scholarly journals Yap5 Competes With Hap4 for the Regulation of Iron Homeostasis Genes in the Human Pathogen Candida glabrata

Author(s):  
Thierry Delaveau ◽  
Antonin Thiébaut ◽  
Médine Benchouaia ◽  
Jawad Merhej ◽  
Frédéric Devaux

The CCAAT-binding complex (CBC) is a conserved heterotrimeric transcription factor which, in fungi, requires additional regulatory subunits to act on transcription. In the pathogenic yeast Candida glabrata, CBC has a dual role. Together with the Hap4 regulatory subunit, it activates the expression of genes involved in respiration upon growth with non-fermentable carbon sources, while its association with the Yap5 regulatory subunit is required for the activation of iron tolerance genes in response to iron excess. In the present work, we investigated further the interplay between CBC, Hap4 and Yap5. We showed that Yap5 regulation requires a specific Yap Response Element in the promoter of its target gene GRX4 and that the presence of Yap5 considerably strengthens the binding of CBC to the promoters of iron tolerance genes. Chromatin immunoprecipitation (ChIP) and transcriptome experiments showed that Hap4 can also bind these promoters but has no impact on the expression of those genes when Yap5 is present. In the absence of Yap5 however, GRX4 is constitutively regulated by Hap4, similarly to the genes involved in respiration. Our results suggest that the distinction between the two types of CBC targets in C. glabrata is mainly due to the dependency of Yap5 for very specific DNA sequences and to the competition between Hap4 and Yap5 at the promoter of the iron tolerance genes.

1987 ◽  
Vol 7 (4) ◽  
pp. 1371-1377 ◽  
Author(s):  
T Toda ◽  
S Cameron ◽  
P Sass ◽  
M Zoller ◽  
J D Scott ◽  
...  

We have cloned a gene (BCY1) from the yeast Saccharomyces cerevisiae that encodes a regulatory subunit of the cyclic AMP-dependent protein kinase. The encoded protein has a structural organization similar to that of the RI and RII regulatory subunits of the mammalian cyclic AMP-dependent protein kinase. Strains of S. cerevisiae with disrupted BCY1 genes do not display a cyclic AMP-dependent protein kinase in vitro, fail to grow on many carbon sources, and are exquisitely sensitive to heat shock and starvation.


2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Thomas Denecker ◽  
Youfang Zhou Li ◽  
Cécile Fairhead ◽  
Karine Budin ◽  
Jean-Michel Camadro ◽  
...  

Abstract Candida glabrata is a cause of life-threatening invasive infections especially in elderly and immunocompromised patients. Part of human digestive and urogenital microbiota, C. glabrata faces varying iron availability, low during infection or high in digestive and urogenital tracts. To maintain its homeostasis, C. glabrata must get enough iron for essential cellular processes and resist toxic iron excess. The response of this pathogen to both depletion and lethal excess of iron at 30°C have been described in the literature using different strains and iron sources. However, adaptation to iron variations at 37°C, the human body temperature and to gentle overload, is poorly known. In this study, we performed transcriptomic experiments at 30°C and 37°C with low and high but sub-lethal ferrous concentrations. We identified iron responsive genes and clarified the potential effect of temperature on iron homeostasis. Our exploration of the datasets was facilitated by the inference of functional networks of co-expressed genes, which can be accessed through a web interface. Relying on stringent selection and independently of existing knowledge, we characterized a list of 214 genes as key elements of C. glabrata iron homeostasis and interesting candidates for medical applications.


2004 ◽  
Vol 3 (5) ◽  
pp. 1154-1163 ◽  
Author(s):  
Tanja Stoyan ◽  
John Carbon

ABSTRACT The human pathogenic yeast Candida glabrata is the second most common Candida pathogen after Candida albicans, causing both bloodstream and mucosal infections. The centromere (CEN) DNA of C. glabrata (CgCEN), although structurally very similar to that of Saccharomyces cerevisiae, is not functional in S. cerevisiae. To further examine the structure of the C. glabrata inner kinetochore, we isolated several C. glabrata homologs of S. cerevisiae inner kinetochore protein genes, namely, genes for components of the CBF3 complex (Ndc10p, Cep3p, and Ctf13p) and genes for the proteins Mif2p and Cse4p. The amino acid sequence identities of these proteins were 32 to 49% relative to S. cerevisiae. CgNDC10, CgCEP3, and CgCTF13 are required for growth in C. glabrata and are specifically found at CgCEN, as demonstrated by chromatin immunoprecipitation experiments. Cross-complementation experiments revealed that the isolated genes, with the exception of CgCSE4, are species specific and cannot functionally substitute for the corresponding genes in S. cerevisiae deletion strains. Likewise, the S. cerevisiae CBF3 genes NDC10, CEP3, and CTF13 cannot functionally replace their homologs in C. glabrata CBF3 deletion strains. Two-hybrid analysis revealed several interactions between these proteins, all of which were previously reported for the inner kinetochore proteins of S. cerevisiae. Our findings indicate that although many of the inner kinetochore components have evolved considerably between the two closely related species, the organization of the C. glabrata inner kinetochore is similar to that in S. cerevisiae.


1987 ◽  
Vol 7 (4) ◽  
pp. 1371-1377 ◽  
Author(s):  
T Toda ◽  
S Cameron ◽  
P Sass ◽  
M Zoller ◽  
J D Scott ◽  
...  

We have cloned a gene (BCY1) from the yeast Saccharomyces cerevisiae that encodes a regulatory subunit of the cyclic AMP-dependent protein kinase. The encoded protein has a structural organization similar to that of the RI and RII regulatory subunits of the mammalian cyclic AMP-dependent protein kinase. Strains of S. cerevisiae with disrupted BCY1 genes do not display a cyclic AMP-dependent protein kinase in vitro, fail to grow on many carbon sources, and are exquisitely sensitive to heat shock and starvation.


Author(s):  
Lumin Wei ◽  
Rongjing Zhang ◽  
Jinzhao Zhang ◽  
Juanjuan Li ◽  
Deping Kong ◽  
...  

AbstractProtein kinase A (PKA) plays an important role in regulating inflammation via its catalytic subunits. Recently, PKA regulatory subunits have been reported to directly modulate some signaling pathways and alleviate inflammation. However, the role of PKA regulatory subunits in colonic inflammation remains unclear. Therefore, we conducted this study to investigate the role of the PKA regulatory subunit PRKAR2A in colitis. We observed that PRKAR2A deficiency protected mice from dextran sulfate sodium (DSS)-induced experimental colitis. Our experiments revealed that the intestinal epithelial cell-specific deletion of Prkar2a contributed to this protection. Mechanistically, the loss of PRKAR2A in Prkar2a−/− mice resulted in an increased IFN-stimulated gene (ISG) expression and altered gut microbiota. Inhibition of ISGs partially reversed the protective effects against DSS-induced colitis in Prkar2a−/− mice. Antibiotic treatment and cross-fostering experiments demonstrated that the protection against DSS-induced colitis in Prkar2a−/− mice was largely dependent on the gut microflora. Altogether, our work demonstrates a previously unidentified function of PRKAR2A in promoting DSS-induced colitis.


Author(s):  
Yunfan Fan ◽  
Andrew N Gale ◽  
Anna Bailey ◽  
Kali Barnes ◽  
Kiersten Colotti ◽  
...  

Abstract We present a highly contiguous genome and transcriptome of the pathogenic yeast, Candida nivariensis. We sequenced both the DNA and RNA of this species using both the Oxford Nanopore Technologies (ONT) and Illumina platforms. We assembled the genome into an 11.8 Mb draft composed of 16 contigs with an N50 of 886 Kb, including a circular mitochondrial sequence of 28 Kb. Using direct RNA nanopore sequencing and Illumina cDNA sequencing, we constructed an annotation of our new assembly, supplemented by lifting over genes from Saccharomyces cerevisiae and Candida glabrata.


2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Daniel P Harris

TNF-α initiates the expression of genes involved in the recruitment, adhesion, and transmigration of leukocytes to sites of inflammation. Here, we report that the protein arginine methyltransferase PRMT5 is required for the transcriptional induction of the pro-inflammatory chemokine CXCL10 (IP-10) in endothelial cells. Depletion of PRMT5 by siRNA results in significantly diminished TNF-α-induced CXCL10 mRNA expression, but does not affect expression of other chemokines, such as MCP-1 or IL-8. Chromatin immunoprecipitation experiments of the CXCL10 proximal promoter show the presence of symmetrical dimethylated arginine (sDMA)-containing proteins upon exposure to TNF-α. This methylation is completely lost when PRMT5 is removed from cells by siRNA. Using immunoprecipitation, we show that PRMT5 enhances CXCL10 expression by methylating the RelA (p65) subunit of NF-κB. In summary, we have identified that PRMT5 is a novel regulator of CXCL10 expression. Further, we have discovered that PRMT5 methylates NF-κB, a finding which may further knowledge of the post-translational code governing NF-κB regulation and target specificity.


Author(s):  
Xiaomin Shang ◽  
Changhong Wang ◽  
Li Shen ◽  
Fei Sheng ◽  
Xiaohui He ◽  
...  

Plasmodium falciparum undergoes a series of asexual replications in human erythrocytes after infection, which are effective targets for combatting malaria. Here, we report roles of an ApiAP2 transcription factor PfAP2-EXP2 (PF3D7_0611200) in the intraerythrocytic developmental cycle of P. falciparum. PfAP2-EXP2 conditional knockdown resulted in an asexual growth defect but without an appreciable effect on parasite morphology. Further ChIP-seq analysis revealed that PfAP2-EXP2 targeted genes related to virulence and interaction between erythrocytes and parasites. Especially, PfAP2-EXP2 regulation of euchromatic genes does not depend on recognizing specific DNA sequences, while a CCCTAAACCC motif is found in its heterochromatic binding sites. Combined with transcriptome profiling, we suggest that PfAP2-EXP2 is participated in the intraerythrocytic development by affecting the expression of genes related to cell remodeling at the schizont stage. In summary, this study explores an ApiAP2 member plays an important role for the P. falciparum blood-stage replication, which suggests a new perspective for malaria elimination.


mSphere ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Siobhan A. Turner ◽  
Qinxi Ma ◽  
Mihaela Ola ◽  
Kontxi Martinez de San Vicente ◽  
Geraldine Butler

ABSTRACTFungi can use a wide variety of nitrogen sources. In the absence of preferred sources such as ammonium, glutamate, and glutamine, secondary sources, including most other amino acids, are used. Expression of the nitrogen utilization pathways is very strongly controlled at the transcriptional level. Here, we investigated the regulation of nitrogen utilization in the pathogenic yeastCandida parapsilosis. We found that the functions of many regulators are conserved with respect toSaccharomyces cerevisiaeand other fungi. For example, the core GATA activatorsGAT1andGLN3have a conserved role innitrogencataboliterepression (NCR). There is one ortholog ofGZF3andDAL80, which represses expression of genes in preferred nitrogen sources. The regulatorsPUT3andUGA3are required for metabolism of proline and γ-aminobutyric acid (GABA), respectively. However, the role of the Dal81 transcription factor is distinctly different. InS. cerevisiae, Dal81 is a positive regulator of acquisition of nitrogen from GABA, allantoin, urea, and leucine, and it is required for maximal induction of expression of the relevant pathway genes. InC. parapsilosis, induction of GABA genes is independent of Dal81, and deletingDAL81has no effect on acquisition of nitrogen from GABA or allantoin. Instead, Dal81 represses arginine synthesis during growth under preferred nitrogen conditions.IMPORTANCEUtilization of nitrogen by fungi is controlled bynitrogencataboliterepression (NCR). Expression of many genes is switched off during growth on nonpreferred nitrogen sources. Gene expression is regulated through a combination of activation and repression. Nitrogen regulation has been studied best in the model yeastSaccharomyces cerevisiae. We found that although many nitrogen regulators have a conserved function inSaccharomycesspecies, some do not. The Dal81 transcriptional regulator has distinctly different functions inS. cerevisiaeandC. parapsilosis. In the former, it regulates utilization of nitrogen from GABA and allantoin, whereas in the latter, it regulates expression of arginine synthesis genes. Our findings make an important contribution to our understanding of nitrogen regulation in a human-pathogenic fungus.


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