Insensitivity to Ethylene Conferred by a Dominant Mutation in <i>Arabidopsis thaliana</i>

TLDR

Ethylene influences diverse developmental processes and stress responses in higher plants, and these responses in Arabidopsis appear to share a common transduction element, such as a single receptor. The molecular basis for ethylene action was investigated in Arabidopsis thaliana mutants with altered ethylene responses. A dominant etr mutant line lacks several ethylene responses seen in wild‑type Arabidopsis—including inhibition of cell elongation, promotion of seed germination, enhancement of peroxidase activity, acceleration of leaf senescence, and feedback suppression of ethylene synthesis—and in vivo ethylene‑binding assays suggest the receptor is affected by the mutation.

Abstract

Ethylene influences a number of developmental processes and responses to stress in higher plants. The molecular basis for the action of ethylene was investigated in mutants of Arabidopsis thaliana that have altered responses to ethylene. One mutant line, which has a dominant mutation at a locus designated etr, lacks a number of responses to ethylene that are present in the wild-type plant. These include inhibition of cell elongation, promotion of seed germination, enhancement of peroxidase activity, acceleration of leaf senescence, and feedback suppression of ethylene synthesis by ethylene. These diverse responses, which occur in different tissues of Arabidopsis, appear to share some common element in their transduction pathways-for example, a single receptor for ethylene. Results of ethylene binding experiments in vivo indicate that this receptor may be affected by the etr mutation.