Poster: Signaling, long distance

Abs # 454: Characterization of ethylene receptor signaling complexes from Arabidopsis

Presenter:	Gao, Zhiyong , zhiyongg@yahoo.com
Authors	Gao, Zhiyong  (A)   Chen, Yi-feng  (A)   Schaller, G. Eric  (A)
Affiliations:	(A): Dartmouth College, Dept. of Biological Sciences

The plant hormone ethylene is perceived by a five member family of receptors (ETR1, ERS1, ETR2, ERS2, EIN4) in Arabidopsis. The Raf-like kinase CTR1 functions downstream of the ethylene receptors in the ethylene signal transduction pathway. Analysis by gel-filtration indicates that ETR1 is part of a stable 670 KDa complex. Direct evidence that CTR1 is part of the ETR1 signaling complex was obtained by co-purification of ETR1 with a tagged version of CTR1 from an Arabidopsis membrane extract. The ETR1 complex was further characterized by analysis of various mutants as well as truncated versions of the receptor. The truncations serve to define which regions of ETR1 are involved in forming the signaling complex. The sizes of the signaling complexes formed by other member of the ethylene receptor family are being determined. Study on the signaling complexes of ethylene receptors will help to elucidate the mechanism of ethylene signal transduction.