scenario ; Brassica napus ; MALAYSIAN

We have previously observed that a sequence in coat protein (CP) ORF of Turnip yellow mosaic virus (TYMV) is required for efficient replication of the virus. The sequence was predicted to take a stem-loop structure, thus termed SL2. While examining various SL2 mutants, we observed that all the modifications resulting in extension of translation beyond the CP ORF significantly suppressed subgenomic RNA accumulation. The genomic RNA level, in contrast, was not affected. Introduction of an in-frame stop codon in the CP ORF of these constructs restored the level of subgenomic RNA. Overall, the results suggest that the read-through makes the subgenomic RNA unstable.
Animals ; Brassica napus ; Codon, Terminator ; Ecthyma, Contagious ; RNA ; Tymovirus ; Viruses

Native turnip yellow mosaic virus (TYMV) is relatively unreactive to maleimide agents, indicating few reactive thiol groups on TYMV. In the present study, we aimed to construct TYMV mutants that have reactive cysteine residues on the surface. To this end, we prepared a library of TYMV mutants where the Thr residue at the C-terminus of coat protein (CP) was replaced by a random sequence of six amino acids that included one cysteine. This library was introduced into Nicotiana benthamiana by agroinfiltration. The CP sequence of the TYMV RNA isolated from inoculated leaves was amplified by reverse transcription-PCR and then used to construct a second library. This process was repeated one more time, and the CP sequences of the TYMV RNA in the inoculated leaves were analyzed. Based on the analysis of over 11,000 CP sequences, the Cys mutants representing most abundant TYMV RNAs were constructed. Analysis of the mutants showed that four Cys mutants were nearly comparable to wildtype with respect to CP and viral RNA levels in N. benthamiana. All these mutants were highly reactive to fluoresceine-5-maleimide. This demonstrates that TYMV can be modified to have additional functional groups on the surface that would be useful for drug delivery.
Amino Acids ; Brassica napus* ; Cysteine ; RNA ; RNA, Viral ; Tobacco ; Tymovirus*

It was previously observed that recombinant flock house virus (FHV) RNA1 was efficiently packaged into turnip yellow mosaic virus (TYMV), provided that the TYMV coat protein (CP) sequence was present at the 3′-end. FHV RNA encapsidated by TYMV CPs also had a four-nucleotide extension at the 5′-end. Since even a short extension at the 5′- and 3′-ends of FHV RNA1 inhibits replication, we examined whether the recombinant FHV RNA is indeed capable of replication. To this end, we introduced constructs expressing recombinant FHV RNAs into the plant Nicotiana benthamiana. Northern blot analysis of inoculated leaves suggested abundant production of recombinant FHV RNA1 and its subgenomic RNA. This demonstrated that recombinant FHV RNA with terminal extensions at both ends was competent for replication. We also showed that the recombinant FHV RNA can express the reporter gene encoding enhanced green fluorescent protein.
Blotting, Northern ; Brassica napus* ; Capsid Proteins* ; Genes, Reporter ; Plants ; RNA* ; Tobacco* ; Tymovirus*

Turnip yellow mosaic virus (TYMV) is a non-enveloped icosahedral virus that has a single 6.3 kb positive-strand RNA as a genome. Previously, it was observed that the recombinant construct TY-eGFP2, where an eGFP gene was inserted at the position downstream of the coat protein (CP) ORF of TYMV genome, barely replicated. The inhibition of replication was relieved by insertion of an additional copy of the 3' quarter of the CP ORF after the foreign sequence. In this study, we have examined if the 3' quarter of the CP ORF contains any replication elements. M-fold analysis predicted three stem-loop structures in this region. Analysis of the TY-eGFP2 constructs containing one or two of these stem-loop structures indicates that the secondary structure predicted in the region between nt-6139 and nt-6181, termed SL2, is essential for TYMV replication. The critical role of SL2 was confirmed by the observation that deletion of the 3' quarter of the CP ORF from the wild-type TYMV genome nearly abolished replication and that insertion of SL2 into the deletion mutant restored the replication. Mutations disrupting the stem of SL2 greatly reduced viral RNA replication, indicating that the secondary structure is essential for the enhancing activity.
Animals ; Brassica napus ; Coat Protein Complex I ; Ecthyma, Contagious ; Genome ; RNA ; RNA, Viral ; Tymovirus ; Viruses

Liver fibrosis is a chronic liver disease and lots of people in Korea are suffered. There are many efforts to find candidates to suppress liver fibrogenesis and several chemical-induced model or bile duct ligation model have been used to research and develop hepatic fibrogenic suppressor. From the previous study about functional effects of turnip which cultivated in Kangha Island, we got the feasibility which turnip might be able to inhibit heptatic fibrogenesis. TAA is a representative hepatic fibrosis inducer, repeated 7-weeks i.p. injection of it results in hepatic fibrosis. We compared the level of hepatic fibrosis in TAA-turnip group, TAA group, and vehicle control group. Nodules-formed by TAA were observed; they were rarely shown in vehicle control group, observed in most area in TAA group, but only shown in periportal regions in TAA-turnip group. These results were confirmed through Masson's trichrom stain; fibrous structures increased in TAA group (fibrosis score: 4) but significantly decreased in TAA-turnip group (fibrosis score: 2-3). In conclusion, we got the result that turnip water extract has a potency to protect TAA-induced hepatic fibrogenesis but it is necessary further study to find its mechanism.
Bile Ducts ; Brassica napus ; Fibrosis ; Korea ; Ligation ; Liver ; Liver Cirrhosis ; Liver Diseases ; Water

Turnip yellow mosaic virus (TYMV) is a spherical plant virus that has a single 6.3 kb positive strand RNA genome. Information for TYMV replication is limited, except that the 3'-terminal sequence and 5'-untranslated region are required for genome replication. When a foreign sequence was inserted at the position upstream of the coat protein (CP) open reading frame (ORF), replication of the recombinant TYMV was comparable to wild type, as long as an RNAi suppressor was provided. In contrast, when the foreign sequence was inserted between the CP ORF and the 3'-terminal tRNA-like structure, replication of the recombinant virus was not detected. This result suggests that the CP ORF contains an essential replication element which should be appropriately spaced with respect to the 3'-end. Analysis of TYMV constructs containing a part or a full additional CP ORF indicates that the 3' quarter of the CP ORF is required for TYMV replication.
Animals ; Brassica napus ; Ecthyma, Contagious ; Genome ; Open Reading Frames ; Plant Viruses ; RNA ; Tymovirus ; Viruses

Turnip yellow mosaic virus (TYMV) is a non-enveloped icosahedral virus composed of 20 kDa single coat proteins. In this study, we modified the TYMV coat protein (CP) ORF by inserting an oligonucleotide linker corresponding to T7, HSV, Tat, (Arg)9, or (RxR)4 peptide at the 5'-end of the CP ORF and examined its effect on replication, RNA packaging, and virion assembly. The results showed that the constructs containing (Arg)9 and (RxR)4 sequences were barely capable of replication. The TYMV constructs containing T7 and Tat peptide produced virions that co-migrated with wild-type virions. However, the insertion of T7 and Tat sequences impaired genomic RNA (gRNA) accumulation and packaging, respectively. When only the CP gene was expressed, CPs with (Arg)9 or (RxR)4 successfully produced virus-like particles whose mobility was comparable to that of wild type. In the case of CP having a HSV tag, the virion band was not detected, although a sufficient amount of CP was produced. This indicates that CP with the HSV tag failed to assemble into virions. Overall, the results suggest that TYMV replication, RNA packaging and virion assembly are strongly influenced by the insertion sequence.
Animals ; Brassica napus* ; Capsid Proteins ; Ecthyma, Contagious ; Product Packaging* ; RNA* ; Tymovirus* ; Virion*

BACKGROUND: Rapeseed-mustard is the second most important source of edible oil in India. Several species of Brassica are grown in different parts of country for its oilseeds. OBJECTIVE: The objective was to investigate allergenicity to antigenic extracts of pollen of 4 species of Brassica. METHODS: Brassica campestris, Brassica juncea, Brassica nigra, and Brassica napus were selected for the detailed investigation. Pollen samples from each of the four species were collected from the polliniferous materials. The antigenic and allergenic profiles of these extracts were evaluated by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Skin prick test, enzyme linked immuno sorbent assay and Western blot on atopic individuals. RESULTS: Out of the 159 atopic subjects tested, 21.38% were positive to at least one or other species of Brassica pollen, with highest skin positivity (13.20%) to B. campestris extract. Raised IgE with significant linear correlation with intensity of skin reactions was obtained. Protein fractions of 20, 25, 32, 37, 56, and 90 kDa were recognized by B. campestris and B. juncea whereas 56, 76, 87, and 90 kDa were recognized by B. nigra and B. napus as major IgE binding protein fractions. The patients also showed positivity to other inhalant pollen allergens tested. CONCLUSION: IgE mediated hypersensitivity varied from 4.40% to 13.20% in Indian atopic subjects to pollen of one or the other species of Brassica. Protein fractions of 47, 56, 76, 87, and 90 kDa were identified as IgE binding by all the four species, however individual heterogeneity exists. Thus a local species may be more pertinent for immunotherapy. The major allergen needs to be further characterized.
Allergens ; Blotting, Western ; Brassica napus ; Brassica ; Electrophoresis ; Galectin 3 ; Humans ; Hypersensitivity ; Hypersensitivity, Immediate ; Immunoglobulin E ; Immunotherapy ; India ; Mustard Plant ; Pollen ; Population Characteristics ; Skin ; Sodium

The well-known detrimental effects of cadmium (Cd) on plants are chloroplast destruction, photosynthetic pigment inhibition, imbalance of essential plant nutrients, and membrane damage. Jasmonic acid (JA) is an alleviator against different stresses such as salinity and drought. However, the functional attributes of JA in plants such as the interactive effects of JA application and Cd on rapeseed in response to heavy metal stress remain unclear. JA at 50 µmol/L was observed in literature to have senescence effects in plants. In the present study, 25 µmol/L JA is observed to be a "stress ameliorating molecule" by improving the tolerance of rapeseed plants to Cd toxicity. JA reduces the Cd uptake in the leaves, thereby reducing membrane damage and malondialdehyde content and increasing the essential nutrient uptake. Furthermore, JA shields the chloroplast against the damaging effects of Cd, thereby increasing gas exchange and photosynthetic pigments. Moreover, JA modulates the antioxidant enzyme activity to strengthen the internal defense system. Our results demonstrate the function of JA in alleviating Cd toxicity and its underlying mechanism. Moreover, JA attenuates the damage of Cd to plants. This study enriches our knowledge regarding the use of and protection provided by JA in Cd stress.
Brassica napus/metabolism* ; Cadmium/toxicity* ; Catalase/metabolism* ; Cyclopentanes/pharmacology* ; Oxylipins/pharmacology* ; Photosynthesis ; Plant Leaves/metabolism* ; Superoxide Dismutase/metabolism*