抄録
Plants respond to environmental stresses in multiple ways including changing the hormonal responses. The plant hormone auxin controls every aspect of growth and development. However,little is known about the effect of temperature stress on auxin response. To understand the mechanistic basis of cold temperature stress and auxin response, we characterized the root growth of Arabidopsis thaliana at 23°C after pre-incubating the seedlings at 4°C. The time course assay revealed that 8-12 hr pre-incubation at 4°C inhibited the root growth and reduced the gravity response approximately 50% compared to that of untreated controls. The auxin-signaling mutant axr1-3, which shows a reduced gravity response, responded to cold treatment like wild-type indicating that auxin transport rather than auxin signaling mechanism is affected by cold stress. Consistently,the expression of the auxin responsive marker was found to be altered in cold treated plants; accumulating GUS staining in the outer layer cells of the root meristem.
