Ethylene perception by the ERS1 protein in Arabidopsis.
Ethylene perception in Arabidopsis is controlled by a family of five genes, including ETR1, ERS1 (ethylene response sensor 1), ERS2, ETR2, and EIN4. ERS1, the most highly conserved gene with ETR1, encodes a protein with 67% identity to ETR1. To clarify the role of ERS1 in ethylene sensing, we biochemically characterized the ERS1 protein by heterologous expression in yeast. ERS1, like ETR1, forms a membrane-associated, disulfide-linked dimer. In addition, yeast expressing the ERS1 protein contains ethylene-binding sites, indicating ERS1 is also an ethylene-binding protein. This finding supports previous genetic evidence that isoforms of ETR1 also function in plants as ethylene receptors. Further, we used the ethylene antagonist 1-methylcyclopropene (1-MCP) to characterize the ethylene-binding sites of ERS1 and ETR1. We found 1-MCP to be both a potent inhibitor of the ethylene-induced seedling triple response, as well as ethylene binding by yeast expressing ETR1 and ERS1. Yeast expressing ETR1 and ERS1 showed nearly identical sensitivity to 1-MCP, suggesting that the ethylene-binding sites of ETR1 and ERS1 have similar affinities for ethylene.
Department of Botany, University of Wisconsin, Madison, Wisconsin 53706, USA.
A E
AE
Hall
J L
JL
Findell
G E
GE
Schaller
E C
EC
Sisler
A B
AB
Bleecker
D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins; D003521:Cyclopropanes / Q000494:pharmacology; D005030:Ethylenes / Q000378:metabolism*; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism
D029681:Arabidopsis Proteins; D003521:Cyclopropanes; C095706:ERS protein, Arabidopsis; D005030:Ethylenes; D010940:Plant Proteins; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; C083750:ethylene receptors, plant; C036216:ethylene; D005982:Glutathione Transferase; C412563:1-methylcyclopropene