Isolation and biochemical analysis of ethyl methanesulfonate-induced alcohol dehydrogenase null mutants ofArabidopsis thaliana (L.) Heynh

Several mutants have been isolated at theArabidopsis thaliana (L.) Heynh. alcohol dehydrogenase (ADH) gene locus using allyl alcohol selection on ethyl methanesulfonate (EMS)-mutagenized seeds. Eleven mutants were isolated in theADH1-A electrophoretic allele, and 21 in theADH1-S allele. These null mutants are characterized by the absence of measurable ADH activity and genetic data showed that the mutations were confined to theADH1 gene locus ofArabidopsis. Eleven mutants in theADH1-A background were further characterized at the protein and mRNA level. These experiments revealed striking differences in the ADH protein and mRNA content. Some of the mutants did not synthesize any mRNA or ADH-like protein, whereas some of them had a nearly normal level of ADH protein and mRNA. Others had a very low level of both protein and mRNA. ADH null mutants differed physiologically from the wild type by their higher sensitivity to anaerobic treatment in plants and significantly reduced resistance to acetaldehyde in suspension cultures.This research was supported by the Geconcerteerde Onderzoeksactie, Grant 86/91–103, and the Instituut tot Aanmoediging van het Wetenschappelijk Onderzoek in Nijverheid en Landbouw (IWONL), Grant 4972A.