Regulatory elements mediating expression of xylanase genes in Fusarium oxysporum.
The role of DNA regulatory elements mediating activation of the xylanase-encoding gene xyl4 by the transcription factor XlnR in the fungal pathogen Fusarium oxysporum, was studied by in vitro and in vivo functional analysis of the xyl4 promoter. Recombinant XlnR protein specifically bound the sequence GGCTAA in electrophoretic mobility shift assays. Experiments with xyl4 promoter fusions with the lacZ reporter gene showed that the GGCTAA sequence is required for xylan-induced transcriptional activation of xyl4 in F. oxysporum. The results support a model in which the interaction between the transcriptional activator XlnR and an unknown constitutive repressor regulates xylanase gene expression in F. oxysporum.
Departamento de Genética, Universidad de Córdoba, Campus Universitario de Rabanales, Edif C5, E-14071 Córdoba, Spain.
Fernando
F
Calero-Nieto
Concepción
C
Hera
Antonio
A
Di Pietro
Margarita
M
Orejas
M Isabel G
MI
Roncero
D024202:Electrophoretic Mobility Shift Assay; D004742:Enhancer Elements, Genetic / Q000502:physiology*; D005656:Fungal Proteins / Q000235:genetics*; D005670:Fusarium / Q000235:genetics*; D005786:Gene Expression Regulation; D005800:Genes, Fungal; D018551:Solanum lycopersicum / Q000382:microbiology; D010935:Plant Diseases / Q000382:microbiology; D050436:Regulatory Elements, Transcriptional / Q000235:genetics; D014995:Xylosidases / Q000235:genetics*
D005656:Fungal Proteins; D014995:Xylosidases