TY - JOUR
T1 - A transcriptomics approach to unveiling the mechanisms of in vitro evolution towards fluconazole resistance of a Candida glabrata Clinical Isolate
AU - Cavalheiro, Mafalda
AU - Costa, Catarina
AU - Silva-Dias, Ana
AU - Miranda, Isabel M.
AU - Wang, Can
AU - Pais, Pedro
AU - Pinto, Sandra N.
AU - Mil-Homens, Dalila
AU - Sato-Okamoto, Michiyo
AU - Takahashi-Nakaguchi, Azusa
AU - Silva, Raquel M.
AU - Mira, Nuno P.
AU - Fialho, Arsénio M.
AU - Chibana, Hiroji
AU - Rodrigues, Acácio G.
AU - Butler, Geraldine
AU - Teixeiraa, Miguel C.
N1 - Funding Information:
This work was supported by FEDER and the “Fundação para a Ciência e a Tecnolo-gia” (FCT) (contracts PTDC/BBB-BIO/4004/2014 and PTDC/BII-BIO/28216/2017 and by Ph.D. and postdoctoral grants to M.C. (PD/BD/116946/2016), P.P. (PD/BD/113631/2015), C.C. (SFRH/BPD/100863/2014), D.M.-H. (SFRH/BPD/91831/2012), S.N.P. (SFRH/BPD/ 92409/2013), and I.M.M. (SFRH/BPD/113285/2015). Funding received from FCT (grant UID/BIO/04565/2013), Programa Operacional Regional de Lisboa 2020 (project no. 007317), and Science Foundation Ireland (grant 12/IA/1343) is also acknowledged. This study was partially supported by a Joint Usage/Research Program of the Medical Mycology Research Center, Chiba University, Chiba, Japan.
Publisher Copyright:
Copyright © 2018 Cavalheiro et al.
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2019/1
Y1 - 2019/1
N2 - Candida glabrata is an emerging fungal pathogen. Its increased prevalence is associated with its ability to rapidly develop antifungal drug resistance, particularly to azoles. In order to unravel new molecular mechanisms behind azole resistance, a transcriptomics analysis of the evolution of a C. glabrata clinical isolate (isolate 044) from azole susceptibility to posaconazole resistance (21st day), clotrimazole resistance (31st day), and fluconazole and voriconazole resistance (45th day), induced by longstanding incubation with fluconazole, was carried out. All the evolved strains were found to accumulate lower concentrations of azole drugs than the parental strain, while the ergosterol concentration remained mostly constant. However, only the population displaying resistance to all azoles was found to have a gain-of-function mutation in the C. glabrata PDR1 gene, leading to the upregulation of genes encoding multidrug resistance transporters. Intermediate strains, exhibiting posaconazole/clotrimazole resistance and increased fluconazole/voriconazole MIC levels, were found to display alternative ways to resist azole drugs. Particularly, posaconazole/clotrimazole resistance after 31 days was correlated with increased expression of adhesin genes. This finding led us to identify the Epa3 adhesin as a new determinant of azole resistance. Besides being required for biofilm formation, Epa3 expression was found to decrease the intracellular accumulation of azole antifungal drugs. Altogether, this work provides a glimpse of the transcriptomics evolution of a C. glabrata population toward multiazole resistance, highlighting the multifactorial nature of the acquisition of azole resistance and pointing out a new player in azole resistance.
AB - Candida glabrata is an emerging fungal pathogen. Its increased prevalence is associated with its ability to rapidly develop antifungal drug resistance, particularly to azoles. In order to unravel new molecular mechanisms behind azole resistance, a transcriptomics analysis of the evolution of a C. glabrata clinical isolate (isolate 044) from azole susceptibility to posaconazole resistance (21st day), clotrimazole resistance (31st day), and fluconazole and voriconazole resistance (45th day), induced by longstanding incubation with fluconazole, was carried out. All the evolved strains were found to accumulate lower concentrations of azole drugs than the parental strain, while the ergosterol concentration remained mostly constant. However, only the population displaying resistance to all azoles was found to have a gain-of-function mutation in the C. glabrata PDR1 gene, leading to the upregulation of genes encoding multidrug resistance transporters. Intermediate strains, exhibiting posaconazole/clotrimazole resistance and increased fluconazole/voriconazole MIC levels, were found to display alternative ways to resist azole drugs. Particularly, posaconazole/clotrimazole resistance after 31 days was correlated with increased expression of adhesin genes. This finding led us to identify the Epa3 adhesin as a new determinant of azole resistance. Besides being required for biofilm formation, Epa3 expression was found to decrease the intracellular accumulation of azole antifungal drugs. Altogether, this work provides a glimpse of the transcriptomics evolution of a C. glabrata population toward multiazole resistance, highlighting the multifactorial nature of the acquisition of azole resistance and pointing out a new player in azole resistance.
KW - Azole drug resistance
KW - Candida glabrata
KW - Epa3
KW - Evolution
KW - Transcriptomics
UR - http://www.scopus.com/inward/record.url?scp=85058922924&partnerID=8YFLogxK
U2 - 10.1128/AAC.00995-18
DO - 10.1128/AAC.00995-18
M3 - Article
C2 - 30348666
AN - SCOPUS:85058922924
SN - 0066-4804
VL - 63
JO - Antimicrobial Agents and Chemotherapy
JF - Antimicrobial Agents and Chemotherapy
IS - 1
M1 - e00995-18
ER -
