INVESTIGADORES
CASTAGNARO atilio pedro
artículos
Título:
Novel demonstration of RNAi in citrus reveals importance of citrus callose synthase in defence against Xanthomonas citri subsp. citri
Autor/es:
ENRIQUE, R.; SICILIANO; F.; FAVARO, M.A.; GERHARDT, N.; ROESCHLIN, R.; RIGANO, L.; SENDIN, L.; CASTAGNARO, A.P.; VOJNOV, A.; MARANO, M.R.
Revista:
PLANT BIOTECHNOLOGY JOURNAL
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Lugar: Londres; Año: 2010 p. 1 - 14
ISSN:
1467-7644
Resumen:
Citrus is an economically important fruit crop that is severely afflicted by citrus canker,a disease caused by the bacterial phytopathogen, Xanthomonas citri subsp. citri(Xcc). GenBank houses a large collection of Expressed Sequence Tags (ESTs) enrichedwith transcripts generated during the defence response against this pathogen; however,there are currently no strategies in citrus to assess the function of candidategenes. This has greatly limited research as defence signalling genes are ofteninvolved in multiple pathways. In this study, we demonstrate the efficacy of RNAinterference (RNAi) as a functional genomics tool to assess the function of candidategenes involved in the defence response of Citrus limon against the citrus cankerpathogen. Double-stranded RNA expression vectors, encoding hairpin RNAs for citrushost genes, were delivered to lemon leaves by transient infiltration with transformedAgrobacterium. As proof of principle, we have established silencing of citrus phytoenedesaturase (PDS) and callose synthase (CalS1) genes. Phenotypic and molecularanalyses showed that silencing vectors were functional not only in lemon plants butalso in other species of the Rutaceae family. Using silencing of CalS1, we have demonstratedthat plant cell wall-associated defence is the principal initial barrier againstXanthomonas infection in citrus plants. Additionally, we present here results thatsuggest that H2O2 accumulation, which is suppressed by xanthan from Xcc duringpathogenesis, contributes to inhibition of xanthan-deficient Xcc mutant growtheither in wild-type or CalS1-silenced plants. With this work, we have demonstratedthat high-throughput reverse genetic analysis is feasible in citrus.