The clear differentiation among ‘Candidatus Phytoplasma asteris’-related strains using Amp-N1/C1 primers amplifying the amp gene was observed in samples classified into different 16SrI subgroups (16SrI-A, I-B, I-C, I-L, and I-M). Samples were maintained in periwinkle or collected from field infected plants and insects; in 27 out of the 31 strains employed the full amp gene was also sequenced. Carrot with yellows symptoms and Macrosteles sexnotatus from the same field in Serbia (16SrI-A, 16SrI-B, and 16Sr-I subgroup not identified); poplar with witches’ broom collected in Serbia (16SrI-P); corn and oil palm samples (16SrI-B) from Colombia showing respectively stunt and decline symptoms were also employed. The amp gene could not be amplified in 16SrI-F and I-P strains; in 16SrI-B, I-L, I-M and in the strain from carrot in a not identified subgroup a 740 bp amplicon was obtained; strains in subgroups 16SrI-A, and I-C produced a 650 bp amplicon. RFLP analyses with TruI and Tsp509I enzymes distinguished up to four different profiles in amplicons from16SrI-B, I-L I-M strains, two profiles in 16SrI-A, while an unique profile was present in 16SrI-C strains. Among the field collected samples the M. sexnotatus sample showed a profile different from those obtained in strains from carrots, but referable to one of those of 16SrI-B phytoplasmas in periwinkle. RFLP profiles of corn and oil palm strains were identical to each others and to the one of 16Sr-I strain carrot. The full sequence of amp gene obtained was also studied with translated nucleotide query using NCBI/BLAST/blastx program. Preliminary results indicate that strains in subgroups 16SrI-A, I-C and I-F and strains DAY, AVUT and PrG in 16SrI-B are the less homologous to strains available in GenBank. The phylogenetic analyses of translated sequences confirmed these results, and showed a further differentiation of strains GLAWC, and PRIVA from the majority of 16SrI-B strains sequenced, and the I-P strain from populus was very different from all the others. Further research could clarify possible relationship between amp gene, plant host and insect vector towards molecular epidemiology study of ‘Ca. P asteris’-related phytoplasmas.
Bertaccini A., S. Kakizawa, S. Paltrinieri, B. Duduk, J. Mitrovic, J.F. Mejia, et al. (2010). Molecular comparison of amp gene from several 'Candidatus Phytoplasma asteris' strains. BOLOGNA : sine nomine.
Molecular comparison of amp gene from several 'Candidatus Phytoplasma asteris' strains
BERTACCINI, ASSUNTA;PALTRINIERI, SAMANTA;DUDUK, BOJAN;CONTALDO, NICOLETTA;
2010
Abstract
The clear differentiation among ‘Candidatus Phytoplasma asteris’-related strains using Amp-N1/C1 primers amplifying the amp gene was observed in samples classified into different 16SrI subgroups (16SrI-A, I-B, I-C, I-L, and I-M). Samples were maintained in periwinkle or collected from field infected plants and insects; in 27 out of the 31 strains employed the full amp gene was also sequenced. Carrot with yellows symptoms and Macrosteles sexnotatus from the same field in Serbia (16SrI-A, 16SrI-B, and 16Sr-I subgroup not identified); poplar with witches’ broom collected in Serbia (16SrI-P); corn and oil palm samples (16SrI-B) from Colombia showing respectively stunt and decline symptoms were also employed. The amp gene could not be amplified in 16SrI-F and I-P strains; in 16SrI-B, I-L, I-M and in the strain from carrot in a not identified subgroup a 740 bp amplicon was obtained; strains in subgroups 16SrI-A, and I-C produced a 650 bp amplicon. RFLP analyses with TruI and Tsp509I enzymes distinguished up to four different profiles in amplicons from16SrI-B, I-L I-M strains, two profiles in 16SrI-A, while an unique profile was present in 16SrI-C strains. Among the field collected samples the M. sexnotatus sample showed a profile different from those obtained in strains from carrots, but referable to one of those of 16SrI-B phytoplasmas in periwinkle. RFLP profiles of corn and oil palm strains were identical to each others and to the one of 16Sr-I strain carrot. The full sequence of amp gene obtained was also studied with translated nucleotide query using NCBI/BLAST/blastx program. Preliminary results indicate that strains in subgroups 16SrI-A, I-C and I-F and strains DAY, AVUT and PrG in 16SrI-B are the less homologous to strains available in GenBank. The phylogenetic analyses of translated sequences confirmed these results, and showed a further differentiation of strains GLAWC, and PRIVA from the majority of 16SrI-B strains sequenced, and the I-P strain from populus was very different from all the others. Further research could clarify possible relationship between amp gene, plant host and insect vector towards molecular epidemiology study of ‘Ca. P asteris’-related phytoplasmas.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
