HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplementary figure Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Google Scholar Articles by Cañero, D. C. Articles by Roncero, M. I. G. PubMed PubMed Citation Articles by Cañero, D. C. Articles by Roncero, M. I. G. Agricola Articles by Cañero, D. C. Articles by Roncero, M. I. G.

Influence of the chloride channel of Fusarium oxysporum on extracellular laccase activity and virulence on tomato plants

Departamento de Genetica, Universidad de Cordoba, Campus de Rabanales, Edif. Gregor Mendel, E-14071 Cordoba, Spain

Correspondence
M. Isabel G. Roncero
ge1gorom{at}uco.es

CLC-type voltage-gated chloride channels are a family of proteins which mediate chloride transport across the plasma and intracellular membranes. A clc1 gene from the vascular wilt fungus Fusarium oxysporum was characterized and disrupted. The predicted Clc1 protein contained highly conserved transmembrane and CBS domains of this protein family and showed significant identities to the Saccharomyces cerevisiae GEF1 and the Cryptococcus neoformans CLC-A chloride channels. Inactivation of clc1 caused a deficiency in laccase activity which was more severe than that found in any of the structural laccase mutants previously described. The addition of copper sulphate to the growth medium resulted in total recovery of extracellular laccase activity in clc1 mutants, although it did not activate transcription of any laccase genes. The pleiotropic phenotype displayed by the Fusarium chloride channel-deficient mutants included a significant delay in the development of disease on tomato plants, with a higher sensitivity to oxidative stress compounds as well as a significant decrease in laccase activity, thus suggesting a possible connection between virulence and the two processes. Nevertheless, we cannot rule out that additional phenotypes present in the clc1 mutants could play an essential role in the full virulence of Fusarium.

The GenBank/EMBL/DDBJ accession number for the gene sequence clc1 is EU030436.

A supplementary sequence alignment is available with the online version of this paper.