SEARCH · PubMed Health

Results for “Raphanus”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

PubMedDate not supplied

Plant mitochondrial DNA evolves rapidly in structure, but slowly in sequence.

We examined the tempo and mode of mitochondrial DNA (mtDNA) evolution in six species of crucifers from two genera, Brassica and Raphanus. The six mtDNAs have undergone numerous internal rearrangements and therefore differ dramatically with respect to the sizes of their subgenomic circular chromosomes. Between 3 and 14 inversions must be postulated to account for the structural differences found between any two species. In contrast, these mtDNAs are extremely similar in primary sequence, differing at only 1-8 out of every 1000 bp. The point mutation rate in these plant mtDNAs is roughly 4 times slower than in land plant chloroplast DNA (cpDNA) and 100 times slower than in animal mtDNA. Conversely, the rate of rearrangements is extraordinarily faster in plant mtDNA than in cpDNA and animal mtDNA.

Animal Population Groups↗

PubMed1988

A fern spore storage protein is genetically similar to the 1.7 S seed storage protein of Brassica napus.

The ostrich fern, Matteuccia struthiopteris L., contains two globulin spore storage proteins of 2.2 S and 11.3 S, with physical characteristics similar to those of seed storage proteins of Brassica napus (rapeseed) and Raphanus sativus (radish). By the use of a cloned cDNA that encodes the 1.7 S B. napus storage protein (napin), gene sequences that hybridized with napin were detected in fern nuclear DNA, and a 900-nucleotide homologous mRNA was detected in developing spores. In vitro translation of this fern mRNA produced a 22-kD polypeptide comparable in size to the 21-kD precursor polypeptide identified in Brassica. No hybridizations were observed between the Brassica 12 S clone and either fern DNA or developing spore mRNA.

Blotting, Southern↗

PubMed1991

Aspects related to mevalonate biosynthesis in plants.

We purified and characterized a membrane-associated enzyme system from radish (Raphanus sativus L.) that is capable of converting acetyl-CoA into 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA). The enzyme system apparently comprises acetoacetyl-CoA thiolase (EC 2.3.1.9) and HMG-CoA synthase (EC 4.1.3.5). Its activity in vitro can be strongly stimulated by FeII. When ferrous ions are applied chelated with ethylenediaminetetraacetate, citrate or adenosine 5-triphosphate (ATP), the stimulation is further increased. Stimulation is due to a higher catalytic efficiency as indicated by an increase in Vmax, whereas the affinity of the enzyme towards acetyl-CoA remains constant (Km = 6 micro M). A considerable portion of HMG-CoA lyase activity is associated with the same membranes. HMG-CoA lyase (EC 4.1.3.4) is also solubilized and partially co-purified. Its activity requires comparatively high concentrations of Mg2+. The conversion of HMG-CoA to mevalonic acid is catalyzed by HMG-CoA reductase (EC 1.1.1.34) that is associated with the same membranes. By cDNA encoding the Arabidopsis HMG-CoA reductase, we isolated a corresponding gene from a cDNA library newly established from etiolated radish seedlings. This full-length cDNA, referred to as lambda cRS3, encodes a polypeptide 583 amino acids with a molecular mass of about 63 kDa. The hydropathy profile suggests the presence of two hydrophobic membrane-spanning domains within the N-terminal 165 amino acids. The carboxy-terminal part, where the catalytic site resides, is highly conserved in all eukaryotic HMG-CoA reductase genes sequenced so far.

Acetyl Coenzyme A↗

PubMed1998

Phylogenetic position of the Hexactinellida within the phylum Porifera based on the amino acid sequence of the protein kinase C from Rhabdocalyptus dawsoni.

Recent analyses of genes encoding proteins typical for multicellularity, especially adhesion molecules and receptors, favor the conclusion that all metazoan phyla, including the phylum Porifera (sponges), are of monophyletic origin. However, none of these data includes cDNA encoding a protein from the sponge class Hexactinellida. We have now isolated and characterized the cDNA encoding a protein kinase C, belonging to the C subfamily (cPKC), from the hexactinellid sponge Rhabdocalyptus dawsoni. The two conserved regions, the regulatory part with the pseudosubstrate site, the two zinc fingers, and the C2 domain, as well as the catalytic domain were used for phylogenetic analyses. Sequence alignment and construction of a phylogenetic tree from the catalytic domains revealed that the yeast Saccharomyces cerevisiae and the protozoan Trypanosoma brucei are at the base of the tree, while the hexactinellid R. dawsoni branches off first among the metazoan sequences; the other two classes of the Porifera, the Calcarea (the sequence from Sycon raphanus was used) and the Demospongiae (sequences from Geodia cydonium and Suberites domuncula were used), branch off later. The statistically robust tree also shows that the two cPKC sequences from the higher invertebrates Drosophila melanogaster and Lytechinus pictus are most closely related to the calcareous sponge. This finding was also confirmed by comparing the regulatory part of the kinase gene. We suggest, that (i) within the phylum Porifera, the class Hexactinellida diverged first from a common ancestor to the Calcarea and the Demospongiae, which both appeared later, and (ii) the higher invertebrates are more closely related to the calcareous sponges.

Amino Acid Sequence↗

PubMed2006

Plastid genome characterisation in Brassica and Brassicaceae using a new set of nine SSRs.

We report a new set of nine primer pairs specifically developed for amplification of Brassica plastid SSR markers. The wide utility of these markers is demonstrated for haplotype identification and detection of polymorphism in B. napus, B. nigra, B. oleracea, B. rapa and in related genera Arabidopsis, Camelina, Raphanus and Sinapis. Eleven gene regions (ndhB-rps7 spacer, rbcL-accD spacer, rpl16 intron, rps16 intron, atpB-rbcL spacer, trnE-trnT spacer, trnL intron, trnL-trnF spacer, trnM-atpE spacer, trnR-rpoC2 spacer, ycf3-psaA spacer) were sequenced from a range of Brassica and related genera for SSR detection and primer design. Other sequences were obtained from GenBank/EMBL. Eight out of nine selected SSR loci showed polymorphism when amplified using the new primers and a combined analysis detected variation within and between Brassica species, with the number of alleles detected per locus ranging from 5 (loci MF-6, MF-1) to 11 (locus MF-7). The combined SSR data were used in a neighbour-joining analysis (SMM, D (DM) distances) to group the samples based on the presence and absence of alleles. The analysis was generally able to separate plastid types into taxon-specific groups. Multi-allelic haplotypes were plotted onto the neighbour joining tree. A total number of 28 haplotypes were detected and these differentiated 22 of the 41 accessions screened from all other accessions. None of these haplotypes was shared by more than one species and some were not characteristic of their predicted type. We interpret our results with respect to taxon differentiation, hybridisation and introgression patterns relating to the 'Triangle of U'.

Base Sequence↗

PubMed1999

Biodegradation and ecotoxicity of HFCs and HCFCs.

Hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) are used or developed as substitutes for fully halogenated chlorofluorocarbons. Based on the results of closed-bottle tests, the biodegradation of HFC-32, HCFC-123, HCFC-124, HFC-125, HFC-134a, HCFC-141b, HCFC-225ca, and HCFC-225cb was less than 60% after 28 days and therefore these compounds are considered not readily biodegradable. Standard acute toxicity tests with HCFC-123, HCFC-141b, and HCFC-225ca using algae, water fleas, and fish revealed EC50 values in the range of 17-126 mg/L. EC50 values of HFC-134a ranged between 450-980 mg/L. Fish studies with HCFC-141b and HCFC-225ca revealed bioaccumulation factors of <3 and 15-64, respectively. A study with plants revealed no effect of HCFC-141b on seed germination and growth of wheat (Triticum aestivum), radish (Raphanus sativus), and cress (Lepidium sativum). In conclusion, HFCs and HCFCs are not very toxic to aquatic organisms and terrestrial plants. No evidence for any aerobic biodegradation for most of the HFCs and HCFCs was found.

Animals↗

PubMed2001

Specificity of the accumulation of mRNAs and proteins of the plasma membrane and tonoplast aquaporins in radish organs.

Plant aquaporins occur in multiple isoforms and are distributed in both plasma membrane and tonoplast. We cloned cDNAs for plasma-membrane aquaporins (PAQ1, 1b, 1c, 2, 2b, and 2c) of radish (Raphanus sativus L.). The amino acid sequences of the PAQs showed on average 63% sequence identity. Their sequences were 23% identical to those of tonoplast aquaporins (gamma- and delta-VM23). A comprehensive investigation of the aquaporin mRNAs, including VM23, in seedlings, plants, flowers and seeds of radish showed a marked accumulation of all the mRNAs in hypocotyls and growing taproots. In other organs, the mRNA level of each isoform varied according to the organ. In petals, stamens, pistils and sepals of flowers, the levels of PAQ1, 1b, 1c and gamma-VM23 mRNAs were high, and mRNAs of all aquaporins except for delta-VM23 were detected at high levels in pericarps. The protein levels of aquaporins on the basis of the membrane protein were determined by immunoblotting. Proteins PAQ1 and VM23 were detected in every organ except for the mature petiole. The PAQ2 protein level was especially high in green cotyledons and leaves, but was extremely low in seedling cotyledons and hypocotyls. Proteins PAQ1, PAQ2 and VM23 were highly accumulated in growing pericarps, but not in the immature seeds. These results indicate that the gene expression of the aquaporin isoforms was individually regulated in an organ- and tissue-specific manner, and that the amounts of aquaporin protein, especially PAQ2, are regulated in certain tissues at the translational level and by the rate of protein turnover.

Amino Acid Sequence↗

PubMed1998

Nectar-carbohydrate production and composition vary in relation to nectary anatomy and location within individual flowers of several species of Brassicaceae.

Nectar-carbohydrate production and composition were investigated by high-performance liquid chromatography and enzymology in nine species from five tribes of the Brassicaceae. In six species (Arabidopsis thaliana (L.) Heynh., Brassica napus L., B. rapa L., Lobularia maritima (L.) Desv., Raphanus sativus L., Sinapis arvensis L.) that produced nectar from both lateral nectaries (associated with the short stamens) and median nectaries (outside the long stamens), on average 95% of the total nectar carbohydrate was collected from the lateral ones. Nectar from these glands possessed a higher glucose/fructose ratio (usually 1.0-1.2) than that from the median nectaries (0.2-0.9) within the same flower. Comparatively little sucrose was detected in any nectar samples except from Matthiola bicornus (Sibth. et Sm.) DC., which possessed lateral nectaries only and produced a sucrose-dominant exudate. The anatomy of the nectarial tissue in nectar-secreting flowers of six species, Hesperis matronalis L., L. maritima, M. bicornus, R. sativus, S. arvensis, and Sisymbrium loeselii L., was studied by light and scanning-electron microscopy. Phloem alone supplied the nectaries. However, in accordance with their overall nectar-carbohydrate production, the lateral glands received relatively rich quantities of phloem that penetrated far into the glandular tissue, whereas median glands were supplied with phloem that often barely innervated them. All nectarial tissue possessed modified stomata (with the exception of the median glands of S. loeselii, which did not produce nectar); further evidence was gathered to indicate that these structures do not regulate nectar flow by guard-cell movements. The numbers of modified stomata per gland showed no relation to nectar-carbohydrate production. Taken together, the data on nectar biochemistry and nectary anatomy indicate the existence of two distinct nectary types in those Brassicacean species that possess both lateral and median nectaries, regardless of whether nectarial tissue is united around the entire receptacle or not. It is proposed that the term "nectarium" be used to represent collectively the multiple nectaries that can be found in individual flowers.

Brassica↗

PubMed1998

Evidence that the role of plant defensins in radish defense responses is independent of salicylic acid.

Radish leaves contain two homologous 5-kDa plant defensins which accumulate systemically upon infection by fungal pathogens (F.R.G. Terras et al., 1995, Plant Cell 7: 573-588). Here we report on the molecular cloning of the cDNAs encoding the two pathogen-inducible plant defensin isoforms from radish (Raphanus sativus L.) leaves. Tissue-print and whole-leaf electroblot immunostaining showed that the plant defensin peptides not only accumulate at high levels at or immediately around the infection sites in leaves inoculated with Alternaria brassicicola, but also accumulate in healthy tissue further away from the infection sites and in non-infected leaves from injected plants. Gel blot analysis of RNA confirmed that expression of plant defensin genes is systemically triggered upon fungal infection whereas radish PR-1 gene expression is only activated locally. In contrast to the radish PR-1 gene(s), expression of the radish plant defensin genes was not induced by external application of salicylic acid. Activation of the plant defensin genes, but not that of PR-1 genes, occurred upon treatment with methyl jasmonate, ethylene and paraquat.

Alternaria↗

PubMed2002

Hydroponically cultivated radish fed L-galactono-1,4-lactone exhibit increased tolerance to ozone.

Leaf L-ascorbate content of an ozone (O3)-sensitive radish genotype (Raphanus sativus L. cv. Cherry Belle) was increased 2-fold by feeding hydroponically cultivated plants L-galactono- 1,4-lactone (GalL). Plants were grown in controlled-environment chambers ventilated with charcoal/Purafil-filtered air, and administered one of two O3 fumigation regimes: chronic exposure (75 nmol O3 mol(-1) for 7 h day(-1) for 21 days) and acute exposure (180 nmol O3 mol(-1) for 9 h). Chronic O3 exposure decreased root growth by 11% in plants maintained in pure nutrient solution (-GalL), but resulted in no change in root growth in GalL-fed plants (+GalL). Similarly, GalL-feeding counteracted the negative effects of O3 on CO2 assimilation rate observed in control plants (-GalL). Under acute O3 exposure, GalL-fed plants showed none of the visible symptoms of injury, which were extensive in plants not fed GalL. Leaf CO2 assimilation rate was decreased by acute 03 exposure in both GalL treatments, but the extent of the decline was less marked in GalL-fed plants. No significant changes in stomatal conductance resulted from GalL treatment, so O3 Uptake into leaves was equivalent in + GalL and -GalL plants. Feeding GalL, on the other hand, enhanced the level of ascorbate, and resulted in the maintenance of the redox state of ascorbate under acute O3 fumigation, in both the leaf apoplast and symplast. The effect of GalL treatment on ascorbate pools was consistent with the reduction in O3 damage observed in GalL-fed plants. Attempts to model O3 interception by the ascorbate pool in the leaf apoplast suggested a greater capacity for O3 detoxification in GalL-fed plants, which corresponded with the increase in O3 tolerance observed. However, modelled data for GalL-fed plants suggested that additional constituents of the leaf apoplast may play an important role in the attenuation of environmentally-relevant O3 fluxes.

Air Pollutants↗

PubMed2001

Evidence for orthologous S-locus-related I genes in several genera of Brassicaceae.

In the Brassica genus, self-incompatibility (SI) is considered to be controlled by the combined action of several highly polymorphic genes located at the S-locus. These genes, including the S-Locus Gene (SLG), and the S-Receptor Kinase (SRK) are all members of the complex multigenic S-family. The S-Locus Related I gene (SLR1) is a member of the S-family, but is not involved in SI control since it is not linked to the S-locus and is essentially monomorphic. Here we confirm or demonstrate the occurrence of SLR1 as highly diverged but not very polymorphic genes in several genera of the Brassicaceae family (Arahidopsis, Brassica, Hirschfeldia, Raphanus, Sinapis). They show similar expression patterns with respect to location (stigmatic papillae), developmental stage (before and during anthesis) and transcript size (1.6 kb). In addition, they are assumed to be involved in the same biological function (late pollen adhesion). These features suggest that the pollen adhesion function might have evolved towards self-pollen recognition through duplication of SLR1 and recruitment of a protein kinase gene.

Arabidopsis↗

PubMed1998

Involvement of cucumber mosaic cucumovirus RNA2 and RNA3 in viral systemic spread in radish plant.

The genetics of cucumber mosaic cucumovirus (CMV) and the pathogenicity of the virus for Raphanus sativus were analyzed using pseudorecombinants constructed from the infectious transcripts of two naturally occurring strains of cucumber mosaic cucumovirus (CMV-D8 and CMV-Y). CMV-D8, but not CMV-Y, could cause systemic infection of the plant. Viral accumulation and systemic movement in the plants was examined using immuno-tissue blot analysis, dot blot and Northern blot hybridization. Virus was equally distributed and CMV RNAs accumulated to similar levels in the inoculated cotyledons of radish irrespective of the pseudorecombinant, suggesting that there are no apparent differences in the ability of infection and viral accumulation between CMV-D8 and CMV-Y. We found, however, that both RNAs 2 and 3 of CMV-D8 are involved in determining the efficiency for the systemic infection of R. sativus. Co-operated interactions between genetic information of RNAs 2 and 3 would control the efficient translocation of virus from the inoculated leaves to the uninoculated upper leaves of radish plant.

Blotting, Northern↗

PubMed1990

Hydrogen peroxide formation and iron ion oxidoreduction linked to NADH oxidation in radish plasmalemma vesicles.

Previously, we showed the presence in radish (Raphanus sativus L.) plasmalemma vesicles of an NAD(P)H oxidase, active at pH 4.5-5.0, which elicits the formation of anion superoxide (Vianello and Macrí (1989) Biochim. Biophys. Acta 980, 202-208). In this work, we studied the role of hydrogen peroxide and iron ions upon this oxidase activity. NADH oxidation was stimulated by ferrous ions and, to a lesser extent, by ferric ions. Salicylate and benzoate, two known hydroxyl radical scavengers, inhibited both basal and iron-stimulated NADH oxidase activity. The iron chelators EDTA (ethylenediaminetetraacetic acid) and DFA (deferoxamine melysate) at high concentrations (2 mM) inhibited the NADH oxidation, whereas they were ineffective at lower concentrations (80 microM); the subsequent addition of ferrous ions caused a rapid and limited increase of oxygen consumption which later ceased. Hydrogen peroxide was not detected during NADH oxidation but, in the presence of salicylate, its formation was found in significant amounts. NADH oxidase activity was also associated to a Fe2+ oxidation which was only partially inhibited by salicylate. Ferrous ion oxidation was partially inhibited by catalase and prevented by superoxide dismutase, while ferric ion reduction was abolished by catalase and unaffected by superoxide dismutase. These results show that during NADH oxidation iron ions undergo oxidoreduction and that hydrogen peroxide is produced and rapidly consumed. As previously suggested, this oxidation appears linked to the univalent oxidoreduction of iron ions by a reduced flavoprotein of radish plasmalemma which is then converted to a radical form. The latter, reacting with oxygen generates the superoxide anion which dismutases to H2O2. Hydrogen peroxide, through a Fenton's reaction, may react with Fe2+ to produce hydroxyl radicals, or with Fe3+ to generate the superoxide anion.

Cell Membrane↗

PubMed1979

Preparation and characterization, using high-performance liquid chromatography, of an enzyme forming glucosides of cytokinins.

Cytokinins can occur naturally as glycosides with beta-D-glucose as the sugar substituent. From radish (Raphanus sativus) cotyledons, an enzyme has been partly purified which synthesizes the 7-glucopyranoside of zeatin [6-(4-hydroxy-3-methylbut-trans-2-enylamino)purine], a compound known to occur in this species. High-performance reverse-phase liquid chromatography was uniquely useful as the analytical procedure for quantitative study of the minute amounts of enzyme available. The enzyme uses UDPglucose as the source of the sugar residue. A large number of derivatives of purine are glucosylated, but adenine derivatives with an alkyl side chain at least three carbon atoms in length at position N6 are preferentially glucosylated. This corresponds to the structural features required for high cytokinin activity. The 7-glucoside of zeatin is known to be very weakly active in cytokinin bioassays. Hence, this enzyme, and others catalyzing the same reaction, have a role in the regulation of cytokinin activity.

Cytokinins↗

PubMed1989

Low-resolution epitope characterisation in a family of seed apolipoproteins using polyclonal antibodies.

Polyclonal antibodies raised against a range of seed apolipoproteins from the family Cruciferae have been used for the first time for low resolution epitope characterisation. Antibodies were raised against the major seed apolipoproteins of Brassica napus, Sinapis alba and Raphanus sativum. In each case, the antibodies recognized, in addition to the 19-20 kDa apolipoprotein to which they were raised, similar 19-20 kDa apolipoproteins from a wide range of species in the family Cruciferae, but not in other plant families. Homologous or heterologous two-sites (sandwich) assays were performed with the format [antibody A - test apolipoprotein - antibody B - 2 degrees antibody]. The results showed a drastically reduced antibody B binding by apolipoproteins preincubated with an antibody A. This indicated the presence of a single major epitope on many of the apolipoproteins. The antigenicity of native and denatured apolipoproteins was similar, although the antigenicity of the former was much more readily destroyed by proteinase attack. It is concluded that there are relatively few major epitopes present on the Cruciferae apolipoproteins and it is suggested that these epitopes are localized on the small hydrophilic surface-exposed C- and N-terminal domains of the apolipoproteins.

Antibodies↗

PubMed1970

Uber die quantitative Bestimmung von Sterinderivaten in pflanzen und die intrazelluläre Verteilung der Steringlycoside in Blättern.

The contents of sterol derivatives (sterols + esters, glycosides and acylated glycosides) have been determined using thin layer chromatography in leaves and bulky and organs from carrots (Daucus carota L.) potato (Solanum tuberosum L.), onion (Allium cepa L.) two varieties of radish (Raphanus sativus L.) and Gentiana purpurea L. plants. Ether-soluble lipids of leaves contain 2.8-5.2%, those of storage tissue 3.1-8.9% sterol derivatives. The fractionation of lettuce (Lactuca sativa L., Burpee's Ruby Red) leaf homogenates indicates steryl glycosides to be accumulated in a microsomal fraction.

Journal Article↗

PubMed1991

rDNA intergenic region from Arabidopsis thaliana. Structural analysis, intraspecific variation and functional implications.

The ribosomal gene intergenic region from Arabidopsis thaliana contains four clusters of mutually unrelated repeated sequences. By comparison with the respective regions in two other Brassicaceae, Raphanus and Sinapis, the putative promoter sequence for RNA polymerase I was located. The homologies suggest that the RNA polymerase I promoter in Brassicaceae ranges further upstream than in animals. Upstream duplications of at least a part of the promoter region were found to be located between individual blocks of the largest internal repeat family ("A" repeats), which is made up of multiple repeats of two closely related sequences 21 or 20 bp in length. Overall structural similarities of the A. thaliana rDNA intergenic region with those from wheat and from Xenopus laevis are discussed. We also present data on the range of intraspecific length heterogeneities found in the central EcoRI fragment of the intergenic region and on the frequencies with which specific length variants occur in the genome. To determine the nature of the length heterogeneities, we sequenced the central EcoRI fragments from four independently isolated genomic clones. Three levels of rearrangements were detected. Length variation can be caused by duplication of a whole A repeat block, or, most frequently, by insertion and/or deletion of one or a few A repeat units. Surprisingly, single base mutations are extremely rare, which hints at some mechanism of homogenization which might be acting on the intergenic region. A possible function of the described sequences in transcriptional regulation is discussed and will be the aim of further investigations.

Animals↗

PubMed1996

Carbohydrate moieties of three radish peroxidases.

The carbohydrate moieties of two anionic peroxidases, termed A1 and A2, and one cationic peroxidase, named C3, from Korean radish (Raphanus sativus) were studied. For profiling of N-glycans, each peroxidase was treated with peptidyl N-glycosidase F and hydrazine. These peroxidases were more susceptible to hydrazine than to peptidyl N-glycosidase F. When these three peroxidases were subjected to trifluoroacetic acid treatment, mannose, fucose and N-acetylglucosamine were released. Two major N-glycans of peroxidase C3 were isolated and treated with several glycohydrolases. Analysis of digested products of the two major N-glycans on polyacrylamide gel suggested that core-fucosylated trimannosylchitobiose may contain a different linkage from the typical alpha-1,6 of native N-linked oligosaccharide.

Acetylglucosamine↗