CSU52, a novel regulator functions as a repressor of L-sorbose utilization in Candida albicans

Background and Objectives: Monosomy of chromosome 5 associated with utilization of non-canonical sugar L-sorbose is one of the well-studied aneuploidies in Candida albicans. Stress-induced ploidy changes are crucial determinants for patho- genicity and genetic diversity in C. albicans. The five scattered regulatory regions (A, B, C, 135, and 139) comprising of two functionally redundant pathways (SUR1 and SUR2) were found to be responsible for the growth on L-sorbose. So far, three genes such as CSU51, CSU53 and CSU57 have been identified in region A, region 135 and region C, respectively. In this study we have verified the role of region B in this regulatory pathway. Materials and Methods: We employed a combinatorial gene deletion approach to verify the role of region B followed by co-over expression studies and qRT-PCR to identify the regulatory role of this region. Results: We confirmed the role of region B in the regulation of SOU1 gene expression. The qRT-PCR results showed that regulation occurs at transcriptional level along with other two regions in SUR1 pathway. A previously uncharacterized open reading frame in region B has been implicated in this regulation and designated as CSU52. Integrating multiple copies of CSU52 in the genome at tandem, suppresses the growth of recipient strain on L-sorbose, establishing it as a repressor of SOU1 gene. Conclusion: This finding completes the identification of regulators in SUR1 pathway. This result paves the way to study the underlying molecular mechanisms of SOU1 gene regulation that in-turn helps to understand stress induced aneuploidy.

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Ras1 involved in the antifungal resistance of Candida albicans and the inhibition of farnesol on the resistance of biofilms

10.21203/rs.2.13264/v1 ◽

2019 ◽

Author(s):

Xin Wei ◽

Lulu Zuo ◽

Shengyan Chen ◽

Zhenzhen Zhang ◽

Liuliu Jiang

Keyword(s):

Candida Albicans ◽

Molecular Mechanisms ◽

Hyphal Growth ◽

Antifungal Resistance ◽

Morphological Observation ◽

Inhibitory Effects ◽

Wild Strains ◽

Almost All ◽

Candida Albicans Biofilms

Abstract Background: Farnesol enhances the susceptibility of Candida albicans biofilms to antifungals, while the molecular mechanisms of this behavior are poorly understood. RAS1 regulates the hyphal growth of C. albicans, and farnesol inhibited hyphal growth by RAS1 regulation, while the role of RAS1 in the resistance of C. albicans biofilms and the molecular mechanism of the RAS1 in the farnesol-relevant antifungal capacity to C. albicans biofilms is still unknown. The study hypothesized that Ras1 involved in the antifungal resistance of C. albicans and the inhibition of farnesol on the resistance of biofilms. Results: The susceptibility assays showed that RAS1 over-expressing strain (RAS1OE) increased the resistance of C.albicans in both planktonic and biofilm form to antifungals, while RAS1 deletion strain (ras1Δ/Δ) reduced that to antifungals. The SMIC50 of the antifungals were increased with the mature of the biofilms formed from the mutant and the wild strains. Exogenous farnesol decreased the resistance of RAS1OE to antifungals, including fluconazole, amphotericin B, itraconazole, caspofungin, terbinafine, 5-flurocytosine and nystatin. The inhibitory effects of farnesol on the antifungal resistance of the biofilms from the RAS1OE were in accordance to almost all of the growth phases. Moreover, exogenous farnesol decreased the resistance of biofilms from RAS1OE more obviously than that from the wild strains (P<0.05). In addition, Morphological observation showed that that RAS1OE increased hyphal growth the biofilms, while ras1Δ/Δ reduced that of the biofilms. Compare to the wild-type strain, the inhibitory effects of farnesol on hyphal growth were more obvious to the RAS1OE, while less obvious to the ras1Δ/Δ. Furthermore, farnesol reduced the level of Ras1 and the expression of RAS1 of the biofilms formed from the RAS1OE strain compared with those of the untreated controls at all studied phases. Moreover, farnesol reduced the level of Ras1 and the expression of RAS1 of the biofilms formed from RAS1OE more obviously than that from the wild strains. Conclusions: Ras1 involved in the antifungal resistance of Candida albicans, and the inhibition of farnesol on the resistance of biofilm.

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Filamentation in Candida albicans is modulated by adaptive translation of farnesol signalling genes

10.1101/2021.01.20.427544 ◽

2021 ◽

Author(s):

Carla Oliveira ◽

Ana Rita Guimarães ◽

Inês Correia ◽

Inês Sousa ◽

Ana Poim ◽

...

Keyword(s):

Candida Albicans ◽

Molecular Mechanisms ◽

Phenotypic Diversity ◽

Critical Role ◽

Normal Growth ◽

Morphological Diversity ◽

Growth Conditions ◽

Response To Stress ◽

Variable Morphology

AbstractThe complex biology of the human pathogen Candida albicans is reflected in its remarkable ability to proliferate in numerous body sites, adapt to drastic changes in the environment, form various types of colonies and grow in yeast, pseudo-hyphal and hyphal forms. Much has been learnt in recent years about the relevance of this phenotypic plasticity, but the mechanisms that support it are still not fully understood. We have demonstrated that atypical translation of the CUG codon is a source of unexpected morphological diversity. The CUG codon is translated as both leucine (Leu) (~3%) and serine (Ser) (~97%) in normal growth conditions, but Ser/Leu levels change in response to stress. Remarkably, recombinant C. albicans strains incorporating between 20% and 99% of Leu at CUG sites display a diverse array of phenotypes and produce colonies of variable morphology containing a mixture of yeast, pseudohyphal and hyphal cells. In this work we investigate the role of the CUG codon in the yeast-hypha transition. Our data show that increasing incorporation levels of Leu at CUG sites trigger hyphal initiation under non-inducing conditions by reducing farnesol production, and increasing the degradation of the Nrg1 hyphal repressor. We propose that dual CUG Ser/Leu translation triggers filamentation via the Nrg1 pathway.ImportanceThe unique translation of the CUG codon as both Ser (~97%) and Leu (~3%) plays a key role in the production of high genomic and phenotypic diversity in C. albicans. The molecular mechanisms that support such diversity are poorly understood. Here, we show that increased Leu incorporation at CUG sites induce hyphae formation in media where C. albicans normally grows in the yeast form. The data show that increasing Leu at CUG sites triggers the degradation of the hyphal repressor Nrg1, allowing for full expression of hyphal genes. Since filamentation is important for invasion of host tissues, this work shows how the atypical translation of a single codon may play a critical role in the virulence of all fungi of the CTG clade.

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MicroRNA775 targets a β-(1,3)-galactosyltransferase to regulate growth and development in Arabidopsis thaliana

10.1101/2021.01.28.428559 ◽

2021 ◽

Author(s):

Parneeta Mishra ◽

Akanksha Singh ◽

Ashwani Kumar Verma ◽

Rajneesh Singh ◽

Sribash Roy

Keyword(s):

Arabidopsis Thaliana ◽

Growth And Development ◽

Uv Light ◽

Transcriptional Level ◽

List Type ◽

Phenotypic Analysis ◽

Over Expression ◽

Plant Groups ◽

Diverse Plant

AbstractMicroRNAs are critical regulators of gene expression in plants and other organisms, and are involved in regulating plethora of developmental processes. Evolutionarily, miRNAs can be ancient and conserved across species or recently evolved and young, which are not conserved across diverse plant groups. miR775 is a non-conserved miRNA identified only in Arabidopsis thaliana. Here, we investigated the functional significance of miR775 in A. thaliana and observed that miR775 targets a probable β-(1,3)-galactosyltransferase gene at post transcriptional level. Phenotypic analysis of miR775 over-expression lines and the target mutant suggested miR775 regulates rosette size by elongating petiole length and increasing leaf area. Further, the expression of miR775 was found to be up-regulated in response to UV-B and hypoxia. Our results also suggest that miR775 regulated β-(1,3)-galactosyltransferase may involve in regulating the β-(1,3)-galactan content of arabinogalactans. Collectively, our findings establish a role of miR775 in regulating growth and development in A. thaliana.HighlightsThe role of an uncharacterized microRNA, miR775 has been exploredmiR775 targets a probable β-(1,3)-galactosyltransferase involved in complex carbohydrate biosynthesismiR775 regulates rosette size in A. thaliana and may play role under UV light and hypoxia

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A Review on The Role of VEGF in Tamoxifen Resistance

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520618666180911142259 ◽

2019 ◽

Vol 18 (14) ◽

pp. 2006-2009 ◽

Cited By ~ 2

Author(s):

Sepideh Mansouri ◽

Nikta Feizi ◽

Ali Mahdi ◽

Keivan Majidzadeh-A ◽

Leila Farahmand

Keyword(s):

Feedback Loop ◽

Molecular Mechanisms ◽

Acquired Resistance ◽

Tamoxifen Resistance ◽

Tumor Proliferation ◽

Vegf Receptors ◽

Over Expression ◽

Tamoxifen Resistant ◽

Resistant Cells

Background: Certain molecular deviations can lead to the development of breast cancer. For instance, estrogen and estrogen receptors play a significant role in inducing tumor proliferation. However, the efficacy of endocrine therapy through the administration of anti-estrogen drugs, such as Tamoxifen, is challenged by acquired resistance. Methods: Relevant articles were retrieved from Medline and google scholar. All were screened to select the ones discussing the molecular mechanisms of angiogenesis and Tamoxifen resistance. The molecular interactions contributing in the resistant network were studied from the eligible articles. Results: Tamoxifen resistance occurs as a consequence of over-activated signal transduction pathways such as RTK s dependent cascades. It has been shown that microvessel count was greater in Tamoxifen resistant tissues than in responsive ones. Conclusion: In this review, the interaction between estrogen, Tamoxifen, VEGF, and VEGF receptors (VEGFRs) in Tamoxifen resistant cells has been discussed. VEGF and estrogen-independent growth cascades, especially MAPK have a positive feedback loop in Tamoxifen resistant cells. It has been proposed that over-activated pathways in Tamoxifen resistant cells induce pin1 mediated VEGF over-expression, which in turn result in enhanced activation of MAPK.

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Recent advances in psychoneuroimmunology: Inflammation in psychiatric disorders

Translational Neuroscience ◽

10.2478/s13380-011-0019-0 ◽

2011 ◽

Vol 2 (2) ◽

Cited By ~ 12

Author(s):

Monojit Debnath ◽

Karen Doyle ◽

Camilla Langan ◽

Colm McDonald ◽

Brian Leonard ◽

...

Keyword(s):

Gene Expression ◽

Bipolar Disorder ◽

Psychiatric Disorders ◽

Molecular Mechanisms ◽

Molecular Genetic ◽

Major Depressive ◽

Immune System Dysfunction ◽

Expression Studies ◽

Gene Expression Studies

AbstractPsychiatric disorders are common and complex and their precise biological underpinnings remain elusive. Multiple epidemiological, molecular, genetic and gene expression studies suggest that immune system dysfunction may contribute to the risk for developing psychiatric disorders including schizophrenia, bipolar disorder, and major depressive disorder. However, the precise mechanisms by which inflammation-related events confer such risk are unclear. In this review, we examine the peripheral and central evidence for inflammation in psychiatric disorders and the potential molecular mechanisms implicated including inhibition of neurogenesis, apoptosis, the HPA-axis, the role of brain-derived neurotrophic factor and the interplay between the glutamatergic, dopaminergic and serotonergic neurotransmitter systems.

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Lipase 8 Affects the Pathogenesis of Candida albicans

Infection and Immunity ◽

10.1128/iai.00372-07 ◽

2007 ◽

Vol 75 (10) ◽

pp. 4710-4718 ◽

Cited By ~ 45

Author(s):

Attila Gácser ◽

Frank Stehr ◽

Cathrin Kröger ◽

László Kredics ◽

Wilhelm Schäfer ◽

...

Keyword(s):

Candida Albicans ◽

Open Reading Frame ◽

Infection Model ◽

Reading Frame ◽

Reverse Transcription Pcr ◽

Knockout Mutants ◽

Important Virulence Factor ◽

Actin Promoter ◽

Disruption Method

ABSTRACT The production of lipases can affect microbial fitness and virulence. We examined the role of the lipase 8 (LIP8) gene in the virulence of Candida albicans by constructing Δlip8 strains by the URA-blaster disruption method. Reverse transcription-PCR experiments demonstrated the absence of LIP8 expression in the homozygous knockout mutants. Reconstituted strains and overexpression mutants were generated by introducing a LIP8 open reading frame under control of a constitutive actin promoter. Knockout mutants produced more mycelium, particularly at higher temperatures and pH ≥7. Diminished LIP8 expression resulted in reduced growth in lipid-containing media. Mutants deficient in the LIP8 gene were significantly less virulent in a murine intravenous infection model. The results clearly indicate that Lip8p is an important virulence factor of C. albicans.

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The 5′ Untranslated Region of theEFG1Transcript Promotes Its Translation To Regulate Hyphal Morphogenesis inCandida albicans

mSphere ◽

10.1128/msphere.00280-18 ◽

2018 ◽

Vol 3 (4) ◽

Cited By ~ 2

Author(s):

Prashant R. Desai ◽

Klaus Lengeler ◽

Mario Kapitan ◽

Silas Matthias Janßen ◽

Paula Alepuz ◽

...

Keyword(s):

Candida Albicans ◽

Fungal Pathogen ◽

Untranslated Regions ◽

Regulatory Sequence ◽

Transcriptional Level ◽

Content Type ◽

Reading Frame ◽

Human Fungal Pathogen ◽

Hyphal Morphogenesis ◽

Incandida Albicans

ABSTRACTExtensive 5′ untranslated regions (UTR) are a hallmark of transcripts determining hyphal morphogenesis inCandida albicans. The major transcripts of theEFG1gene, which are responsible for cellular morphogenesis and metabolism, contain a 5′ UTR of up to 1,170 nucleotides (nt). Deletion analyses of the 5′ UTR revealed a 218-nt sequence that is required for production of the Efg1 protein and its functions in filamentation, without lowering the level and integrity of theEFG1transcript. Polysomal analyses revealed that the 218-nt 5′ UTR sequence is required for efficient translation of the Efg1 protein. Replacement of theEFG1open reading frame (ORF) by the heterologous reporter geneCaCBGlucconfirmed the positive regulatory importance of the identified 5′ UTR sequence. In contrast to other reported transcripts containing extensive 5′ UTR sequences, these results indicate the positive translational function of the 5′ UTR sequence in theEFG1transcript, which is observed in the context of the nativeEFG1promoter. It is proposed that the 5′ UTR recruits regulatory factors, possibly during emergence of the native transcript, which aid in translation of theEFG1transcript.IMPORTANCEMany of the virulence traits that makeCandida albicansan important human fungal pathogen are regulated on a transcriptional level. Here, we report an important regulatory contribution of translation, which is exerted by the extensive 5′ untranslated regulatory sequence (5′ UTR) of the transcript for the protein Efg1, which determines growth, metabolism, and filamentation in the fungus. The presence of the 5′ UTR is required for efficient translation of Efg1, to promote filamentation. Because transcripts for many relevant regulators contain extensive 5′ UTR sequences, it appears that the virulence ofC. albicansdepends on the combination of transcriptional and translational regulatory mechanisms.

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Downregulation of S100A2 alleviates pulmonary fibrosis through inhibiting wnt/β-catenin signaling pathway

10.21203/rs.3.rs-23375/v1 ◽

2020 ◽

Author(s):

Guichuan Huang ◽

Jing Zhang ◽

Gang Qing ◽

Daishun Liu ◽

Xin Wang ◽

...

Keyword(s):

Pulmonary Fibrosis ◽

Western Blot ◽

Molecular Mechanisms ◽

Transforming Growth Factor ◽

Epithelial Mesenchymal Transition ◽

A549 Cells ◽

Mesenchymal Transition ◽

Qrt Pcr ◽

Tgf Β1

Abstract Background：Pulmonary fibrosis (PF) is a progressive and lethal disease with poor prognosis. S100A2 plays an important role in the progression of cancer. However, the role of S100A2 in PF has not been reported yet. In this study, we explored the potential role of S100A2 in PF and its potential molecular mechanisms. Methods: First, we analyzed S100A2 expression of patients with PF by retrieving RNA-sequencing datasets from Gene Expression Omnibus (GEO) database. Next, we detected the expression of S100A2 in patients with PF using quantitative real time PCR (qRT-PCR). Then, S100A2 expression was determined with or without the treatment of transforming growth factor-β1 (TGF-β1) in A549 cells. Epithelial-mesenchymal transition (EMT) biomarkers, including E-cadherin，vimentin, and α smooth muscle actin (α-SMA), were identified using qRT-PCR and western blot. Finally, the relevant signalling pathway indicators were detected by western blot. Results: Increased expression of S100A2 was first observed in lung tissues of PF patients. Meanwhile, we found that downregulation of S100A2 inhibited the TGF-β1-induced EMT in A549 cells. Mechanically, TGF-β1 up-regulated β-catenin and phosphorylation of GSK-3β, which was blocked by silencing S100A2 in vitro. Conclusion: These findings demonstrate that downregulation of S100A2 alleviate pulmonary fibrosis via inhibiting EMT. S100A2 is a promising potential target for further understanding the mechanism and developing strategy for the treatment of PF and other EMT-associated disease.

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COX5A over-expression protects cortical neurons from hypoxic ischemic injury in neonatal rats associated with TPI up-regulation

10.21203/rs.2.20060/v2 ◽

2020 ◽

Author(s):

Ya Jiang ◽

Xue Bai ◽

Ting-Ting Li ◽

Mohammed AL Hawwas ◽

Yuan Jin ◽

...

Keyword(s):

Cortical Neurons ◽

Molecular Mechanisms ◽

Cerebral Injury ◽

Neurological Dysfunction ◽

Neurological Injury ◽

Immunofluorescent Staining ◽

Neonatal Rats ◽

Over Expression ◽

Qrt Pcr

Abstract Background: Neonatal hypoxic-ischemic encephalopathy (HIE) represents as a major cause of neonatal morbidity and mortality. However, the underlying molecular mechanisms in brain damage are still not fully elucidated. This study was conducted to determine the specific potential molecular mechanism in the hypoxic-ischemic induced cerebral injury. Methods: Here, hypoxic-ischemic (HI) animal models were established and primary cortical neurons were subjected to oxygen-glucose deprivation (OGD) to mimic HIE model in-vivo and in - vitro . The HI-induced neurological injury was evaluated by Zea-longa scores, Triphenyte-trazoliumchloride (TTC) staining the Terminal Deoxynucleotidyl Transferased Utp Nick End Labeling (TUNEL) and immunofluorescent staining. Then the expression of Cytochrome c oxidase subunit 5a (COX5A) was determined by immunohistochemistry, western blotting (WB) and quantitative real time Polymerase Chain Reaction (qRT-PCR) techniques. Moreover, HSV-mediated COX5A over-expression virus was transducted into OGD neurons to explore the role of COX5A in - vitro , and the underlying mechanism was predicted by GeneMANIA, then verified by WB and qRT-PCR. Results: HI induced a severe neurological dysfunction, brain infarction, and cell apoptosis as well as obvious neuron loss in neonatal rats, in corresponding to the decrease on the expression of COX5A in both sides of the brain . What’s more, COX5A over-expression significantly promoted the neuronal survival, reduced the apoptosis rate, and markedly increased the neurites length after OGD. Moreover, Triosephosephate isomerase (TPI) was predicted as physical interactions with COX5A, and COX5A over-expression largely increased the expressional level of TPI. Conclusions: The present findings suggest that COX5A plays an important role in promoting neurological recovery after HI, and this process is related to TPI up-regulation.

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Molecular studies into cell biological role of Copine-4 in Retinal Ganglion Cells

PLoS ONE ◽

10.1371/journal.pone.0255860 ◽

2021 ◽

Vol 16 (11) ◽

pp. e0255860

Author(s):

Manvi Goel ◽

Angel M. Aponte ◽

Graeme Wistow ◽

Tudor C. Badea

Keyword(s):

Retinal Ganglion Cells ◽

Molecular Mechanisms ◽

Ganglion Cells ◽

Mass Spectrometry Analysis ◽

Hek293 Cells ◽

Retinal Cell ◽

Interacting Proteins ◽

Retinal Ganglion ◽

Over Expression

The molecular mechanisms underlying morphological diversity in retinal cell types are poorly understood. We have previously reported that several members of the Copine family of Ca-dependent membrane adaptors are expressed in Retinal Ganglion Cells and transcriptionally regulated by Brn3 transcription factors. Several Copines are enriched in the retina and their over-expression leads to morphological changes -formation of elongated processes-, reminiscent of neurites, in HEK293 cells. However, the role of Copines in the retina is largely unknown. We now investigate Cpne4, a Copine whose expression is restricted to Retinal Ganglion Cells. Over-expression of Cpne4 in RGCs in vivo led to formation of large varicosities on the dendrites but did not otherwise visibly affect dendrite or axon formation. Protein interactions studies using yeast two hybrid analysis from whole retina cDNA revealed two Cpne4 interacting proteins–Host Cell Factor 1 and Morn2. Mass Spectrometry analysis of retina lysate pulled down using Cpne4 or its vonWillebrand A domain showed 207 interacting proteins. A Gene Ontology analysis of the discovered proteins suggests that Cpne4 is involved in several metabolic and signaling pathways in the retina.

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