PKC signaling regulates drug resistance of the fungal pathogen Candida albicans via circuitry comprised of Mkc1, calcineurin, and Hsp90.
PKC signaling regulates drug resistance of the fungal pathogen Candida albicans via circuitry comprised of Mkc1, calcineurin, and Hsp90.
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DOI：
10.1371/journal.ppat.1001069
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发表时间：
2010-08-26
期刊：
影响因子：
6.7
通讯作者：
Cowen LE
中科院分区：
文献类型：
--
作者：
LaFayette SL;Collins C;Zaas AK;Schell WA;Betancourt-Quiroz M;Gunatilaka AA;Perfect JR;Cowen LE
真菌病原体利用不同的机制在暴露于抗真菌药物后存活。考虑到临床上有用的抗真菌药物数量有限，以及免疫功能低下的个体容易受到危及生命的真菌感染的人口不断增长，这引起了人们的关注。为了识别消除对最广泛使用的抗真菌药物（唑类）耐药性的分子，我们对1，280种药理活性化合物进行了筛选。取消唑类耐药突变体的模型酵母酿酒酵母和临床分离的主要人类真菌病原体白色念珠菌的7个命中中的3个是蛋白激酶C（PKC）的抑制剂，其调节生长、形态发生和对细胞壁应激的响应期间的细胞壁完整性。Pkc 1的药理学或遗传损伤赋予对多种靶向关键细胞膜固醇麦角固醇合成的药物的超敏反应，包括唑类、烯丙胺类和吗啉类。PKC 1使细胞膜应激的生存至少部分通过有丝分裂原活化蛋白激酶（MAPK）级联反应，在这两个物种，但通过不同的下游效应。引人注目的是，抑制Pkc 1表型模仿抑制分子伴侣Hsp 90或其客户蛋白钙调磷酸酶。PKC信号是激活钙调磷酸酶所必需的。啤酒。相反，Pkc 1和钙调神经磷酸酶通过共同的靶点独立调节C.白色念珠菌。我们在C中确定了一个额外的监管控制级别。白色念珠菌连接PKC信号传导，Hsp 90，和钙调神经磷酸酶的Hsp 90的遗传减少导致终端MAPK，Mkc 1的耗尽电路。删除C。在系统性念珠菌病的小鼠模型中，白念珠菌PKC 1使真菌抑制性麦角固醇生物合成抑制剂具有杀真菌和减弱的毒力。这项工作确立了PKC信号传导在耐药性中的新作用，Hsp 90通过其调节耐药性的新电路，并且靶向应激反应信号传导为治疗危及生命的真菌感染提供了有希望的策略。由于耐药性的出现和临床上有用的抗真菌药物数量有限，治疗真菌感染具有挑战性。我们筛选了一个包含1,280种抗真菌活性化合物的库，以确定那些能够逆转主要人类真菌病原体白色念珠菌对最广泛使用的抗真菌药物唑类药物的耐药性的化合物。这揭示了蛋白激酶C（PKC）信号传导在对靶向细胞膜的药物（包括唑类、烯丙胺类和吗啉类）的抗性中的新作用。我们剖析了PKC调节C.白色念珠菌和模式酵母酿酒酵母。在这两个物种中，PKC至少部分通过丝裂原活化蛋白激酶（MAPK）级联反应使细胞膜应激存活。In S.在酿酒酵母中，抑制PKC信号传导阻断了膜应激反应的关键调节因子钙调神经磷酸酶的激活。In C.白念珠菌、Pkc 1和钙调神经磷酸酶通过共同的靶点独立地调节抗性。删除C。在小鼠模型中，白念珠菌PKC 1使抑真菌药物具有杀真菌作用并降低毒力。分子伴侣Hsp 90稳定了客户蛋白，包括钙调磷酸酶，也稳定了末端C。白念珠菌MAPK，Mkc 1.我们建立了连接PKC与Hsp 90和钙调神经磷酸酶的新回路，并提出了一种治疗危及生命的真菌感染的有前途的策略。
Fungal pathogens exploit diverse mechanisms to survive exposure to antifungal drugs. This poses concern given the limited number of clinically useful antifungals and the growing population of immunocompromised individuals vulnerable to life-threatening fungal infection. To identify molecules that abrogate resistance to the most widely deployed class of antifungals, the azoles, we conducted a screen of 1,280 pharmacologically active compounds. Three out of seven hits that abolished azole resistance of a resistant mutant of the model yeast Saccharomyces cerevisiae and a clinical isolate of the leading human fungal pathogen Candida albicans were inhibitors of protein kinase C (PKC), which regulates cell wall integrity during growth, morphogenesis, and response to cell wall stress. Pharmacological or genetic impairment of Pkc1 conferred hypersensitivity to multiple drugs that target synthesis of the key cell membrane sterol ergosterol, including azoles, allylamines, and morpholines. Pkc1 enabled survival of cell membrane stress at least in part via the mitogen activated protein kinase (MAPK) cascade in both species, though through distinct downstream effectors. Strikingly, inhibition of Pkc1 phenocopied inhibition of the molecular chaperone Hsp90 or its client protein calcineurin. PKC signaling was required for calcineurin activation in response to drug exposure in S. cerevisiae. In contrast, Pkc1 and calcineurin independently regulate drug resistance via a common target in C. albicans. We identified an additional level of regulatory control in the C. albicans circuitry linking PKC signaling, Hsp90, and calcineurin as genetic reduction of Hsp90 led to depletion of the terminal MAPK, Mkc1. Deletion of C. albicans PKC1 rendered fungistatic ergosterol biosynthesis inhibitors fungicidal and attenuated virulence in a murine model of systemic candidiasis. This work establishes a new role for PKC signaling in drug resistance, novel circuitry through which Hsp90 regulates drug resistance, and that targeting stress response signaling provides a promising strategy for treating life-threatening fungal infections. Treating fungal infections is challenging due to the emergence of drug resistance and the limited number of clinically useful antifungal drugs. We screened a library of 1,280 pharmacologically active compounds to identify those that reverse resistance of the leading human fungal pathogen, Candida albicans, to the most widely used antifungals, the azoles. This revealed a new role for protein kinase C (PKC) signaling in resistance to drugs targeting the cell membrane, including azoles, allylamines, and morpholines. We dissected mechanisms through which PKC regulates resistance in C. albicans and the model yeast Saccharomyces cerevisiae. PKC enabled survival of cell membrane stress at least in part through the mitogen-activated protein kinase (MAPK) cascade in both species. In S. cerevisiae, inhibition of PKC signaling blocked activation of a key regulator of membrane stress responses, calcineurin. In C. albicans, Pkc1 and calcineurin independently regulate resistance via a common target. Deletion of C. albicans PKC1 rendered fungistatic drugs fungicidal and reduced virulence in a mouse model. The molecular chaperone Hsp90, which stabilizes client proteins including calcineurin, also stabilized the terminal C. albicans MAPK, Mkc1. We establish new circuitry connecting PKC with Hsp90 and calcineurin and suggest a promising strategy for treating life-threatening fungal infections.
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影响因子：
6.7
作者：
Blankenship JR;Fanning S;Hamaker JJ;Mitchell AP
通讯作者：
Mitchell AP
DOI：
10.1016/0006-291x(90)91544-3
发表时间：
1990-11-15
影响因子：
3.1
作者：
HERBERT, JM;AUGEREAU, JM;MAFFRAND, JP
通讯作者：
MAFFRAND, JP
DOI：
10.1016/j.bbapap.2005.07.032
发表时间：
2005-12-30
影响因子：
3.2
作者：
Heinisch, JJ
通讯作者：
Heinisch, JJ
DOI：
10.1073/pnas.90.24.11558
发表时间：
1993-12-15
影响因子：
11.1
作者：
BALDAUF, SL;PALMER, JD
通讯作者：
PALMER, JD
影响因子：
6.7
作者：
Cowen LE
通讯作者：
Cowen LE