Level of expression inXenopus oocytes affects some characteristics of a plant inward-rectifying voltage-gated K+ channel
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The plant K+ channel KAT1 shows some similarity to animal voltage-gated channels of the Shaker superfamily. Contrary to these animal counterparts, this plant channel is inwardly rectifying, being gated upon hyperpolarization. Different levels of expression of KAT1 inXenopus oocytes could be obtained by increasing the amount of injected cRNA. The resulting KAT1 gating and sensitivity to external caesium were significantly changed. Similar findings have been published regarding animal voltage-gated channels. The present data show that plant channels may also undergo modification of their activity upon modification of their level of expression.
Key wordspotassium channels Arabidopsis thaliana Xenopus oocytes activation kinetics caesium blockade
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- 1.Anderson JA, Huprikar SS, Kochian LV, Lucas WJ, Gaber RF (1992) Functional expression of a probableArabidopsis thaliana potassium channel inSaccharomyces cerevisiae. Proc Natl Acad Sci USA 89:3736–3740Google Scholar
- 2.Hille B (1992) Ionic channels of excitable membranes (2nd Ed.) Sinauer Associates, Sunderland, Massachusetts, 607 ppGoogle Scholar
- 3.Honoré E, Attali B, Romey G, Lesage F, Barhanin J, Lazdunski M (1992) Different types of K+ channel current are generated by different levels of a single mRNA. EMBO J 11:2465–2470Google Scholar
- 4.Ito Y, Yokoyama S, Higashida H (1992) Potassium channels cloned from neuroblastoma cells display slowly inactivating outward currents inXenopus oocytes. Proc R Soc Lond B 248:95–101Google Scholar
- 5.Moran O, Schreibmayer W, Weigl L, Dascal N, Lotan I (1992) Level of expression controls modes of gating of a K+ channel. FEBS Lett 302:21–25Google Scholar
- 6.Schachtman DP, Schroeder JI, Lucas WJ, Anderson JA, Gaber RF (1992) Expression of inward-rectifying potassium channel by theArabidopsis KAT1 cDNA. Science 258:1654–1658Google Scholar
- 7.Sentenac H, Bonneaud N, Minet M, Lacroute F, Salmon JM, Gaymard F, Grignon C (1992) Cloning and expression in yeast of a plant potassium ion transport system. Science 256:663–665Google Scholar
- 8.Tester M (1990) Plant ion channels: whole-cell and single-channel studies. New Phytol 114:305–340Google Scholar