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Functional expression of a probable Arabidopsis thaliana potassium channel in Saccharomyces cerevisiae.

ABSTRACT: We report the isolation of a cDNA (KAT1) from Arabidopsis thaliana that encodes a probable K+ channel. KAT1 was cloned by its ability to suppress a K+ transport-defective phenotype in mutant Saccharomyces cerevisiae cells. This suppression is sensitive to known K+ channel blockers, including tetraethylammonium and Ba2+ ions. The KAT1 cDNA contains an open reading frame capable of encoding a 78-kDa protein that shares structural features found in the Shaker superfamily of K+ channels. These include a cluster of six putative membrane-spanning helices (S1-S6) at the amino terminus of the protein, a presumed voltage-sensing region containing Arg/Lys-Xaa-Xaa-Arg/Lys repeats within S4, and the highly conserved pore-forming region (known as H5 or SS1-SS2). Our results suggest that the structural motif for K+ channels has been conserved between plants and animals.

SUBMITTER: Anderson JA

PROVIDER: S-EPMC525565 | biostudies-other | 1992 May

REPOSITORIES: biostudies-other

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Functional expression of a probable Arabidopsis thaliana potassium channel in Saccharomyces cerevisiae.

Anderson J A JA Huprikar S S SS Kochian L V LV Lucas W J WJ Gaber R F RF

Proceedings of the National Academy of Sciences of the United States of America 19920501 9

We report the isolation of a cDNA (KAT1) from Arabidopsis thaliana that encodes a probable K+ channel. KAT1 was cloned by its ability to suppress a K+ transport-defective phenotype in mutant Saccharomyces cerevisiae cells. This suppression is sensitive to known K+ channel blockers, including tetraethylammonium and Ba2+ ions. The KAT1 cDNA contains an open reading frame capable of encoding a 78-kDa protein that shares structural features found in the Shaker superfamily of K+ channels. These inclu ...[more]

PMID: 1570292

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