A Potassium Channel Protein Encoded by Chlorella Virus PBCV-1

Authors

B. Plugge, Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Universität Göttingen, 37073 Göttingen, Germany
S. Gazzarrini, Università degli Studi di Milano, 20133 Milan, Italy
M. Nelson, Megabase Research Products, Lincoln, NE
R. Cerana, DISAT, Università di Milano Bicocca, 20126 Milan, Italy
James L. Van Etten, University of Nebraska-LincolnFollow
C. Derst, Institut für Physiologie, Philipps-Universität Marburg, 35033 Marburg, Germany
D. DiFrancesco, Università degli Studi di Milano, 20133 Milan, Italy
A. Moroni, Università degli Studi di Milano, 20133 Milan, Italy
G. Thiel, Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Universität Göttingen, 37073 Göttingen, GermanyFollow

Document Type

Article

Date of this Version

3-3-2000

Comments

Published in Science 287 (March 3, 2000), pp. 1641–1644; doi 10.1126/science.287.5458.1641 Copyright © 2000 by the American Association for the Advancement of Science. Used by permission. http://www.sciencemag.org

Abstract

The large chlorella virus PBCV-1, which contains double-stranded DNA (dsDNA), en¬codes a 94-codon open reading frame (ORF) that contains a motif resembling the signature se¬quence of the pore domain of potassium channel proteins. Phylogenetic analyses of the encoded protein, Kcv, indicate a previously unidentified type of potassium channel. The messenger RNA encoded by the ORF leads to functional expression of a potassium-selective conductance in Xen¬opus laevis oocytes. The channel blockers amantadine and barium, but not cesium, inhibit this conductance, in addition to virus plaque formation. Thus, PBCV-1 encodes the first known viral protein that functions as a potassium-selective channel and is essential in the virus life cycle.