inheritance of the revertant phenotype. southern hybridization experiments demo ...198816665950
map location on agrobacterium root-inducing plasmids of homologies with the virulence region of tumor-inducing plasmids.southern-type hybridizations were carried out in order to identify sequence homologies with the pti vir loci, on an agropine-type plasmid (prihri) and a mannopine-type plasmid (pri8196) of agrobacterium rhizogenes. the localization of the sequences hybridizing with subcloned fragments containing vir a, b, g, c, and d from ptiach5 indicated a similar linear organization of the pti vir loci and their homologies on prihri and pri8196, though no homology was detected on both pri with a 1.1-kb intern ...19882852815
rola locus of the ri plasmid directs developmental abnormalities in transgenic tobacco plants.plants containing the left t-dna (tl) of agrobacterium rhizogenes show a variety of developmental abnormalities that include severely wrinkled leaves, loss of apical dominance, reduced geotropism of roots, reduced internode distances, and floral hyperstyly. the tl-dna also affects the morphology of tumor tissue at the site of inoculation on kalanchoe diagremontiana leaves. single mutations at four loci of the tl-dna (rola, rolb, rolc, and rold) are known to affect tumor morphology on k. diagremo ...19883166443
organization and characterization of the vircd genes from agrobacterium rhizogenes.we have precisely localized virulent (vir) genes of the hairy root-inducing plasmid pria4b on the basis of sequence similarity with the tumor-inducing plasmid ptia6nc, and shown that the overall organizations of vir genes in both plasmids are fairly analogous, although sizes and spacer lengths in some genes differ from each other. among the vir genes thus mapped, the virc and vird loci were characterized in detail. transposon insertions in vird led to loss of tumorigenicity on kalanchoe stems an ...19883185501
mini-mulac transposons with broad-host-range origins of conjugal transfer and replication designed for gene regulation studies in rhizobiaceae.novel mini-mu derivatives were constructed, carrying a truncated laczya operon fused to the terminal 117 bp of the mu s-end, for the isolation of translational lac fusions by mini-mu-mediated insertion mutagenesis. different selectable markers (chloramphenicol resistance; gentamycin resistance) were introduced to allow selection for mini-mu insertions in different replicons and bacterial strains. a mini-mulac derivative carrying the site for conjugal transfer of plasmid rp4 (orit) and the origin ...19882838383
homology mapping of t-dna regions on three agrobacterium rhizogenes ri plasmids by electron microscope heteroduplex studies.recombinant plasmids carrying segments of the agrobacterium rhizogenes t-dna regions of the three ri plasmids 1855 (tl-dna only), 8196, and 2659 were used for establishing homology maps by electron microscope examination of heteroduplexes. plasmid dna was linearized by digestion with suitable restriction endonucleases in order to generate large t-dna segments. heteroduplexes were prepared in 50% formamide and spread under standard conditions. measurements of double and single strands allowed the ...19882843937
reproduction of meloidogyne javanica on plant roots genetically transformed by agrobacterium rhizogenes.reproduction of meloidogyne javanica was compared on several agrobacterium rhizogenes-transformed root cultures under monoxenic conditions. m. javanica reproduced on all transformed roots tested; however, more females and eggs were obtained on potato and south australian early dwarf red tomato than on bindweed, tropic tomato, lima bean, or carrot. roots that grew at moderate rates into the agar and produced many secondary roots supported the highest reproduction. numbers of females produced in c ...198819290260
transport of the nematicide oxamyl in roots transformed with agrobacterium rhizogenes.infection of roots transformed with agrobacterium rhizogenes by meloidogyne incognita and heterodera schachtii second-stage juveniles was established in bicompartmental petri dishes. one compartment contained the murashige and skoog agar medium and the nematicide oxamyl, and the other compartment contained water agar. transformed roots of carrot, tomato, alfalfa, cowpea, rape, and sugarbeet were placed in the nutrient compartment and grew over the barrier that divided the petri dishes and into t ...198819290298
cell-autonomous behavior of the rolc gene of agrobacterium rhizogenes during leaf development: a visual assay for transposon excision in transgenic plants.we describe a genetic switch based on the ac transposable element of maize and the rolc gene of agrobacterium rhizogenes, a dominant gene, which has pleiotropic effects on plant growth and morphology. moreover, rolc gene expression under the control of the 35s cauliflower mosaic virus promoter decreases chlorophyll content in transgenic tobacco plants. chlorophyll is a visible cell-autonomous marker, and it is shown here that the reduction in chlorophyll content caused by the rolc gene product a ...19892562512
nucleotide sequence of the tzs gene from agrobacterium rhizogenes strain a4. 19892685753
induction and growth properties of carrot roots with different complements of agrobacterium rhizogenes t-dna.single and multiple infections of carrot discs were carried out with agrobacterium strains harbouring different segments of pri1855 tl-dna cloned in the binary vector bin 19 and with a strain carrying the tr-dna from the same ri plasmid. roots induced by the various co-inoculations were cultured and their growth patterns were followed. abundant roots could be induced by tl-dna rol genes a, b and c as a single insert (rola + b + c) and by rolb alone provided an extended segment beyond its 5' non- ...19892562759
promoters of the rola, b, and c genes of agrobacterium rhizogenesare differentially regulated in transgenic plants.chimeric genes containing the beta-glucuronidase reporter gene under the control of the rola, b, and c promoters of agrobacterium rhizogenes are expressed in a regulated manner in transgenic plants. the intergenic region separating the rolb and c genes represents a bidirectional promoter. this bidirectional promoter regulates transcription for both genes in a similar fashion in aerial organs of the plants, but in a distinct way in roots. moreover, both rolb and c promoter activities differ from ...19892535517
use of roots transformed by agrobacterium rhizogenes in rhizosphere research: applications in studies of cadmium assimilation from sewage sludges.the use of roots transformed by agrobacterium rhizogenes in models for the rhizosphere is discussed. a list of species for which transformed root cultures have been obtained is provided and the example of studies of cadmium assimilation from sewage sludges is given to illustrate how transformed root cultures can be used in physiological tests under non-sterile conditions.19892491656
alkaloid production by transformed root cultures of cinchona ledgeriana.transformed root cultures of cinchona ledgeriana have been generated by infecting shoots cultured in vitro with agrobacterium rhizogenes lba9402. these root cultures grow axenically in the absence of antibiotics or exogenous plant growth regulators in media containing gamborg b5 salts at half or full strength with 3% (w/v) sucrose as the carbon source. they show a 6- to 8-fold increase in fresh weight in 28 days. transformation has been confirmed by southern blotting using [ (32)p]-labelled frag ...198917262435
analysis of tr-dna/plant junctions in the genome of a convolvulus arvensis clone transformed by agrobacterium rhizogenes strain a4.a charon 4a phage library, containing insert dna isolated from a morning glory (convolvulus arvensis) plant genetically transformed by ri t-dna from agrobacterium rhizogenes strain a4, was used to isolate a lambda clone that contains part of the ri tl-dna and the complete tr-dna. the two ri t-dnas were recovered adjacent to each other in a tail-to-tail configuration (i.e. with the tr-dna inverted with respect to the tl-dna). comparison of nucleotide sequences from this lambda clone with the corr ...198924272719
expression and inheritance of inserted markers in binary vector carrying agrobacterium rhizogenes-transformed potato (solanum tuberosum l.).transgenic shoots were regenerated from eight diploid potato hairy root clones obtained by transformation with agrobacterium rhizogenes harboring next to its wild-type ri-plasmid a binary vector containing the neomycin phosphotransferase and the β-glucuronidase genes. the plants exhibited the typical hairy root phenotype. of the plants isolated, 58% were tetraploid and 38% were diploid. flowering and tuberization was much better in the diploid than in the tetraploid plants. transgenic plants for ...198924225832
efficient transformation of potato (solanum tuberosum l.) using a binary vector in agrobacterium rhizogenes.we transformed three potato (solanum tuberosum l.) genotypes by using a. rhizogenes or a mixture of a. rhizogenes and a. tumefaciens. inoculations of potato stem segments were performed with agrobacterium rhizogenes am8703 containing two independent plasmids: the wild-type ri-plasmid, pri1855, and the binary vector plasmid, pbi121. in mixed inoculation experiments, agrobacterium rhizogenes lba1334 (pri1855) and agrobacterium tumefaciens am8706 containing the disarmed ti-plasmid (pal4404) and the ...198924225690
efficient transformation with regeneration of the tropical pasture legumestylosanthes humilis usingagrobacterium rhizogenes and a ti plasmid-binary vector system.agrobacterium rhizogenes carrying the binary ti plasmid vector pga492 was used to transform leaf and stem explants of the tropical pasture legumestylosanthes humilis. conditions which yielded kanamycin resistant roots at a frequency of up to 86% and subsequent plant regeneration at a frequency of 23% were defined. transgenic plants were fertile and either grew normally or had stunted growth but otherwise showed only minor morphological abnormalities. transgenic plants with normal phenotypes were ...198924233271
production of nematocidal compounds by hairy root cultures of tagetes patula l.marigold (tagetes patula l.) hairy roots induced by infection with agrobacterium rhizogenes produced α-terthienyl when grown in darkness, and an n-hexane extract of the roots showed nematocidal activity. depending on the hairy root line used, the level of α-terthienyl varied from 15 to 1268 μg per g dry weight, a level that corresponded to 0.15 to 12.7-fold that in intact roots. analysis by hplc indicated that the nematocidal activity was due predominantly to α-terthienyl. however, it is suggest ...199024227063
lobeline production by hairy root culture of lobelia inflata l.hairy roots were obtained following inoculation of the stems of lobelia inflata l. with agrobacterium rhizogenes strain atcc 15834. these hairy roots contained agropine and mannopine. in addition, lobeline was detected by hplc and confirmed by mass spectrometry. various media were tested for the growth of hairy roots as well as for the content of lobeline in hairy roots. the growth rate of hairy roots cultured in nitsch and nitsch's medium was approximately one third of those cultured in other m ...199024226939
enzymes of n-methylputrescine biosynthesis in relation to hyoscyamine formation in transformed root cultures of datura stramonium and atropa belladonna.the activities of enzymes related to the biosynthesis of n-methylputrescine, a precursor of the alkaloid hyoscyamine, have been measured in root cultures of datura stramonium l. and atropa belladonna l. transformed with agrobacterium rhizogenes. ornithine δ-nmethyltransferase and δ-n-methylornithine decafboxylase were undetectable, indicating that δ-n-methylornithine is an unlikely intermediate in the formation of n-methylputrescine. the activity of putrescine-n-methyltransferase (ec 2.1.1.53) w ...199024197009
recovery of morphologically normal transgenic tobacco from hairy roots co-transformed with agrobacterium rhizogenes and a binary vector plasmid.co-transformation of tobacco (nicotiana tabacum) leaf explants with agrobacterium rhizogenes harbouring pri1855 and the binary vector pbin19 was achieved at a frequency of 67%. the kanamycin resistant hairy roots were cultured via a callusing phase to regenerate plants which were partially fertile when outcrossed with wild-type pollen. phenotypic and molecular analysis of the f1 progeny demonstrated the efficient segregation of the hairy root marker from the kanamycin resistance marker, enabling ...199024226437
factors regulating tropane-alkaloid production in a transformed root culture of a datura candida × d. aurea hybrid.using in combination an analysis of (i) the levels of enzyme activities present, (ii) the pool sizes of metabolic intermediates and end products and (iii) the effects of feeding metabolic intermediates, the limitations ℴ flux into tropane alkaloids in a datura root culture have been examined. this culture, produced by transforming a datura candida × d. aurea hybrid with agrobacterium rhizogenes, is found to be highly competent in the biosynthesis of both hyoscyamine and scopolamine as well as a ...199024196820
accumulation of rare phenylpropanoids in agrobacterium rhizogenes transformed root cultures of coreopsis tinctoria. 199017221456
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