Redefining pleiotropic drug resistance in a pathogenic yeast: Pdr1 functions as a sensor of cellular stresses in Candida glabrata.
Redefining pleiotropic drug resistance in a pathogenic yeast: Pdr1 functions as a sensor of cellular stresses in Candida glabrata.
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光滑念珠菌是一种重要的人类机会性真菌病原体。光滑念珠菌感染的增加归因于对抗真菌药物的先天和获得性耐药。先前的研究表明，转录因子Pdr1和几个编码ABC转运蛋白的靶基因是对抗唑类和其他抗真菌药物的多效性防御的关键元件。这项研究利用Hermes转座子插入图谱来研究改变一线抗真菌药物氟康唑敏感性的Pdr1非依赖和Pdr1依赖机制。发现了几个不依赖Pdr1改变氟康唑敏感性的新基因(CYB5、SSK1、SSK2、HOG1、TRP1)。线粒体功能的bZIP转录抑制因子(CIN5)正调控Pdr1，而数百个编码线粒体蛋白的基因被证实为Pdr1的负调控基因。抗生素寡霉素激活Pdr1并拮抗氟康唑的药效可能是通过干扰光肩星天牛的线粒体突起。出乎意料的是，许多60S核糖体蛋白的破坏也激活了Pdr1，从而模仿了mRNA翻译抑制剂的效果。放线菌酮未能完全激活抗放线菌素Rpl28-Q38E突变体中的Pdr1。同样，氟康唑未能完全激活表达Erg11低亲和力变体的菌株中的Pdr1。氟康唑以非常缓慢的动力学激活Pdr1，这与细胞应激的延迟开始有关。这些发现与Pdr1直接感知外源物质的想法不一致，并支持另一种假说，即Pdr1感知只有在外源物质与其靶标接触后才产生的细胞压力。光滑念珠菌是一种机会性致病酵母菌，可引起不适和死亡。它的发病率一直在增加，因为我们常见的抗真菌药物具有天然的抵抗力。这项研究探索了整个基因组对氟康唑耐药性的影响。我们发现了几个新的和意想不到的基因可以影响对氟康唑的敏感性。几种抗生素也会改变氟康唑的疗效。最重要的是，我们发现Pdr1--氟康唑耐药的关键决定因素--不是通过与氟康唑的结合直接调节的，而是通过感知氟康唑阻断类固醇生物合成所引起的细胞压力来间接调节的。这种对耐药机制的新认识可以改善现有抗真菌药物的疗效，加速新疗法的开发。
Candida glabrata is a prominent opportunistic fungal pathogen of humans. The increasing incidence of C. glabrata infections is attributed to both innate and acquired resistance to antifungals. Previous studies suggest the transcription factor Pdr1 and several target genes encoding ABC transporters are critical elements of pleiotropic defense against azoles and other antifungals. This study utilizes Hermes transposon insertion profiling to investigate Pdr1-independent and Pdr1-dependent mechanisms that alter susceptibility to the frontline antifungal fluconazole. Several new genes were found to alter fluconazole susceptibility independent of Pdr1 (CYB5, SSK1, SSK2, HOG1, TRP1). A bZIP transcription repressor of mitochondrial function (CIN5) positively regulated Pdr1 while hundreds of genes encoding mitochondrial proteins were confirmed as negative regulators of Pdr1. The antibiotic oligomycin activated Pdr1 and antagonized fluconazole efficacy likely by interfering with mitochondrial processes in C. glabrata. Unexpectedly, disruption of many 60S ribosomal proteins also activated Pdr1, thus mimicking the effects of the mRNA translation inhibitors. Cycloheximide failed to fully activate Pdr1 in a cycloheximide-resistant Rpl28-Q38E mutant. Similarly, fluconazole failed to fully activate Pdr1 in a strain expressing a low-affinity variant of Erg11. Fluconazole activated Pdr1 with very slow kinetics that correlated with the delayed onset of cellular stress. These findings are inconsistent with the idea that Pdr1 directly senses xenobiotics and support an alternative hypothesis where Pdr1 senses cellular stresses that arise only after engagement of xenobiotics with their targets. Candida glabrata is an opportunistic pathogenic yeast that causes discomfort and death. Its incidence has been increasing because of natural defenses to our common antifungal medications. This study explores the entire genome for impacts on resistance to fluconazole. We find several new and unexpected genes can impact susceptibility to fluconazole. Several antibiotics can also alter the efficacy of fluconazole. Most importantly, we find that Pdr1—a key determinant of fluconazole resistance—is not regulated directly through binding of fluconazole and instead is regulated indirectly by sensing the cellular stresses caused by fluconazole blockage of sterol biosynthesis. This new understanding of drug resistance mechanisms could improve the outcomes of current antifungals and accelerate the development of novel therapeutics.
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DOI：
10.1016/j.cub.2021.09.084
发表时间：
2021-12-06
期刊：
Current biology : CB
影响因子：
--
作者：
Ksiezopolska E;Schikora-Tamarit MÀ;Beyer R;Nunez-Rodriguez JC;Schüller C;Gabaldón T
通讯作者：
Gabaldón T
影响因子：
3.5
作者：
KITADA, K;YAMAGUCHI, E;ARISAWA, M
通讯作者：
ARISAWA, M
影响因子：
3.7
作者：
Hanlon SE;Rizzo JM;Tatomer DC;Lieb JD;Buck MJ
通讯作者：
Buck MJ
影响因子：
64.5
作者：
Guydosh NR;Green R
通讯作者：
Green R
影响因子：
5.6
作者：
Hansen, JL;Moore, PB;Steitz, TA
通讯作者：
Steitz, TA