7 research outputs found
Field performance of "marsh seedless" grapefruit on trifoliate orange inoculated with viroids in Brazil
Sequence Analysis Of 22 Kda-like α-coixin Genes And Their Comparison With Homologous Zein And Kafirin Genes Reveals Highly Conserved Protein Structure And Regulatory Elements
Several genomic and cDNA clones encoding the 22 kDa-like α-coixin, the α-prolamin of Coix seeds, were isolated and sequenced. Three contiguous 22 kDa-like α-coixin genes designated α-3A, α-3B and α-3C were found in the 15 kb α-3 genomic clone. The α-3A and α-3C genes presented in-frame stop codons at position +652. The two genes with truncated ORFs are flanking the α-3B gene, suggesting that the three α-coixin genes may have arisen by tandem duplication and that the stop codon was introduced before the duplication. Comparison of the deduced amino acid sequences of α-coixin clones with the published sequences of 22 kDa α-zein and 22 kDa-like α-kafirin revealed a highly conserved protein structure. The protein consists of an N-terminus, containing the signal peptide, followed by ten highly conserved tandem repeats of 15-20 amino acids flanked by polyglutamines, and a short C-terminus. The difference between the 22 kDa-like α-prolamins and the 19 kDa α-zein lies in the fact that the 19 kDa protein is exactly one repeat motif shorter than the 22 kDa proteins. Several putative regulatory sequences common to the zein and kafirin genes were identified within both the 5âČ and 3âČ flanking regions of α-3B. Nucleotide sequences that match the consensus TATA, CATC and the ca. -300 prolamin box are present at conserved positions in α-3B relative to zein and kafirin genes. Two putative Opaque-2 boxes are present in α-3B that occupies approximately the same positions as those identified for the 22 kDa α-zein and α-kafirin genes. Southern hybridization, using a fragment of a maize Opaque-2 cDNA clone as a probe, confirmed the presence of Opaque-2 homologous sequences in the Coix and sorghum genomes. The overall results suggest that the structural and regulatory genes involved in the expression of the 22 kDa-like α-prolamin genes of Coix, sorghum and maize, originated from a common ancestor, and that variations were introduced in the structural and regulatory sequences after species separation. © 1993 Kluwer Academic Publishers.21576577
Polyclonal antibodies to the coat protein of Apple stem grooving virus expressed in Escherichia coli: production and use in immunodiagnosis
Expression of Grapevine leafroll-associated virus 3 coat protein gene in Escherichia coli and production of polyclonal antibodies
Characterization of Citrus tristeza virus isolates from grapefruit (Citrus paradisi Macf.) accessions of Citrus Active Germplasm Bank Caracterização de isolados do vĂrus da tristeza dos citros de acessos de pomelos (Citrus paradisi Macf.) do Banco Ativo de Germoplasma de Citros
Citrus tristeza virus (CTV) isolates from 35 grapefruit accessions belonging to Citrus Active Germplasm Bank of the "Instituto AgronĂŽmico de Campinas" located at the "Centro APTA Citros Sylvio Moreira", CordeirĂłpolis, SĂŁo Paulo state, Brazil, were characterized and evaluated through symptoms in the trees, biological indexing, immunological diagnosis with different monoclonal antibodies and SSCP analysis (single-strand conformation polymorphism) of the coat protein gene. Symptomatology indicated that, in general, the group of plants with smaller canopy volume and severe stem pitting differed significantly from the group that presented greater vegetative development and mild to moderate stem pitting. However, the isolates from most of the accessions induced mild reaction on Mexican lime. The serological evaluation through the DAS-ELISA using monoclonal antibodies did not reveal any association between virus titer in the plant tissue and symptoms. The reaction with different monoclonal antibodies and the distinct electrophoresis patterns obtained through SSCP showed that there is a high degree of diversity among the isolates that infect these grapefruit accessions. High complexity within the same isolate was also observed in the SSCP profiles. This finding indicates that the CTV isolates from these plants are a complex mixture of CTV haplotypes. Similar SSCP banding patterns were observed among some plants with strong stem pitting symptoms, and among some plants with weak or moderate stem pitting symptoms.<br>Isolados do vĂrus da tristeza dos citros (CTV) de 35 acessos de pomelos que fazem parte do Banco Ativo de Germoplasma de Citros, localizado no Centro APTA Citros Sylvio Moreira, CordeirĂłpolis, SĂŁo Paulo, Brasil, pertencente ao Instituto AgronĂŽmico de Campinas (IAC), foram caracterizados atravĂ©s dos sintomas observados nas ĂĄrvores, indexação biolĂłgica, diagnĂłstico imunolĂłgico e anĂĄlise SSCP (polimorfismo de conformação de fita simples) do gene da proteĂna do capsĂdeo. O grupo de plantas que, em geral, apresentou menor volume de copa e severo sintoma de canelura diferenciou-se significativamente do grupo com maior desenvolvimento vegetativo e fraco a moderado sintoma de canelura. No entanto, a maioria dos isolados de CTV das plantas de ambos os grupos induziu fraca reação em limĂŁo galego e nenhuma relação entre tĂtulos do vĂrus nos tecidos e sintomatologia foi observada na avaliação sorolĂłgica conduzida por DAS-ELISA. A reação com diferentes anticorpos monoclonais e os distintos padrĂ”es eletroforĂ©ticos obtidos por SSCP demonstraram que hĂĄ uma grande diversidade entre os isolados de CTV que infectam os acessos de pomelos. Alta complexidade de bandas dentro de um mesmo isolado foi tambĂ©m observada nos perfis SSCP, demonstrando que cada isolado Ă© constituĂdo por uma mistura de diferentes haplĂłtipos de CTV. PadrĂ”es SSCP semelhantes foram observados entre algumas plantas com fortes sintomas de caneluras e entre algumas plantas com sintomas fracos ou moderados de caneluras