RESUMEN
The Dothideomycete fungus Mycosphaerella graminicola is the causal agent of Septoria tritici blotch, a devastating disease of wheat leaves that causes dramatic decreases in yield. Infection involves an initial extended period of symptomless intercellular colonisation prior to the development of visible necrotic disease lesions. Previous functional genomics and gene expression profiling studies have implicated the production of secreted virulence effector proteins as key facilitators of the initial symptomless growth phase. In order to identify additional candidate virulence effectors, we re-analysed and catalogued the predicted protein secretome of M. graminicola isolate IPO323, which is currently regarded as the reference strain for this species. We combined several bioinformatic approaches in order to increase the probability of identifying truly secreted proteins with either a predicted enzymatic function or an as yet unknown function. An initial secretome of 970 proteins was predicted, whilst further stringent selection criteria predicted 492 proteins. Of these, 321 possess some functional annotation, the composition of which may reflect the strictly intercellular growth habit of this pathogen, leaving 171 with no functional annotation. This analysis identified a protein family encoding secreted peroxidases/chloroperoxidases (PF01328) which is expanded within all members of the family Mycosphaerellaceae. Further analyses were done on the non-annotated proteins for size and cysteine content (effector protein hallmarks), and then by studying the distribution of homologues in 17 other sequenced Dothideomycete fungi within an overall total of 91 predicted proteomes from fungal, oomycete and nematode species. This detailed M. graminicola secretome analysis provides the basis for further functional and comparative genomics studies.
Asunto(s)
Ascomicetos/metabolismo , Proteínas Fúngicas/metabolismo , Enfermedades de las Plantas/microbiología , Triticum/microbiología , Ascomicetos/genética , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión GénicaRESUMEN
Xanthomonas citri ssp. citri (Xcc) is the causal agent of citrus canker. This bacterium develops a characteristic biofilm on both biotic and abiotic surfaces. A biofilm-deficient mutant was identified in a screening of a transposon mutagenesis library of the Xcc 306 strain constructed using the commercial Tn5 transposon EZ-Tn5
Asunto(s)
Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Glucanos/biosíntesis , Xanthomonas/fisiología , Xanthomonas/patogenicidad , Proteínas Bacterianas/genética , Biopelículas/efectos de los fármacos , Citrus/efectos de los fármacos , Citrus/microbiología , Flagelos/efectos de los fármacos , Flagelos/fisiología , Genes Bacterianos/genética , Peróxido de Hidrógeno/farmacología , Viabilidad Microbiana/efectos de los fármacos , Movimiento/efectos de los fármacos , Mutación/genética , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/microbiología , Virulencia/efectos de los fármacos , Xanthomonas/efectos de los fármacos , Xanthomonas/genéticaRESUMEN
The progeny of 87 BC(1) hybrids of 'Murcott' tangor and 'Pera' sweet orange, genotyped with fluorescent amplified fragment length polymorphism (fAFLP) markers, was used for the construction of genetic maps for both citrus varieties. Mapping strategies, considering the progeny as a result of backcrossing and cross-pollination, were exploited in Mapmaker 2.0 (LOD score >or= 3.0 and Asunto(s)
Mapeo Cromosómico
, Cromosomas de las Plantas/genética
, Citrus sinensis/genética
, Ligamiento Genético
, Marcadores Genéticos
, Técnica del ADN Polimorfo Amplificado Aleatorio
, Genes de Plantas
, Escala de Lod
, Sitios de Carácter Cuantitativo