By screening for ethylene response mutants in Arabidopsis, a novel mutant, eer2, was isolated which 0displays enhanced ethylene responses. On a low nutrient medium (LNM) light-grown eer2 seedlings showed a significant hypocotyl elongation in response to low levels of 1-amino-cyclopropane-1-carboxylate (ACC), the precursor of ethylene, compared with the wild type, indicating that eer2 is hypersensitive to ethylene. Treatment with 1-MCP (1-methylcyclopropene), a competitive inhibitor of ethylene signalling, suppressed this hypersensitive response, demonstrating that it is a bona fide ethylene effect. By contrast, roots of eer2 were less sensitive than the wild type to low concentrations of ACC. The ethylene levels in eer2 did not differ from the wild type, indicating that ethylene over-production is not the primary cause of the eer2 phenotype. In addition to its enhanced ethylene response of hypocotyls, eer2 is also affected in the pattern of senescence and its phenotype depends on the nutritional status of the growth medium. Furthermore, linkage analysis of eer2 suggests that this mutant defines a new locus in ethylene signalling.
|Number of pages||12|
|Journal||Journal of Experimental Botany|
|State||Published - Sep 2005|
Bibliographical noteFunding Information:
We thank Peter Lootens and Paul Vandecasteele from the Agricultural Research Centre in Merelbeke for the training and use of the portable fluorometer PAM-2000, Mira Haegman and Piet Vankeirsbilck for technical assistance with the ethylene measurements, Jan Goeman and Johan Vandereycken for supplying 1-MCP, Andrea Miyasaka de Almeida for critical reading, and Tom Gerats, Janny Peeters, and Marnik Vuylsteke for helpful discussions. This work was supported by a PhD fellowship to Annelies De Paepe and research grants to Dominique Van Der Straeten (G.0281.98, WO.004.99, and G.0345.02) from the Fund for Scientific Research (Flanders).
- Enhanced response
- Metal transport
- Metal uptake
ASJC Scopus subject areas
- Plant Science