Characterization of a novel cis-acting element that is responsive to a fungal elicitor in the promoter of a tobacco class I chitinase gene.
The expression of tobacco class I chitinase gene is effectively induced by a fungal elicitor in suspension-cultured tobacco cells. To identify cis-acting DNA elements that respond to the elicitor, a series of promoter constructs of the chitinase gene CHN50 fused to beta-glucuronidase gene was introduced into tobacco cultured cells. Promoter deletion analysis of the chitinase gene CHN50 in transgenic tobacco calli indicated that the DNA region between positions -788 and -345 from the start site of transcription is required for inducibility by the elicitor. A gel mobility shift assay revealed that nuclear factor(s) specifically interacted with the DNA region between positions -574 and -476. Moreover, this novel DNA-binding activity was present in nuclear extracts prepared from elicitor-treated cultured cells but not in extracts from untreated cells. Competitive binding assays and methylation interference experiments showed that the nuclear factor(s) bound specifically to a sequence of 22 bp that extended from positions -539 to -518 and contained a direct repeat of GTCAG spaced by three nucleotides. This motif is a candidate for a cis-acting elicitor-responsive element (ElRE) that is involved in the transcription of the class I chitinase gene.
Fukuda
Y
Y
Division of Plant Molecular Biology, National Institute of Bioscience and Human Technology, Ibaraki, Japan.
Shinshi
H
H
D001483:Base Sequence; D002688:Chitinases / Q000235:genetics*; D004247:DNA / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D017343:Genes, Plant; D005966:Glucuronidase / Q000096:biosynthesis / Q000235:genetics; D008969:Molecular Sequence Data; D010838:Phytophthora / Q000235:genetics*; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012091:Repetitive Sequences, Nucleic Acid; D017384:Sequence Deletion; D014026:Nicotiana / Q000201:enzymology* / Q000235:genetics*; D014162:Transfection
D011993:Recombinant Fusion Proteins; D004247:DNA; D002688:Chitinases; D005966:Glucuronidase