@article{amnuaykanjanasin_daub_2009, title={The ABC transporter ATR1 is necessary for efflux of the toxin cercosporin in the fungus Cercospora nicotianae}, volume={46}, ISSN={["1096-0937"]}, DOI={10.1016/j.fgb.2008.11.007}, abstractNote={The Cercospora nicotianae mutant deficient for the CRG1 transcription factor has marked reductions in both resistance and biosynthesis of the toxin cercosporin. We cloned and sequenced full-length copies of two genes, ATR1 and CnCFP, previously identified from a subtractive library between the wild type (WT) and a crg1 mutant. ATR1 is an ABC transporter gene and has an open reading frame (ORF) of 4368 bp with one intron. CnCFP encodes a MFS transporter with homology to Cercospora kikuchii CFP, previously implicated in cercosporin export, and has an ORF of 1975 bp with three introns. Disruption of ATR1 indicated atr1-null mutants had dramatic reductions in cercosporin production (25% and 20% of WT levels) in solid and liquid cultures, respectively. The ATR1 disruptants also showed moderately higher sensitivity to cercosporin. Constitutive expression of ATR1 in the crg1 mutant restored cercosporin biosynthesis and moderately increased resistance. In contrast, CnCFP overexpression in the mutant did not restore toxin production, however, it moderately enhanced toxin resistance. The results together indicate ATR1 acts as a cercosporin efflux pump in this fungus and plays a partial role in resistance.}, number={2}, journal={FUNGAL GENETICS AND BIOLOGY}, author={Amnuaykanjanasin, Alongkom and Daub, Margaret E.}, year={2009}, month={Feb}, pages={146–158} }
 @article{herrero_amnuaykanjanasin_daub_2007, title={Identification of genes differentially expressed in the phytopathogenic fungus Cercospora nicotianae between cercosporin toxin-resistant and -susceptible strains}, volume={275}, ISSN={["1574-6968"]}, DOI={10.1111/j.1574-6968.2007.00903.x}, abstractNote={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.}, number={2}, journal={FEMS MICROBIOLOGY LETTERS}, author={Herrero, Sonia and Amnuaykanjanasin, Alongkorn and Daub, Margaret E.}, year={2007}, month={Oct}, pages={326–337} }