CLONING AND CHARACTERIZATION OF MEK1, AN ARABIDOPSIS GENE ENCODING A HOMOLOG OF MAP KINASE KINASE

We report the cloning of a cDNA for MEK1, an Arabidopsis thaliana gene encoding a homologue of MAP kinase kinase (MEK). The predicted protei n sequence shows 41% identity over 270 amino acids to vertebrate MEK p roteins, and contains conserved features characteristic of MEK. Analys is of transcript levels show that expression of the gene is regulated by developmental processes (etiolation/de-etiolation) and by wounding. However in contrast to the rapid wound induction of MAP kinase transc ripts in other plant species, MEK1 transcripts first accumulated 6-12 h after wounding.