title: Post-transcriptional silencing of the SGE1 gene induced by a dsRNA hairpin in Fusarium oxysporum f. sp cubense, the causal agent of Panama disease.
abstract: Fusarium oxysporum f. sp cubense (Foc), the causal agent of Panama disease, is responsible for economic losses in banana crops worldwide. The identification of genes that effectively act on pathogenicity and/or virulence may contribute to the development of different strategies for disease control and the production of resistant plants. The objective of the current study was to analyze the importance of SGE1 gene expression in Foc virulence through post-transcriptional silencing using a double-stranded RNA hairpin. Thirteen transformants were selected based on different morphological characteristics, and sporulation in these transformants was significantly reduced by approximately 95% (P < 0.05) compared to that of the wild-type strain. The relative SGE1 expression levels in the transformant strains were reduced by 27 to 47% compared to those in the wild-type strain. A pathogenicity analysis revealed that the transformants were able to reach the rhizomes and pseudostems of the inoculated banana plants. However, the transformants induced initial disease symptoms in the banana plants approximately 10 days later than that by the wild-type Foc, and initial disease symptoms persisted even at 45 days after inoculation. These results indicate that the SGE1 gene is directly involved in the virulence of Foc. Therefore, SGE1 may be a potential candidate for host-induced gene silencing in banana plants.
authors.affiliation: Laboratório de Biologia Molecular, Embrapa Amazônia Ocidental, Manaus, AM, Brasil.
authors.forename: J S
authors.initials: JS
authors.lastname: Fernandes
authors.affiliation: Embrapa Café - Fundação Procafé, Varginha, MG, Brasil.
authors.forename: P C S
authors.initials: PC
authors.lastname: Angelo
authors.affiliation: Laboratório de Biologia Molecular, Embrapa Amazônia Ocidental, Manaus, AM, Brasil.
authors.forename: J C
authors.initials: JC
authors.lastname: Cruz
authors.affiliation: Instituto Nacional de Pesquisa da Amazônia & Universidade do Estado do Amazonas, Manaus, AM, Brasil.
authors.forename: J M M
authors.initials: JM
authors.lastname: Santos
authors.affiliation: Embrapa Cocais, São Luiz, MA, Brasil.
authors.forename: N R
authors.initials: NR
authors.lastname: Sousa
authors.affiliation: Laboratório de Biologia Molecular, Embrapa Amazônia Ocidental, Manaus, AM, Brasil.
authors.forename: G F
authors.initials: GF
authors.lastname: Silva
mesh_terms: D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D005670:Fusarium / Q000235:genetics* / Q000472:pathogenicity; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D014774:Virulence / Q000235:genetics
chemical_list: D005656:Fungal Proteins; D034741:RNA, Small Interfering