CAZymes from the thermophilic fungus Thermoascus aurantiacus are induced by C5 and C6 sugars

Abstract Background Filamentous fungi are excellent lignocellulose degraders, which they achieve through producing carbohydrate active enzymes (CAZymes). CAZyme production is highly orchestrated and gene expression analysis has greatly expanded understanding of this important biotechnological process. The thermophilic fungus Thermoascus aurantiacus secretes highly active thermostable enzymes that enable saccharifications at higher temperatures; however, the genome-wide measurements of gene expression in response to CAZyme induction are not understood. Results A fed-batch system with plant biomass-derived sugars d-xylose, l-arabinose and cellobiose established that these sugars induce CAZyme expression in T. aurantiacus. The C5 sugars induced both cellulases and hemicellulases, while cellobiose specifically induced cellulases. A minimal medium formulation was developed to enable gene expression studies of T. aurantiacus with these inducers. It was found that d-xylose and l-arabinose strongly induced a wide variety of CAZymes, auxiliary activity (AA) enzymes and carbohydrate esterases (CEs), while cellobiose facilitated lower expression of mostly cellulase genes. Furthermore, putative orthologues of different unfolded protein response genes were up-regulated during the C5 sugar feeding together with genes in the C5 sugar assimilation pathways. Conclusion This work has identified two additional CAZyme inducers for T. aurantiacus, l-arabinose and cellobiose, along with d-xylose. A combination of biochemical assays and RNA-seq measurements established that C5 sugars induce a suite of cellulases and hemicellulases, providing paths to produce broad spectrum thermotolerant enzymatic mixtures.

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Uncovering CAZyme Induction in the Thermophilic Fungus Thermoascus Aurantiacus

10.21203/rs.3.rs-597506/v1 ◽

2021 ◽

Author(s):

Raphael Gabriel ◽

Rebecca Mueller ◽

Lena Floerl ◽

Cynthia Hopson ◽

Simon Harth ◽

...

Keyword(s):

Plant Biomass ◽

Thermophilic Fungus ◽

Thermoascus Aurantiacus ◽

Rna Seq ◽

Thermostable Enzymes ◽

Unfolded Protein ◽

Highly Active ◽

Biochemical Assays ◽

Genome Wide ◽

Protein Response

Abstract Background: Filamentous fungi are excellent lignocellulose degraders, which they achieve through producing carbohydrate active enzymes (CAZymes). CAZyme production is highly orchestrated and the application of –omics methods such as RNA-Seq has greatly expanded understanding of this important biotechnological process. The thermophilic fungus Thermoascus aurantiacus secretes high amounts of highly active thermostable enzymes that enable saccharifications at higher temperatures; however, the genome-wide response to CAZyme induction is not understood. Results: A fed-batch system with plant biomass-derived sugars D-xylose, L-arabinose and cellobiose established that these sugars induce CAZyme expression in T. aurantiacus. The C5 sugars induced both cellulases and hemicellulases, while cellobiose specifically induced cellulases. A minimal medium formulation was developed to enable RNA-seq studies of T. aurantiacus with these inducers. It was found that D-xylose and L-arabinose strongly induced a wide variety of CAZymes, auxiliary activity (AA) enzymes and carbohydrate esterases (CEs), while cellobiose facilitated lower expression of mostly cellulase genes. Furthermore, putative orthologues of different unfolded protein response genes were up-regulated during the C5 sugar feeding together with genes in the C5 sugar assimilation pathways. Conclusion: This work has identified two additional CAZyme inducers for T. aurantiacus, L-arabinose and cellobiose, along with D-xylose. A combination of biochemical assays and RNA-seq measurements established that C5 sugars induce a suite of cellulases and hemicellulases, providing a path to produce a broad spectrum thermotolerant enzymatic mixture for deconstruction of plant biomass.

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Transcriptome Analysis of Recombinant Protein Secretion by Aspergillus nidulans and the Unfolded-Protein Response In Vivo

Applied and Environmental Microbiology ◽

10.1128/aem.71.5.2737-2747.2005 ◽

2005 ◽

Vol 71 (5) ◽

pp. 2737-2747 ◽

Cited By ~ 61

Author(s):

Andrew H. Sims ◽

Manda E. Gent ◽

Karin Lanthaler ◽

Nigel S. Dunn-Coleman ◽

Stephen G. Oliver ◽

...

Keyword(s):

Gene Expression ◽

Recombinant Protein ◽

Unfolded Protein Response ◽

Aspergillus Nidulans ◽

Filamentous Fungi ◽

Protein Secretion ◽

Unfolded Protein ◽

The Unfolded Protein Response ◽

Protein Response

ABSTRACT Filamentous fungi have a high capacity for producing large amounts of secreted proteins, a property that has been exploited for commercial production of recombinant proteins. However, the secretory pathway, which is key to the production of extracellular proteins, is rather poorly characterized in filamentous fungi compared to yeast. We report the effects of recombinant protein secretion on gene expression levels in Aspergillus nidulans by directly comparing a bovine chymosin-producing strain with its parental wild-type strain in continuous culture by using expressed sequence tag microarrays. This approach demonstrated more subtle and specific changes in gene expression than those observed when mimicking the effects of protein overproduction by using a secretion blocker. The impact of overexpressing a secreted recombinant protein more closely resembles the unfolded-protein response in vivo.

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Enforced dimerization between XBP1s and ATF6f enhances the protective effects of the unfolded protein response (UPR) in models of neurodegeneration

10.1101/2020.11.17.387480 ◽

2020 ◽

Author(s):

René L. Vidal ◽

Denisse Sepulveda ◽

Paulina Troncoso-Escudero ◽

Paula Garcia-Huerta ◽

Constanza Gonzalez ◽

...

Keyword(s):

Gene Expression ◽

Unfolded Protein Response ◽

Target Genes ◽

Cell Function ◽

Alpha Synuclein ◽

Protective Effects ◽

Unfolded Protein ◽

The Unfolded Protein Response ◽

Protein Response

AbstractAlteration to endoplasmic reticulum (ER) proteostasis is observed on a variety of neurodegenerative diseases associated with abnormal protein aggregation. Activation of the unfolded protein response (UPR) enables an adaptive reaction to recover ER proteostasis and cell function. The UPR is initiated by specialized stress sensors that engage gene expression programs through the concerted action of the transcription factors ATF4, ATF6f, and XBP1s. Although UPR signaling is generally studied as unique linear signaling branches, correlative evidence suggests that ATF6f and XBP1s may physically interact to regulate a subset of UPR-target genes. Here, we designed an ATF6f-XBP1s fusion protein termed UPRplus that behaves as a heterodimer in terms of its selective transcriptional activity. Cell-based studies demonstrated that UPRplus has stronger an effect in reducing the abnormal aggregation of mutant huntingtin and alpha-synuclein when compared to XBP1s or ATF6 alone. We developed a gene transfer approach to deliver UPRplus into the brain using adeno-associated viruses (AAVs) and demonstrated potent neuroprotection in vivo in preclinical models of Parkinson’s and Huntington’s disease. These results support the concept where directing UPR-mediated gene expression toward specific adaptive programs may serve as a possible strategy to optimize the beneficial effects of the pathway in different disease conditions.

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PERK/eIF2α signaling inhibits HIF-induced gene expression during the unfolded protein response via YB1-dependent regulation of HIF1α translation

Nucleic Acids Research ◽

10.1093/nar/gky127 ◽

2018 ◽

Vol 46 (8) ◽

pp. 3878-3890 ◽

Cited By ~ 11

Author(s):

Iglika G Ivanova ◽

Catherine V Park ◽

Adrian I Yemm ◽

Niall S Kenneth

Keyword(s):

Gene Expression ◽

Unfolded Protein Response ◽

Unfolded Protein ◽

The Unfolded Protein Response ◽

Protein Response

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IreA controls endoplasmic reticulum stress-induced autophagy and survival through homeostasis recovery

Molecular and Cellular Biology ◽

10.1128/mcb.00054-18 ◽

2018 ◽

pp. MCB.00054-18 ◽

Cited By ~ 6

Author(s):

Eunice Domínguez-Martín ◽

Laura Ongay-Larios ◽

Laura Kawasaki ◽

Olivier Vincent ◽

Gerardo Coello ◽

...

Keyword(s):

Gene Expression ◽

Endoplasmic Reticulum ◽

Er Stress ◽

Cell Survival ◽

Eukaryotic Cell ◽

Functional Link ◽

Unfolded Protein ◽

Transcriptional Changes ◽

The Unfolded Protein Response ◽

Protein Response

The Unfolded Protein Response (UPR) is an adaptive pathway that restores cellular homeostasis after endoplasmic reticulum (ER) stress. The ER-resident kinase/ribonuclease Ire1 is the only UPR sensor conserved during evolution. Autophagy, a lysosomal degradative pathway, also contributes to the recovery of cell homeostasis after ER-stress but the interplay between these two pathways is still poorly understood. We describe the Dictyostelium discoideum ER-stress response and characterize its single bonafide Ire1 orthologue, IreA. We found that tunicamycin (TN) triggers a gene-expression reprogramming that increases the protein folding capacity of the ER and alleviates ER protein load. Further, IreA is required for cell-survival after TN-induced ER-stress and is responsible for nearly 40% of the transcriptional changes induced by TN. The response of Dictyostelium cells to ER-stress involves the combined activation of an IreA-dependent gene expression program and the autophagy pathway. These two pathways are independently activated in response to ER-stress but, interestingly, autophagy requires IreA at a later stage for proper autophagosome formation. We propose that unresolved ER-stress in cells lacking IreA causes structural alterations of the ER, leading to a late-stage blockade of autophagy clearance. This unexpected functional link may critically affect eukaryotic cell survival under ER-stress.

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Development and validation of an unfolded protein response-related gene signature to predict overall survival in HNSCC.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.e18033 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. e18033-e18033

Author(s):

Jun Chen ◽

Bei Zhang

Keyword(s):

Gene Expression ◽

Overall Survival ◽

Unfolded Protein Response ◽

Cox Regression ◽

Risk Group ◽

Gene Signature ◽

Related Gene ◽

Hallmarks Of Cancer ◽

Unfolded Protein ◽

Protein Response

e18033 Background: Genomic expression profiles have enabled the classification of head and neck squamous cell carcinoma (HNSCC) into molecular sub-types and provide prognostic information, which have implications for the personalized treatment of HNSCC beyond clinical and pathological features. Methods: Gene-expression profiling was identified in TCGA- HNSCC (n = 492) and validated with the Gene Expression Ominibus (GEO) dataset(n = 270) for which RNA sequencing data and clinical covariates were available. A single-sample gene set enrichment analysis (ssGSEA) algorithm were used to quantified the levels of various hallmarks of cancer. And LASSO Cox regression model was used to screen robust prognostic biomarkers to identify the best set of survival-associated gene signatures in HNSCC. Statistical analyses were performed using R version 3.4.4. Results: We identified unfolded protein response as the primary risk factor for survival（cox coefficient = 17.4 [8.4-26.3], P < 0.001）among various hallmarks of cancer in TCGA- HNSCC. And unfolded protein response ssGESA scores were significantly elevated in patients who died during follow up (P = 0.009). Kaplan-Meier analysis showed that patients with low ssGSEA scores of unfolded protein response exhibited better OS (HR = 0.69, P = 0.008). And we established an unfolded protein response-related gene signature based on lasso cox. We then apply the unfolded protein response -related gene signature to classify patients into the high risk group and the low risk group with the cutoff of 0.18. Adjusted for stage，age，gender, our signature was an independent risk factor for overall survival in TCGA cohorts (HR = 0.39 [0.28-0.53],P = < 0.001). In external independent cohorts, similar results were observed. In the validation cohort GEO65858, the patients with high unfolded protein response score showed longer survival (HR = 0.62 [0.38-1.0], P = 0.049). And adjusted for stage，age，HPV state, the multivariate cox regression analysis showed that unfolded protein response-related gene signature exhibited an independent risk prediction for overall survival in 270 patients with HNSCC (HR = 0.57 [0.35-0.94], P = 0.026). Conclusions: By analyzing the gene-expression data with bioinformation approach, we developed and validated a risk prediction model with unfolded protein response -related expression scores in HNSCC, which have the potential to identify patients who could have better overall survival.

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