A gene induced by the plant hormone abscisic acid in response to water stress encodes a glycine-rich protein

Abstract

Plant hormones such as abscisic acid (ABA) appear to modulate the responses of plants under adverse conditions ABA has a poorly-understood role in embryogenesis, accumulating in the stages before dessication, and altering the rate of transcription of a specific set of genes. The functions of the proteins encoded by these genes, however, are unknown, and their messenger RNAs decrease again during early germination. No correlation has been established between ABA levels and the induction of particular genes in non-embryonic organs. The level of ABA increases substantially in leaf tissues subjected to water stress10 and thus it has been proposed that ABA mediates plant–water relations1,10. Here we describe the isolation of complementary DNA and genomic clones of a gene that is ABA-inducible in the maize embryo, and whose messenger RNA accumulates in epidermial cells, which is also induced by water stress and wounding in leaves. The deduced protein is rich in glycine. Identification of this gene will contribute to our understanding of the role of ABA.