Mutations Affecting Induction of Glycolytic and Fermentative Genes during Germination and Environmental Stresses in Arabidopsis1

Abstract

Expression of the alcohol dehydrogenase gene (ADH) of Arabidopsis is known to be induced by environmental stresses and regulated developmentally. We used a negative-selection approach to isolate mutants that were defective in regulating the expression of theADH gene during seed germination; we then characterized three recessive mutants, aar1–1,aar1–2, and aar2–1, which belong to two complementation groups. In addition to their defects during seed germination, mutations in the AAR1 andAAR2 genes also affected anoxic and hypoxic induction ofADH and other glycolytic genes in mature plants. Theaar1 and aar2 mutants were also defective in responding to cold and osmotic stress. The two allelic mutantsaar1–1and aar1–2 exhibited different phenotypes under cold and osmotic stresses. Based on our results we propose that these mutants are defective in a late step of the signaling pathways that lead to increased expression of theADH gene and glycolytic genes.