okadaic-acid and propionic-acid

In order to identify genes that are temporally and spatially regulated during wound response, a cDNA population in mechanically wounded tobacco leaves was screened by the fluorescence differential display method. Of 28 clones initially identified to have altered levels of transcripts within 3 h of wounding, eight were characterized. Although each clone showed a unique pattern of transcript accumulation, one distinct clone was further characterized because of its immediate-early response. Its transcripts began to accumulate 10 min after wounding, reached a maximum level within 1 h and disappeared after 2 h. The response, which occurred repeatably and systemically, was observed by the treatment with propionic acid or erythrosin B, indicating that cytosolic acidification could be one of the signals for immediate-early response of this gene. The cDNA encodes a polypeptide of 513 amino acids with a relative molecular mass of 60,952. The putative polypeptide is rich in lysine (K), glutamic acid (E) and aspartic acid (D), which constitute up to 70% of total amino acids, and was therefore designated as KED. The KED polypeptide is composed of a highly hydrophilic N-terminal region and a relatively hydrophobic C-terminal region, suggesting that KED may function through electrostatic interactions with cellular components.

Topics: Amino Acid Sequence; Cycloheximide; Cytosol; DNA, Complementary; Egtazic Acid; Erythrosine; Gene Expression Regulation, Plant; Genes, Immediate-Early; Immediate-Early Proteins; Kinetics; Molecular Sequence Data; Molecular Weight; Nicotiana; Okadaic Acid; Plant Proteins; Plants, Toxic; Propionates; Sequence Homology, Amino Acid; Staurosporine; Time Factors; Transcription, Genetic