Open AccessIdentification of genes differentially expressed in the phytopathogenic fungus Cercospora nicotianae between cercosporin toxin‐resistant and ‐susceptible strains
Author(s) -
Herrero Sonia,
Amnuaykanjanasin Alongkorn,
Daub Margaret E.
Publication year - 2007
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2007.00903.x
Subject(s) - biology , suppression subtractive hybridization , cercospora , gene , microbiology and biotechnology , expressed sequence tag , mutant , toxin , genetics , gene expression , leaf spot , botany , cdna library
Plant pathogens from the genus Cercospora produce cercosporin, a photoactivated fungal toxin that generates toxic reactive oxygen species. Mechanisms governing toxin auto‐resistance in Cercospora spp. are poorly understood. In this work, suppressive subtractive hybridization was used to identify genes differentially expressed between the cercosporin‐resistant wild‐type (WT) Cercospora nicotianae and a sensitive strain lacking a transcription factor (CRG1) that regulates resistance. Out of 338 sequences recovered, 185 unique expressed sequence tags (ESTs) were obtained and classified into functional categories. The majority of genes showed predicted expression differences, and 38.5% were differentially expressed at least twofold between the WT and mutant strain. ESTs were recovered with homology to genes involved in detoxification of noxious compounds, multidrug membrane transporters and antioxidant and polyketide biosynthetic enzymes as well as to ATPases and ATP synthases. The findings suggest that CRG1 regulates genes involved in pH responses in addition to those involved in toxin resistance and biosynthesis.