ABSTRACT
Gliomas are the most common primary tumors of the central nervous system, with approximately half of patients presenting with the most aggressive form of glioblastoma. Although several molecular markers for glioma have been identified, they are not sufficient to predict the prognosis due to the extensive genetic heterogeneity within glioma. Our study reveals that the ratio of IMPDH1 to IMPDH2 expression levels serves as a molecular indicator for glioma treatment prognosis. Patients with a higher IMPDH1/IMPDH2 ratio exhibit a worse prognosis, while those with a lower ratio display a more favorable prognosis. We further demonstrate that IMPDH1 plays a crucial role in maintaining cellular GTP/GDP levels following DNA damage compared to IMPDH2. In the absence of IMPDH1, cells experience an imbalance in the GTP/GDP ratio, impairing DNA damage repair capabilities and rendering them more sensitive to TMZ. This study not only introduces a novel prognostic indicator for glioma clinical diagnosis but also offers innovative insights for precise and stratified glioma treatment.
Subject(s)
Glioma , IMP Dehydrogenase , Temozolomide , Humans , Glioma/drug therapy , Glioma/genetics , Glioma/pathology , Glioma/mortality , IMP Dehydrogenase/genetics , IMP Dehydrogenase/metabolism , Temozolomide/therapeutic use , Temozolomide/pharmacology , Prognosis , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Line, Tumor , DNA Damage/drug effects , Female , Male , Guanosine Triphosphate/metabolismABSTRACT
Introduction: Systemic dimorphic fungi pose a significant public health challenge, causing over one million new infections annually. The dimorphic transition between saprophytic mycelia and pathogenic yeasts is strongly associated with the pathogenesis of dimorphic fungi. However, despite the dynamic nature of dimorphic transition, the current omics studies focused on dimorphic transition primarily employ static strategies, partly due to the lack of suitable dynamic analytical methods. Methods: We conducted time-course transcriptional profiling during the dimorphic transition of Talaromyces marneffei, a model organism for thermally dimorphic fungi. To capture non-uniform and nonlinear transcriptional changes, we developed DyGAM-NS (dynamic optimized generalized additive model with natural cubic smoothing). The performance of DyGAM-NS was evaluated by comparison with seven other commonly used time-course analysis methods. Based on dimorphic transition induced genes (DTIGs) identified by DyGAM-NS, cluster analysis was utilized to discern distinct gene expression patterns throughout dimorphic transitions of T. marneffei. Simultaneously, a gene expression regulatory network was constructed to probe pivotal regulatory elements governing the dimorphic transitions. Results: By using DyGAM-NS, model, we identified 5,223 DTIGs of T. marneffei. Notably, the DyGAM-NS model showcases performance on par with or superior to other commonly used models, achieving the highest F1 score in our assessment. Moreover, the DyGAM-NS model also demonstrates potential in predicting gene expression levels throughout temporal processes. The cluster analysis of DTIGs suggests divergent gene expression patterns between mycelium-to-yeast and yeast-to-mycelium transitions, indicating the asymmetrical nature of two transition directions. Additionally, leveraging the identified DTIGs, we constructed a regulatory network for the dimorphic transition and identified two zinc finger-containing transcription factors that potentially regulate dimorphic transition in T. marneffei. Discussion: Our study elucidates the dynamic transcriptional profile changes during the dimorphic transition of T. marneffei. Furthermore, it offers a novel perspective for unraveling the underlying mechanisms of fungal dimorphism, emphasizing the importance of dynamic analytical methods in understanding complex biological processes.
ABSTRACT
BACKGROUND & AIMS: HBsAg loss is only observed in a small proportion of patients with chronic hepatitis B (CHB) who undergo interferon treatment. Investigating the host factors crucial for functional cure of CHB can aid in identifying individuals who would benefit from peginterferon-α (Peg-IFNα) therapy. METHODS: We conducted a genome-wide association study (GWAS) by enrolling 48 patients with CHB who achieved HBsAg loss after Peg-IFNα treatment and 47 patients who didn't. In the validation stage, we included 224 patients, of whom 90 had achieved HBsAg loss, to validate the identified significant single nucleotide polymorphisms. To verify the functional involvement of the candidate genes identified, we performed a series of in vitro and in vivo experiments. RESULTS: GWAS results indicated a significant association between the rs7519753 C allele and serum HBsAg loss in patients with CHB after Peg-IFNα treatment (p = 4.85 × 10-8, odds ratio = 14.47). This association was also observed in two independent validation cohorts. Expression quantitative trait locus analysis revealed higher hepatic TP53BP2 expression in individuals carrying the rs7519753 C allele (p = 2.90 × 10-6). RNA-sequencing of liver biopsies from patients with CHB after Peg-IFNα treatment revealed that hepatic TP53BP2 levels were significantly higher in the HBsAg loss group compared to the HBsAg persistence group (p = 0.035). In vitro and in vivo experiments demonstrated that loss of TP53BP2 decreased interferon-stimulated gene levels and the anti-HBV effect of IFN-α. Mechanistically, TP53BP2 was found to downregulate SOCS2, thereby facilitating JAK/STAT signaling. CONCLUSION: The rs7519753 C allele is associated with elevated hepatic TP53BP2 expression and an increased probability of serum HBsAg loss post-Peg-IFNα treatment in patients with CHB. TP53BP2 enhances the response of the hepatocyte to IFN-α by suppressing SOCS2 expression. IMPACT AND IMPLICATIONS: Chronic hepatitis B (CHB) remains a global public health issue. Although current antiviral therapies are more effective in halting disease progression, only a few patients achieve functional cure for hepatitis B with HBsAg loss, highlighting the urgent need for a cure for CHB. This study revealed that the rs7519753 C allele, which is associated with high expression of hepatic TP53BP2, significantly increases the likelihood of serum HBsAg loss in patients with CHB undergoing Peg-IFNα treatment. This finding not only provides a promising predictor for HBsAg loss but identifies a potential therapeutic target for Peg-IFNα treatment. We believe our results are of great interest to a wide range of stakeholders based on their potential clinical implications.
Subject(s)
Antiviral Agents , Hepatitis B, Chronic , Humans , Antiviral Agents/therapeutic use , Hepatitis B Surface Antigens/genetics , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/genetics , Genome-Wide Association Study , Drug Therapy, Combination , Interferon-alpha/pharmacology , Interferon-alpha/therapeutic use , Polyethylene Glycols/therapeutic use , Hepatitis B e Antigens , Recombinant Proteins/therapeutic use , Treatment Outcome , DNA, Viral/genetics , Apoptosis Regulatory ProteinsABSTRACT
BRCA1 expression is highly regulated to prevent genomic instability and tumorigenesis. Dysregulation of BRCA1 expression correlates closely with sporadic basal-like breast cancer and ovarian cancer. The most significant characteristic of BRCA1 regulation is periodic expression fluctuation throughout the cell cycle, which is important for the orderly progression of different DNA repair pathways throughout the various cell cycle phases and for further genomic stability. However, the underlying mechanism driving this phenomenon is poorly understood. Here, we demonstrate that RBM10-mediated RNA alternative splicing coupled to nonsense-mediated mRNA decay (AS-NMD), rather than transcription, determines the periodic fluctuations in G1/S-phase BRCA1 expression. Furthermore, AS-NMD broadly regulates the expression of period genes, such as DNA replication-related genes, in an uneconomical but more rapid manner. In summary, we identified an unexpected posttranscriptional mechanism distinct from canonical processes that mediates the rapid regulation of BRCA1 as well as other period gene expression during the G1/S-phase transition and provided insights into potential targets for cancer therapy.
Subject(s)
Breast Neoplasms , Nonsense Mediated mRNA Decay , Humans , Female , Alternative Splicing , RNA Splicing , Breast Neoplasms/genetics , Genomic Instability , BRCA1 Protein/genetics , RNA-Binding Proteins/geneticsABSTRACT
MOTIVATION: Transcriptional profiles of diverse tissues provide significant insights in both fundamental and translational researches, while transcriptome information is not always available for tissues that require invasive biopsies. Alternatively, predicting tissue expression profiles from more accessible "surrogate" samples, especially blood transcriptome, has become a promising strategy when invasive procedures are not practical. However, existing approaches ignore tissue-shared intrinsic relevance, inevitably limiting predictive performance. RESULTS: We propose a unified deep learning-based multi-task learning framework, multi-tissue transcriptome mapping (MTM), enabling the prediction of individualized expression profiles from any available tissue of an individual. By jointly leveraging individualized cross-tissue information from reference samples through multi-task learning, MTM achieves superior sample-level and gene-level performance on unseen individuals. With the high prediction accuracy and the ability to preserve individualized biological variations, MTM could facilitate both fundamental and clinical biomedical research. AVAILABILITY AND IMPLEMENTATION: MTM's code and documentation are available upon publication on GitHub (https://github.com/yangence/MTM).
Subject(s)
Transcriptome , HumansABSTRACT
OBJECTIVE: We aimed to investigate the differences of transcriptome profile between 2 groups of high-grade serous ovarian cancer (HGSOC) patients with distinct outcomes and identify potential biomarkers for recurrence. METHODS: RNA sequencing was performed in 2 groups of HGSOC patients with similar demographic characteristics but exhibiting distinct progression-free survival (PFS). Transcriptome data of poor response (PR; PFS ≤6 months) and good response (GR; PFS ≥12 months) group were compared. We employed xCell to evaluate the abundance of 63 cells in tumor microenvironment. The predictive value of recurrence-related tumor infiltration cells was validated in cohort data from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) dataset. The weighted correlation network analysis was performed to identify the genes related to cell infiltration. RESULTS: PR patients exhibited a distinct tumor infiltration immune cells-related transcriptional profile compared to GR patients, such as lower signatures of leukocyte differentiation, activation and chemotaxis. The fraction of T-helper 2 (Th2) cells infiltration was significantly higher in PR group than in GR group. High infiltration of Th2 was significantly associated with unfavorable prognosis in the GEO cohort (area under the curve=0.84 at 6 months recurrence) and TCGA cohort (p=0.008). Genes enriched to extracellular matrix organization and integrin binding were relevant to Th2 infiltration. CONCLUSION: Patients with HGSOC having shorter PFS exhibited a distinct gene signature that related to tumor-infiltrating immune cells. The level of Th2 infiltration could facilitate patient recurrence risk stratification and may be a promising biomarker for prognosis prediction and immune-related treatment.
Subject(s)
Ovarian Neoplasms , Humans , Female , Ovarian Neoplasms/pathology , Th2 Cells/metabolism , Th2 Cells/pathology , Neoplasm Recurrence, Local/pathology , Prognosis , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Tumor MicroenvironmentABSTRACT
BACKGROUND: The liver is responsible for a range of functions in vertebrates, such as metabolism and immunity. In malaria, the liver plays a crucial role in the interaction between the parasite and host. Although malarial hepatitis is a common clinical complication of severe malaria, other malaria-related liver changes have been overlooked during the blood stage of the parasite life-cycle, in contrast to the many studies that have focused on parasite invasion of and replication in the liver during the hepatic stage of the parasite. METHODS: A rodent model of malaria was established using Plasmodium yoelii strain 17XL, a lethal strain of rodent malaria, for liver transcriptomic profiling. RESULTS: Differentially expressed messenger RNAs were associated with innate and adaptive immune responses, while differentially expressed long noncoding RNAs were enriched in the regulation of metabolism-related pathways, such as lipid metabolism. The coexpression network showed that host genes were related to cellular transport and tissue remodeling. Hub gene analysis of P. yoelii indicated that ubiquitination genes that were coexpressed with the host were evolutionarily conserved. CONCLUSIONS: Our analysis yielded evidence of activated immune responses, aberrant metabolic processes and tissue remodeling changes in the livers of mice with malaria during the blood stage of the parasite, which provided a systematic outline of liver responses during Plasmodium infection.
Subject(s)
Malaria , Plasmodium yoelii , Animals , Mice , Transcriptome , Malaria/parasitology , Gene Expression Profiling , Liver/parasitologyABSTRACT
Pathogenic fungi of the genus Cryptococcus can undergo two sexual cycles, involving either bisexual diploidization (after fusion of haploid cells of different mating type) or unisexual diploidization (by autodiploidization of a single cell). Here, we construct a gene-deletion library for 111 transcription factor genes in Cryptococcus deneoformans, and explore the roles of these regulatory networks in the two reproductive modes. We show that transcription factors crucial for bisexual syngamy induce the expression of known mating determinants as well as other conserved genes of unknown function. Deletion of one of these genes, which we term FMP1, leads to defects in bisexual reproduction in C. deneoformans, its sister species Cryptococcus neoformans, and the ascomycete Neurospora crassa. Furthermore, we show that a recently evolved regulatory cascade mediates pre-meiotic unisexual autodiploidization, supporting that this reproductive process is a recent evolutionary innovation. Our findings indicate that genetic circuits with different evolutionary ages govern hallmark events distinguishing unisexual and bisexual reproduction in Cryptococcus.
Subject(s)
Cryptococcus neoformans , Fungal Proteins , Meningitis, Cryptococcal , Cryptococcus neoformans/growth & development , Cryptococcus neoformans/pathogenicity , Fungal Proteins/genetics , Fungal Proteins/metabolism , Genes, Mating Type, Fungal/genetics , Reproduction, Asexual/genetics , Meningitis, Cryptococcal/parasitologyABSTRACT
BACKGROUND: Human endogenous retroviruses (HERVs), the remnants of ancient retroviruses, account for 8% of the human genome, but most have lost their transcriptional abilities under physiological conditions. However, mounting evidence shows that several expressed HERVs do exert biological functions. Here, we systematically characterize physiologically expressed HERVs and examine whether they may give insight into the molecular fundamentals of human development and disease. RESULTS: We systematically identify 13,889 expressed HERVs across normal body sites and demonstrate that they are expressed in body site-specific patterns and also by sex, ethnicity, and age. Analyzing cis-ERV-related quantitative trait loci, we find that 5435 hervRNAs are regulated by genetic variants. Combining this with a genome-wide association study, we elucidate that the dysregulation of expressed HERVs might be associated with various complex diseases, particularly neurodegenerative and psychiatric diseases. We further find that physiologically activated hervRNAs are associated with histone modifications rather than DNA demethylation. CONCLUSIONS: Our results present a locus-specific landscape of physiologically expressed hervRNAs, which represent a hidden layer of genetic architecture in development and disease.
Subject(s)
Endogenous Retroviruses , Humans , Endogenous Retroviruses/genetics , Genome-Wide Association Study , Human Body , Genome, HumanABSTRACT
Intestinal mycobiome dysbiosis plays an important role in the advancement of HIV- and HCV-infected patients. Co-infection with HCV is an important risk factor for exacerbating immune activation in HIV-infected patients, and gut fungal microbial dysbiosis plays an important role. However, no systematic study has been conducted on the intestinal fungal microbiome of HIV/HCV co-infected patients to date. Patients infected with HIV and HCV, either alone or in combination, and healthy volunteers were included. Stool samples were collected for fungal ITS sequencing and for further mycobiome statistical analysis. We found that the abundance of fungal species significantly decreased in the HIV/HCV co-infection group compared to in the healthy control group, while no significant differences were found in the mono-infection groups. Low-CD4 + T-cell patients in the HIV group and high-ALT-level patients in the HCV group were discovered to have a more chaotic fungal community. Furthermore, the opportunistic pathogenic fungal profiles and fungal inter-correlations in the co-infection group became less characteristic but more complicated than those in the mono-infection groups. Intestinal fungal dysregulation occurs in HIV- and HCV-infected patients, and this dysregulation is further complicated in HIV/HCV co-infected patients.
Subject(s)
Coinfection , HIV Infections , Hepatitis C , Mycobiome , Dysbiosis , HIV Infections/complications , Hepacivirus/physiology , Hepatitis C/complications , HumansABSTRACT
Due to overlapping sequences with linear cognates, identifying internal sequences of circular RNA (circRNA) remains a challenge. Recently, we have developed a full-length circRNA sequencing method (circFL-seq) and computational pipeline, to profile ordinary and fusion circRNA at the isoform level. Compared to short-read RNA-seq, rolling circular reverse transcription and nanopore long-read sequencing of circFL-seq make circRNA reads more than tenfold enriched, and show advantages for identification of both short (<100 nt) and long (>2,000 nt) circRNA transcripts. circFL-seq allows identification of differential alternative splicing suggested wide application prospects for functional studies of internal sequences in circRNAs. In addition, the experimental protocol and computational pipeline of circFL-seq shows better sensitivity and precision for identification of back-splicing junctions than current long-read sequencing methods. Together, the accurate identification and quantification of full-length circRNAs makes circFL-seq a potential tool for large-scale screening of functional circRNAs.
ABSTRACT
Emerging evidence showed that lncRNAs play important roles in a wide range of biological processes of fungi such as Saccharomyces cerevisiae. However, systemic identification of lncRNAs in non-model fungi is a challenging task as the efficiency of rRNA removal has been proved to be affected by mismatches of universal rRNA-targeting probes of commercial kits, which forces deeper sequencing depth and increases costs. Here, we developed a low-cost and simple rRNA depletion method (rProbe) that could efficiently remove more than 99% rRNA in both yeast and mycelium samples of Talaromyces marneffei. The efficiency and robustness of rProbe were demonstrated to outperform the Illumina Ribo-Zero kit. Using rProbe RNA-seq, we identified 115 differentially expressed lncRNAs and constructed lncRNA-mRNA co-expression network related to dimorphic switch of T. marneffei. Our rRNA removal method has the potential to be a useful tool to explore non-coding transcriptomes of non-model fungi by adjusting rRNA probe sequences species specifically.
ABSTRACT
Liquid-liquid phase separation (LLPS) is an important mechanism that mediates the formation of biomolecular condensates. Despite the immense interest in LLPS, phase-separated proteins verified by experiments are still limited, and identification of phase-separated proteins at proteome-scale is a challenging task. Multivalent interaction among macromolecules is the driving force of LLPS, which suggests that phase-separated proteins may harbor distinct biological characteristics in protein-protein interactions (PPIs). In this study, we constructed an integrated human PPI network (HPIN) and mapped phase-separated proteins into it. Analysis of the network parameters revealed differences of network topology between phase-separated proteins and others. The results further suggested the efficiency when applying topological similarities in distinguishing components of MLOs. Furthermore, we found that affinity purification mass spectrometry (AP-MS) detects PPIs more effectively than yeast-two hybrid system (Y2H) in phase separation-driven condensates. Our work provides the first global view of the distinct network topology of phase-separated proteins in human interactome, suggesting incorporation of PPI network for LLPS prediction in further studies.
Subject(s)
Mass Spectrometry/methods , Protein Interaction Mapping/methods , Proteins/chemistry , Proteins/metabolism , Biomolecular Condensates/chemistry , Biophysical Phenomena , Cluster Analysis , Humans , Intrinsically Disordered Proteins/chemistry , Intrinsically Disordered Proteins/metabolism , Organelles/metabolism , Phase Transition , Two-Hybrid System TechniquesABSTRACT
Circular RNAs (circRNAs) are involved in various biological processes and disease pathogenesis. However, only a small number of functional circRNAs have been identified among hundreds of thousands of circRNA species, partly because most current methods are based on circular junction counts and overlook the fact that a circRNA is formed from the host gene by back-splicing (BS). To distinguish the expression difference originating from BS or the host gene, we present differentially expressed back-splicing (DEBKS), a software program to streamline the discovery of differential BS events between two rRNA-depleted RNA sequencing (RNA-seq) sample groups. By applying to real and simulated data and employing RT-qPCR for validation, we demonstrate that DEBKS is efficient and accurate in detecting circRNAs with differential BS events between paired and unpaired sample groups. DEBKS is available at https://github.com/yangence/DEBKS as open-source software.
Subject(s)
RNA, Circular , RNA , RNA, Circular/metabolism , RNA/genetics , RNA/metabolism , Software , Sequence Analysis, RNA/methods , RNA, RibosomalABSTRACT
BACKGROUND: Aetiology detection is crucial in the diagnosis and treatment of ventilator-associated pneumonia (VAP). However, the detection method needs improvement. In this study, we used Nanopore sequencing to build a quick detection protocol and compared the efficiency of different methods for detecting 7 VAP pathogens. METHODS: The endotracheal aspirate (ETA) of 83 patients with suspected VAP from Peking University Third Hospital (PUTH) was collected, saponins were used to deplete host genomes, and PCR- or non-PCR-amplified library construction methods were used and compared. Sequence was performed with MinION equipment and local data analysis methods were used for sequencing and data analysis. RESULTS: Saponin depletion effectively removed 11 of 12 human genomes, while most pathogenic bacterial genome results showed no significant difference except for S. pneumoniae. Moreover, the average sequence time decreased from 19.6 h to 3.62 h. The non-PCR amplification method and PCR amplification method for library build has a similar average sensitivity (85.8% vs. 86.35%), but the non-PCR amplification method has a better average specificity (100% VS 91.15%), and required less time. The whole method takes 5-6 h from ETA extraction to pathogen classification. After analysing the 7 pathogens enrolled in our study, the average sensitivity of metagenomic sequencing was approximately 2.4 times higher than that of clinical culture (89.15% vs. 37.77%), and the average specificity was 98.8%. CONCLUSIONS: Using saponins to remove the human genome and a non-PCR amplification method to build libraries can be used for the identification of pathogens in the ETA of VAP patients within 6 h by MinION, which provides a new approach for the rapid identification of pathogens in clinical departments.
Subject(s)
Bronchoalveolar Lavage Fluid/microbiology , DNA, Bacterial/analysis , Metagenomics/methods , Pneumonia, Pneumococcal/diagnosis , Pneumonia, Ventilator-Associated/diagnosis , Streptococcus pneumoniae/genetics , Female , Follow-Up Studies , Humans , Intensive Care Units , Male , Middle Aged , Pneumonia, Pneumococcal/microbiology , Pneumonia, Ventilator-Associated/microbiology , Retrospective StudiesABSTRACT
The yeast-to-hypha transition is tightly associated with pathogenicity in many human pathogenic fungi, such as the model fungal pathogen Cryptococcus neoformans, which is responsible for approximately 180,000 deaths annually. In this pathogen, the yeast-to-hypha transition can be initiated by distinct stimuli: mating stimulation or glucosamine (GlcN), the monomer of cell wall chitosan. However, it remains poorly understood how the signal specificity for Cryptococcus morphological transition by disparate stimuli is ensured. Here, by integrating temporal expression signature analysis and phenome-based clustering evaluation, we demonstrate that GlcN specifically triggers a unique cellular response, which acts as a critical determinant underlying the activation of GlcN-induced filamentation (GIF). This cellular response is defined by an unusually hyperactive cell wall synthesis that is highly ATP-consuming. A novel cell surface protein Gis1 was identified as the indicator molecule for the GlcN-induced cell wall response. The Mpk1-directed cell wall pathway critically bridges global cell wall gene induction and intracellular ATP supply, ensuring the Gis1-dependent cell wall response and the stimulus specificity of GIF. We further reveal that the ability of Mpk1 to coordinate the cell wall response and GIF activation is conserved in different Cryptococcus pathogens. Phosphoproteomics-based profiling together with genetic and phenotypic analysis revealed that the Mpk1 kinase mediates the regulatory specificity of GIF through a coordinated downstream regulatory network centered on Skn7 and Crz1. Overall, our findings discover an unprecedented and conserved cell wall biosynthesis-dependent fungal differentiation commitment mechanism, which enables the signal specificity of pathogenicity-related dimorphism induced by GlcN in Cryptococcus pathogens.
Subject(s)
Cell Wall/genetics , Cryptococcus neoformans/genetics , Glucosamine/genetics , Virulence/genetics , Fungal Proteins/genetics , Gene Deletion , Gene Expression Regulation, Fungal/geneticsABSTRACT
Candida glabrata is one of the most prevalent causative pathogens of invasive candidiasis, and multidrug-resistant strains are emerging. We identified two clinical isolates of C. glabrata, BMU10720 and BMU10722 sequentially isolated from one patient with multidrug-resistance to posaconazole (POS), caspofungin (CAS), micafungin (MCF), and anidulafungin (ANF). Overexpression of ERG11 in BMU10720 and CDR1 in BMU10722 were detected at basal level. When exposed to POS, CDR1 was significantly up-regulated in both isolates compared with susceptible reference strain, while ERG11 was up-regulated considerably only in BMU10720. PDR1 sequencing revealed that both isolates harbored P76S, P143T, and D243N substitutions, while ERG11 was intact. Cdr1 inhibitor FK520 reversed POS-resistance by down-regulating ERG11 expression. FKS sequencing revealed that both isolates harbored S663P substitution in FKS2, and four single nucleotide polymorphisms (SNPs) existed in FKS2 genes between BMU10720 and BMU10722, while FKS1 was intact. Both FKS1 and FKS2 were up-regulated by CAS in BMU10720 and BMU10722. FK520 down-regulated FKS2 expression induced by CAS through inhibiting calcineurin, resulting in synergic effect with echinocandins as well as Congo Red and Calcofluor White, two cell wall-perturbing agents. In conclusion, the multidrug-resistance of C. glabrata isolates in our study was conferred by different mechanisms. CDR1 and ERG11 overexpression in one isolate and only CDR1 overexpression in the other isolate may mediate POS-resistance. S663P mutation in FKS2 and up-regulation of FKS2 may contribute to echinocandin-resistance in both isolates.
ABSTRACT
Circular RNAs (circRNAs) act through multiple mechanisms via their sequence features to fine-tune gene expression networks. Due to overlapping sequences with linear cognates, identifying internal sequences of circRNAs remains a challenge, which hinders a comprehensive understanding of circRNA functions and mechanisms. Here, based on rolling circular reverse transcription and nanopore sequencing, we developed circFL-seq, a full-length circRNA sequencing method, to profile circRNA at the isoform level. With a customized computational pipeline to directly identify full-length sequences from rolling circular reads, we reconstructed 77,606 high-quality circRNAs from seven human cell lines and two human tissues. circFL-seq benefits from rolling circles and long-read sequencing, and the results showed more than tenfold enrichment of circRNA reads and advantages for both detection and quantification at the isoform level compared to those for short-read RNA sequencing. The concordance of the RT-qPCR and circFL-seq results for the identification of differential alternative splicing suggested wide application prospects for functional studies of internal variants in circRNAs. Moreover, the detection of fusion circRNAs at the omics scale may further expand the application of circFL-seq. Taken together, the accurate identification and quantification of full-length circRNAs make circFL-seq a potential tool for large-scale screening of functional circRNAs.
Subject(s)
Nanopore Sequencing , RNA, Circular/chemistry , RNA-Seq/methods , Reverse Transcription , Cell Line , Humans , Protein Isoforms/metabolism , RNA-Seq/instrumentationABSTRACT
Recently, mutations in the 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase gene (hmg1) have been identified to be associated with triazole resistance in Aspergillus fumigatus. Here, we describe the first case of the G929C mutation in the hmg1 gene, leading to the W272C amino acid substitution, in a triazole-resistant isolate of A. fumigatus recovered from a chronic cavitary pulmonary aspergillosis patient who failed voriconazole therapy in China.
Subject(s)
HMGB1 Protein , Pulmonary Aspergillosis , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Aspergillus fumigatus/genetics , China , Drug Resistance, Fungal/genetics , Fungal Proteins/genetics , HMGB1 Protein/pharmacology , Humans , Microbial Sensitivity Tests , Mutation , Pulmonary Aspergillosis/drug therapy , Triazoles/pharmacologyABSTRACT
Talaromyces marneffei is an important pathogenic thermally dimorphic fungus causing systemic talaromycosis mainly prevalent in Southeast Asia. The dimorphic transition between mycelium and yeast is considered crucial for the pathogenicity of T. marneffei. However, the lack of genetic toolbox has been a major impediment for understanding its pathogenicity. Here a CRISPR-Cas9 system was developed to facilitate genetic manipulations in this organism. In this study, the CRISPR-Cas9 gene editing system uses a native U6 snRNA promoter from T. marneffei to drive the expression of sgRNA. Employing this system and PEG-mediated protoplast transformation, the sakA gene was mutated. Sanger sequencing confirmed nearly 40% site-directed mutation rate. The phenotype analysis confirmed the sakA gene function in T. marneffei dimorphic transition. Our study provided a powerful genome-manipulating tool, which could accelerate studies on T. marneffei for further revealing the mechanisms of its pathogenicity.