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Hossain S, Lash E, Veri AO, Cowen LE. Functional connections between cell cycle and proteostasis in the regulation of Candida albicans morphogenesis. Cell Rep 2021; 34:108781. [PMID: 33626353 PMCID: PMC7971348 DOI: 10.1016/j.celrep.2021.108781] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/18/2020] [Accepted: 02/02/2021] [Indexed: 02/06/2023] Open
Abstract
Morphological plasticity is a key virulence trait for many fungal pathogens. For the opportunistic fungal pathogen Candida albicans, transitions among yeast, pseudohyphal, and hyphal forms are critical for virulence, because the morphotypes play distinct roles in the infection process. C. albicans morphogenesis is induced in response to many host-relevant conditions and is regulated by complex signaling pathways and cellular processes. Perturbation of either cell-cycle progression or protein homeostasis induces C. albicans filamentation, demonstrating that these processes play a key role in morphogenetic control. Regulators such as cyclin-dependent kinases, checkpoint proteins, the proteasome, the heat shock protein Hsp90, and the heat shock transcription factor Hsf1 all influence morphogenesis, often through interconnected effects on the cell cycle and proteostasis. This review highlights the major cell-cycle and proteostasis regulators that modulate morphogenesis and discusses how these two processes intersect to regulate this key virulence trait.
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Affiliation(s)
- Saif Hossain
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Emma Lash
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Amanda O Veri
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada.
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2
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Zhang C, Xue Q, Hou J, Mohsin A, Zhang M, Guo M, Zhu Y, Bao J, Wang J, Xiao W, Cao L. In-Depth Two-Stage Transcriptional Reprogramming and Evolutionary Engineering of Saccharomyces cerevisiae for Efficient Bioethanol Production from Xylose with Acetate. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:12002-12012. [PMID: 31595746 DOI: 10.1021/acs.jafc.9b05095] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In order to achieve rapid xylose utilization in the presence of acetate, improved yeast strains were engineered for higher bioethanol production. First, a six-gene cluster, including XYL1/XYL2/XKS1/TAL1/PYK1/MGT05196, was generated by using an in-depth two-stage (glucose and xylose) transcription reprogramming strategy in an evolutionary adapted strain of CE7, resulting in two improved engineered strains WXY46 and WXY53. Through a combined screening of xylose and glucose stage-specific promoters between tricarboxylic acid (TCA)/HSP and constitutive types, respectively, WXY46 with the constitutive promoters showed a much higher ethanol yield than that of WXY53 with the TCA/HSP promoters. Second, an optimized strain WXY74 was obtained by using more copies of a six-gene cluster, which resulted in a higher ethanol yield of 0.500 g/g total sugars with acetate conditions. At last, simultaneous saccharification and co-fermentation were performed by using the evolved WXY74 strain, which produced 58.4 g/L of ethanol from wheat straw waste and outperformed previous haploid XR-XDH strains.
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Affiliation(s)
- Cheng Zhang
- College of Life Sciences , Capital Normal University , Beijing 100048 , China
| | - Qian Xue
- College of Life Sciences , Capital Normal University , Beijing 100048 , China
| | - Junyan Hou
- College of Life Sciences , Capital Normal University , Beijing 100048 , China
| | - Ali Mohsin
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , Shanghai 200237 , China
| | - Mei Zhang
- College of Life Sciences , Capital Normal University , Beijing 100048 , China
| | - Meijin Guo
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , Shanghai 200237 , China
| | - Yixuan Zhu
- College of Life Sciences , Capital Normal University , Beijing 100048 , China
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , Shanghai 200237 , China
| | - Jingyu Wang
- Department of Chemical Engineering and Materials Science , University of Minnesota , Twin Cities, Minneapolis , Minnesota 55455 , United States
| | - Wei Xiao
- College of Life Sciences , Capital Normal University , Beijing 100048 , China
| | - Limin Cao
- College of Life Sciences , Capital Normal University , Beijing 100048 , China
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3
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Lindahl PA. A comprehensive mechanistic model of iron metabolism in Saccharomyces cerevisiae. Metallomics 2019; 11:1779-1799. [PMID: 31531508 DOI: 10.1039/c9mt00199a] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The ironome of budding yeast (circa 2019) consists of approximately 139 proteins and 5 nonproteinaceous species. These proteins were grouped according to location in the cell, type of iron center(s), and cellular function. The resulting 27 groups were used, along with an additional 13 nonprotein components, to develop a mesoscale mechanistic model that describes the import, trafficking, metallation, and regulation of iron within growing yeast cells. The model was designed to be simultaneously mutually autocatalytic and mutually autoinhibitory - a property called autocatinhibitory that should be most realistic for simulating cellular biochemical processes. The model was assessed at the systems' level. General conclusions are presented, including a new perspective on understanding regulatory mechanisms in cellular systems. Some unsettled issues are described. This model, once fully developed, has the potential to mimic the phenotype (at a coarse-grain level) of all iron-related genetic mutations in this simple and well-studied eukaryote.
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Affiliation(s)
- Paul A Lindahl
- Departments of Chemistry and of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-3255, USA.
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4
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Zhao ZS, Manser E. PAK family kinases: Physiological roles and regulation. CELLULAR LOGISTICS 2014; 2:59-68. [PMID: 23162738 PMCID: PMC3490964 DOI: 10.4161/cl.21912] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The p21-activated kinases (PAKs) are a family of Ser/Thr protein kinases that are represented by six genes in humans (PAK 1-6), and are found in all eukaryotes sequenced to date. Genetic and knockdown experiments in frogs, fish and mice indicate group I PAKs are widely expressed, required for multiple tissue development, and particularly important for immune and nervous system function in the adult. The group II PAKs (human PAKs 4-6) are more enigmatic, but their restriction to metazoans and presence at cell-cell junctions suggests these kinases emerged to regulate junctional signaling. Studies of protozoa and fungal PAKs show that they regulate cell shape and polarity through phosphorylation of multiple cytoskeletal proteins, including microtubule binding proteins, myosins and septins. This chapter discusses what we know about the regulation of PAKs and their physiological role in different model organisms, based primarily on gene knockout studies.
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Affiliation(s)
- Zhuo-Shen Zhao
- sGSK Group; Astar Neuroscience Research Partnership; Singapore
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Carlsson M, Gustavsson M, Hu GZ, Murén E, Ronne H. A Ham1p-dependent mechanism and modulation of the pyrimidine biosynthetic pathway can both confer resistance to 5-fluorouracil in yeast. PLoS One 2013; 8:e52094. [PMID: 24124444 PMCID: PMC3792807 DOI: 10.1371/journal.pone.0052094] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 11/09/2012] [Indexed: 12/13/2022] Open
Abstract
5-Fluorouracil (5-FU) is an anticancer drug and pyrimidine analogue. A problem in 5-FU therapy is acquired resistance to the drug. To find out more about the mechanisms of resistance, we screened a plasmid library in yeast for genes that confer 5-FU resistance when overexpressed. We cloned five genes: CPA1, CPA2, HMS1, HAM1 and YJL055W. CPA1 and CPA2 encode a carbamoyl phosphate synthase involved in arginine biosynthesis and HMS1 a helix-loop-helix transcription factor. Our results suggest that CPA1, CPA2, and HMS1 confer 5-FU resistance by stimulating pyrimidine biosynthesis. Thus, they are unable to confer 5-FU resistance in a ura2 mutant, and inhibit the uptake and incorporation into RNA of both uracil and 5-FU. In contrast, HAM1 and YJL055W confer 5-FU resistance in a ura2 mutant, and selectively inhibit incorporation into RNA of 5-FU but not uracil. HAM1 is the strongest resistance gene, but it partially depends on YJL055W for its function. This suggests that HAM1 and YJL055W function together in mediating resistance to 5-FU. Ham1p encodes an inosine triphosphate pyrophosphatase that has been implicated in resistance to purine analogues. Our results suggest that Ham1p could have a broader specificity that includes 5-FUTP and other pyrimidine analogoue triphosphates.
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Affiliation(s)
- Mattias Carlsson
- Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Marie Gustavsson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Guo-Zhen Hu
- Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Eva Murén
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Hans Ronne
- Department of Microbiology, Swedish University of Agricultural Sciences, Uppsala, Sweden
- * E-mail:
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Abstract
Temperature affects diverse biological processes. In fungi such as the pathogen Candida albicans, temperature governs a morphogenetic switch between yeast and hyphal growth. A new report connects the thermosensor Hsp90 to a CDK-cyclin-transcription factor module that controls morphogenesis.
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Affiliation(s)
- Wenjie Xu
- 200B Mellon Institute, Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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Shapiro RS, Sellam A, Tebbji F, Whiteway M, Nantel A, Cowen LE. Pho85, Pcl1, and Hms1 signaling governs Candida albicans morphogenesis induced by high temperature or Hsp90 compromise. Curr Biol 2012; 22:461-70. [PMID: 22365851 DOI: 10.1016/j.cub.2012.01.062] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 01/13/2012] [Accepted: 01/30/2012] [Indexed: 12/14/2022]
Abstract
BACKGROUND Temperature exerts powerful control over development and virulence of diverse pathogens. In the leading human fungal pathogen, Candida albicans, temperature governs morphogenesis, a key virulence trait. Many cues that induce the yeast to filament transition are contingent on a minimum of 37°C, whereas further elevation to 39°C serves as an independent inducer. The molecular chaperone Hsp90 is a key regulator of C. albicans temperature-dependent morphogenesis. Compromise of Hsp90 function genetically, pharmacologically, or by elevated temperature induces filamentation in a manner that depends on protein kinase A signaling but is independent of the terminal transcription factor, Efg1. RESULTS Here, we establish that despite morphological and regulatory differences, inhibition of Hsp90 induces a transcriptional profile similar to that induced by other filamentation cues and does so independently of Efg1. Further, we identify Hms1 as a transcriptional regulator required for morphogenesis induced by elevated temperature or Hsp90 compromise. Hms1 functions downstream of the cyclin Pcl1 and the cyclin-dependent kinase Pho85, both of which are required for temperature-dependent filamentation. Upon Hsp90 inhibition, Hms1 binds to DNA elements involved in filamentous growth, including UME6 and RBT5, and regulates their expression, providing a mechanism through which Pho85, Pcl1, and Hms1 govern morphogenesis. Consistent with the importance of morphogenetic flexibility for virulence, deletion of C. albicans HMS1 attenuates virulence in a metazoan model of infection. CONCLUSIONS Thus, we establish a new mechanism through which Hsp90 orchestrates C. albicans morphogenesis, and define novel regulatory circuitry governing a temperature-dependent developmental program, with broad implications for temperature sensing and virulence of microbial pathogens.
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Affiliation(s)
- Rebecca S Shapiro
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
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Lin M, Grillitsch K, Daum G, Just U, Höfken T. Modulation of sterol homeostasis by the Cdc42p effectors Cla4p and Ste20p in the yeast Saccharomyces cerevisiae. FEBS J 2010; 276:7253-64. [PMID: 20050180 DOI: 10.1111/j.1742-4658.2009.07433.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The conserved Rho-type GTPase Cdc42p is a key regulator of signal transduction and polarity in eukaryotic cells. In the yeast Saccharomyces cerevisiae, Cdc42p promotes polarized growth through the p21-activated kinases Ste20p and Cla4p. Previously, we demonstrated that Ste20p forms a complex with Erg4p, Cbr1p and Ncp1p, which all catalyze important steps in sterol biosynthesis. CLA4 interacts genetically with ERG4 and NCP1. Furthermore, Erg4p, Ncp1p and Cbr1p play important roles in cell polarization during vegetative growth, mating and filamentation. As Ste20p and Cla4p are involved in these processes it seems likely that sterol biosynthetic enzymes and p21-activated kinases act in related pathways. Here, we demonstrate that the deletion of either STE20 or CLA4 results in increased levels of sterols. In addition, higher concentrations of steryl esters, the storage form of sterols, were observed in cla4Delta cells. CLA4 expression from a multicopy plasmid reduces enzyme activity of Are2p, the major steryl ester synthase, under aerobic conditions. Altogether, our data suggest that Ste20p and Cla4p may function as negative modulators of sterol biosynthesis. Moreover, Cla4p has a negative effect on steryl ester formation. As sterol homeostasis is crucial for cell polarization, Ste20p and Cla4p may regulate cell polarity in part through the modulation of sterol homeostasis.
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Affiliation(s)
- Meng Lin
- Institute of Biochemistry, Christian Albrecht University, Kiel, Germany
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Kumar A, Molli PR, Pakala SB, Bui Nguyen TM, Rayala SK, Kumar R. PAK thread from amoeba to mammals. J Cell Biochem 2009; 107:579-85. [PMID: 19350548 DOI: 10.1002/jcb.22159] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The p21-activated kinases (PAKs) are signaling nodes that play a crucial role in cellular processes including cell motility, differentiation, survival, gene transcription, and hormone signaling. PAKs are highly conserved family of serine-threonine kinases that act as effector for small GTPases Rac and Cdc42. Most of our knowledge about PAK functions has been derived from genetic approaches in lower organisms and many of these functions are similar to that seen in mammalian cells. In this review, we have summarized the extensive information generated in lower eukaryotes and very briefly discussed the current status of PAKs in humans.
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Affiliation(s)
- Anupam Kumar
- Department of Biochemistry and Molecular Biology, George Washington University Medical Center, Washington, District of Columbia 20037, USA
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10
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Lin M, Unden H, Jacquier N, Schneiter R, Just U, Höfken T. The Cdc42 effectors Ste20, Cla4, and Skm1 down-regulate the expression of genes involved in sterol uptake by a mitogen-activated protein kinase-independent pathway. Mol Biol Cell 2009; 20:4826-37. [PMID: 19793923 DOI: 10.1091/mbc.e09-01-0034] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
In Saccharomyces cerevisiae, the Rho-type GTPase Cdc42 regulates polarized growth through its effectors, including the p21-activated kinases (PAKs) Ste20, Cla4, and Skm1. Previously, we demonstrated that Ste20 interacts with several proteins involved in sterol synthesis that are crucial for cell polarization. Under anaerobic conditions, sterols cannot be synthesized and need to be imported into cells. Here, we show that Ste20, Cla4, and Skm1 form a complex with Sut1, a transcriptional regulator that promotes sterol uptake. All three PAKs can translocate into the nucleus and down-regulate the expression of genes involved in sterol uptake, including the Sut1 targets AUS1 and DAN1 by a novel mechanism. Consistently, deletion of either STE20, CLA4, or SKM1 results in an increased sterol influx and PAK overexpression inhibits sterol uptake. For Ste20, we demonstrate that the down-regulation of gene expression requires nuclear localization and kinase activity of Ste20. Furthermore, the Ste20-mediated control of expression of sterol uptake genes depends on SUT1 but is independent of a mitogen-activated protein kinase signaling cascade. Together, these observations suggest that PAKs translocate into the nucleus, where they modulate expression of sterol uptake genes via Sut1, thereby controlling sterol homeostasis.
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Affiliation(s)
- Meng Lin
- Institute of Biochemistry, Christian Albrecht University, 24098 Kiel, Germany
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11
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Tiedje C, Holland DG, Just U, Höfken T. Proteins involved in sterol synthesis interact with Ste20 and regulate cell polarity. J Cell Sci 2007; 120:3613-24. [PMID: 17895367 DOI: 10.1242/jcs.009860] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The Saccharomyces cerevisiae p21-activated kinase (PAK) Ste20 regulates various aspects of cell polarity during vegetative growth, mating and filamentous growth. To gain further insight into the mechanisms of Ste20 action, we screened for interactors of Ste20 using the split-ubiquitin system. Among the identified proteins were Erg4, Cbr1 and Ncp1, which are all involved in sterol biosynthesis. The interaction between Ste20 and Erg4, as well as between Ste20 and Cbr1, was confirmed by pull-down experiments. Deletion of either ERG4 or NCP1 resulted in various polarity defects, indicating a role for these proteins in bud site selection, apical bud growth, cell wall assembly, mating and invasive growth. Interestingly, Erg4 was required for the polarized localization of Ste20 during mating. Lack of CBR1 produced no detectable phenotype, whereas the deletion of CBR1 in the absence of NCP1 was lethal. Using a conditional lethal mutant we demonstrate that both proteins have overlapping functions in bud morphology.
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Affiliation(s)
- Christopher Tiedje
- Institute of Biochemistry, Christian Albrecht University Kiel, Olshausenstrasse 40, 24098 Kiel, Germany.
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12
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Lahmy S, Guilleminot J, Schmit AC, Pelletier G, Chaboute ME, Devic M. QQT proteins colocalize with microtubules and are essential for early embryo development in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2007; 50:615-26. [PMID: 17419841 DOI: 10.1111/j.1365-313x.2007.03072.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
During Arabidopsis embryogenesis, the control of division between daughter cells is critical for pattern formation. Two embryo-defective (emb) mutant lines named quatre-quart (qqt) were characterized by forward and reverse genetics. The terminal arrest of qqt1 and qqt2 embryos was at the octant stage, just prior to the round of periclinal divisions that establishes the dermatogen stage . Homozygous embryos of a weaker allele of qqt1 were able to divide further, resulting in aberrant periclinal divisions. These phenotypic analyses support an essential role of the QQT proteins in the correct formation of the tangential divisions. That an important proportion of qqt1 embryos were arrested prior to the octant stage indicated a more general role in cell division. The analysis of QQT1 and QQT2 genes revealed that they belong to a small subgroup of the large family encoding ATP/GTP binding proteins, and are widely conserved among plants, vertebrates and Archaea. We showed that QQT1 and QQT2 proteins interact with each other in a yeast two-hybrid system, and that QQT1 and QQT2 tagged by distinct fluorescent probes colocalize with microtubules during mitosis, in agreement with their potential role in cell division and their mutant phenotype. We propose that QQT1 and QQT2 proteins participate in the organization of microtubules during cell division, and that this function is essential for the correct development of the early embryo.
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Affiliation(s)
- Sylvie Lahmy
- Laboratoire Génome et Développement des Plantes, UMRCNRS 5096, Université de Perpignan, Avenue Paul Alduy, 66860 Perpignan-cedex, France
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Miyakawa Y, Chibana H, Uno J, Mikami Y, Nakayama H. [Essential genes as potential targets of antifungal agents in pathogenic yeast Candida]. ACTA ACUST UNITED AC 2007; 47:269-74. [PMID: 17086158 DOI: 10.3314/jjmm.47.269] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
An important point in the development of an antimicrobial agent is whether its target molecules are essential for growth of the microorganism. From this viewpoint, we focused attention on essential genes as potential targets of antifungal agents in the pathogenic yeast Candida. Here we introduce recent attempts for screening, identification, and characterization of essential genes from a haploid yeast Candida glabrata, using temperature-sensitive mutants. Our experimental results suggesting the essentiality of C. albicans PHO85, the homologue of which is known as a negative regulator of the PHO system and as a non-essential gene in Saccharomyces cerevisiae are also described.
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Affiliation(s)
- Yozo Miyakawa
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Japan
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Gildor T, Shemer R, Atir-Lande A, Kornitzer D. Coevolution of cyclin Pcl5 and its substrate Gcn4. EUKARYOTIC CELL 2005; 4:310-8. [PMID: 15701793 PMCID: PMC549342 DOI: 10.1128/ec.4.2.310-318.2005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Gcn4, a transcription factor that plays a key role in the response of Saccharomyces cerevisiae to amino acid starvation, is regulated at both the levels of translation and of protein stability. Regulated degradation of Gcn4 depends on its phosphorylation by the cyclin-dependent kinase Pho85, in conjunction with the cyclin Pcl5. The pathogenic yeast Candida albicans contains a functional homolog of Gcn4, which is involved in amino acid metabolism, as well as in the regulation of filamentous growth in response to starvation. Here, we show that C. albicans Gcn4 (CaGcn4) is rapidly degraded and that this degradation depends on a Pho85 cyclin homolog, CaPcl5. The regulatory loop that includes Gcn4 and Pcl5 is conserved in C. albicans: like in S. cerevisiae, CaPcl5 is transcriptionally induced by CaGcn4 and is required for CaGcn4 degradation. However, the proteins have coevolved so that there is no cross-recognition between the proteins from the two species: phosphorylation-dependent degradation of CaGcn4 occurs only in the presence of CaPcl5, and S. cerevisiae Gcn4 (ScGcn4) requires ScPcl5 for its degradation. Phenotypic analysis of the Capcl5 mutant indicates that CaPcl5 also modulates the filamentous response of C. albicans in amino acid-rich media.
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Affiliation(s)
- Tsvia Gildor
- Department of Molecular Microbiology, B. Rappaport Faculty of Medicine, Technion-IIT, Rappaport Institute for Research in the Medical Sciences, Haifa, 31096, Israel
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