Systems Biology
CompCorona: A web application for comparative transcriptome analyses of coronaviruses reveals SARS-CoV-2-specific host response
Turk J Biol. 2023 Dec 15;47(6):393-405. doi: 10.55730/1300-0152.2673. eCollection 2023.
ABSTRACT
BACKGROUND/AIM: Understanding the mechanism of host transcriptomic response to infection by the SARS-CoV-2 virus is crucial, especially for patients suffering from long-term effects of COVID-19, such as long COVID or pericarditis inflammation, potentially linked to side effects of the SARS-CoV-2 spike proteins. We conducted comprehensive transcriptome and enrichment analyses on lung and peripheral blood mononuclear cells (PBMCs) infected with SARS-CoV-2, as well as on SARS-CoV and MERS-CoV, to uncover shared pathways and elucidate their common disease progression and viral replication mechanisms.
MATERIALS AND METHODS: We developed CompCorona, the first interactive online tool for visualizing gene response variance among the family Coronaviridae through 2D and 3D principal component analysis (PCA) and exploring systems biology variance using pathway plots. We also made preprocessed datasets of lungs and PBMCs infected by SARS-CoV-2, SARS-CoV, and MERS-CoV publicly available through CompCorona.
RESULTS: One remarkable finding from the lung and PBMC datasets for infections by SARS-CoV-2, but not infections by other coronaviruses (CoVs), was the significant downregulation of the angiogenin (ANG) and vascular endothelial growth factor A (VEGFA) genes, both directly involved in epithelial and vascular endothelial cell dysfunction. Suppression of the TNF signaling pathway was also observed in cells infected by SARS-CoV-2, along with simultaneous activation of complement and coagulation cascades and pertussis pathways. The ribosome pathway was found to be universally suppressed across all three viruses. The CompCorona online tool enabled the comparative analysis of 9 preprocessed host transcriptome datasets of cells infected by CoVs, revealing the specific host response differences in cases of SARS-CoV-2 infection. This included identifying markers of epithelial dysfunction via interactive 2D and 3D PCA, Venn diagrams, and pathway plots.
CONCLUSION: Our findings suggest that infection by SARS-CoV-2 might induce pulmonary epithelial dysfunction, a phenomenon not observed in cells infected by other CoVs. The publicly available CompCorona tool, along with the preprocessed datasets of cells infected by various CoVs, constitutes a valuable resource for further research into CoV-associated syndromes.
PMID:38681774 | PMC:PMC11045204 | DOI:10.55730/1300-0152.2673
Cross-platform gene expression profiling of breast cancer: Exploring the relationship between breast cancer grades and gene expression pattern
Heliyon. 2024 Apr 16;10(8):e29736. doi: 10.1016/j.heliyon.2024.e29736. eCollection 2024 Apr 30.
ABSTRACT
Gene expression profiling is a powerful tool that has been extensively used to investigate the underlying biology and etiology of diseases, including cancer. Microarray gene expression analysis enables simultaneous measurement of thousands of mRNA levels. Sophisticated computational approaches have evolved in parallel with the rapid progress in bioassay technologies, enabling more effective analysis of the large and complex datasets that these technologies produce. In this study, we utilized systems biology approaches to examine gene expression profiles across different grades of breast cancer progression. We conducted a meta-analysis of publicly available microarray data to elucidate the molecular mechanisms underlying breast cancer grade classification. Our results suggest that while grade index is commonly used for evaluating cancer progression status in the clinic, the complexity of molecular mechanisms, histological characteristics, and other factors related to patient outcomes raises doubts about the utility of breast cancer grades as a foundation for formulating treatment protocols. Our study underscores the importance of advancing personalized strategies for breast cancer classification and management. More research is crucial to refine diagnostic tools and treatment modalities, aiming for greater precision and tailored care in patient outcomes.
PMID:38681607 | PMC:PMC11053269 | DOI:10.1016/j.heliyon.2024.e29736
Deorphanizing solute carriers in <em>Saccharomyces cerevisiae</em> for secondary uptake of xenobiotic compounds
Front Microbiol. 2024 Apr 12;15:1376653. doi: 10.3389/fmicb.2024.1376653. eCollection 2024.
ABSTRACT
The exchange of small molecules between the cell and the environment happens through transporter proteins. Besides nutrients and native metabolic products, xenobiotic molecules are also transported, however it is not well understood which transporters are involved. In this study, by combining exo-metabolome screening in yeast with transporter characterization in Xenopus oocytes, we mapped the activity of 30 yeast transporters toward six small non-toxic substrates. Firstly, using LC-MS, we determined 385 compounds from a chemical library that were imported and exported by S. cerevisiae. Of the 385 compounds transported by yeast, we selected six compounds (viz. sn-glycero-3-phosphocholine, 2,5-furandicarboxylic acid, 2-methylpyrazine, cefadroxil, acrylic acid, 2-benzoxazolol) for characterization against 30 S. cerevisiae xenobiotic transport proteins expressed in Xenopus oocytes. The compounds were selected to represent a diverse set of chemicals with a broad interest in applied microbiology. Twenty transporters showed activity toward one or more of the compounds. The tested transporter proteins were mostly promiscuous in equilibrative transport (i.e., facilitated diffusion). The compounds 2,5-furandicarboxylic acid, 2-methylpyrazine, cefadroxil, and sn-glycero-3-phosphocholine were transported equilibratively by transporters that could transport up to three of the compounds. In contrast, the compounds acrylic acid and 2-benzoxazolol, were strictly transported by dedicated transporters. The prevalence of promiscuous equilibrative transporters of non-native substrates has significant implications for strain development in biotechnology and offers an explanation as to why transporter engineering has been a challenge in metabolic engineering. The method described here can be generally applied to study the transport of other small non-toxic molecules. The yeast transporter library is available at AddGene (ID 79999).
PMID:38680917 | PMC:PMC11045925 | DOI:10.3389/fmicb.2024.1376653
Tumor invasiveness is regulated by the concerted function of APC, formins, and Arp2/3 complex
iScience. 2024 Apr 8;27(5):109687. doi: 10.1016/j.isci.2024.109687. eCollection 2024 May 17.
ABSTRACT
Tumor cell invasion is the initial step in metastasis, the leading cause of death from cancer. Invasion requires protrusive cellular structures that steer the migration of leader cells emanating from the tumor mass toward neighboring tissues. Actin is central to these processes and is therefore the prime target of drugs known as migrastatics. However, the broad effects of general actin inhibitors limit their therapeutic use. Here, we delineate the roles of specific actin nucleators in tuning actin-rich invasive protrusions and pinpoint potential pharmacological targets. We subject colorectal cancer spheroids embedded in collagen matrix-a preclinical model mirroring solid tumor invasiveness-to pharmacologic and/or genetic treatment of specific actin arrays to assess their roles in invasiveness. Our data reveal coordinated yet distinct involvement of actin networks nucleated by adenomatous polyposis coli, formins, and actin-related protein 2/3 complex in the biogenesis and maintenance of invasive protrusions. These findings may open avenues for better targeted therapies.
PMID:38680662 | PMC:PMC11053316 | DOI:10.1016/j.isci.2024.109687
Exploring TSPAN4 promoter methylation as a diagnostic biomarker for tuberculosis
Front Genet. 2024 Apr 12;15:1380828. doi: 10.3389/fgene.2024.1380828. eCollection 2024.
ABSTRACT
BACKGROUND: Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is a persistent infectious disease threatening human health. The existing diagnostic methods still have significant shortcomings, including a low positivity rate in pathogen-based diagnoses and the inability of immunological diagnostics to detect active TB. Hence, it is urgent to develop new techniques to detect TB more accurate and earlier. This research aims to scrutinize and authenticate DNA methylation markers suitable for tuberculosis diagnosis. Concurrently, Providing a new approach for tuberculosis diagnosis.
METHODS: Blood samples from patients with newly diagnosed tuberculosis and healthy controls (HC) were utilized in this study. Examining methylation microarray data from 40 whole blood samples (22TB + 18HC), we employed two procedures: signature gene methylated position analysis and signature region methylated position analysis to pinpoint distinctive methylated positions. Based on the screening results, diagnostic classifiers are constructed through machine learning, and validation was conducted through pyrosequencing in a separate queue (22TB + 18HC). Culminating in the development of a new tuberculosis diagnostic method via quantitative real-time methylation specific PCR (qMSP).
RESULTS: The combination of the two procedures revealed a total of 10 methylated positions, all of which were located in the promoter region. These 10 signature methylated positions facilitated the construction of a diagnostic classifier, exhibiting robust diagnostic accuracy in both cross-validation and external test sets. The LDA model demonstrated the best classification performance, achieving an AUC of 0.83, specificity of 0.8, and sensitivity of 0.86 on the external test set. Furthermore, the validation of signature methylated positions through pyrosequencing demonstrated high agreement with screening outcomes. Additionally, qMSP detection of 2 potential hypomethylated positions (cg04552852 and cg12464638) exhibited promising results, yielding an AUC of 0.794, specificity of 0.720, and sensitivity of 0.816.
CONCLUSION: Our study demonstrates that the validated signature methylated positions through pyrosequencing emerge as plausible biomarkers for tuberculosis diagnosis. The specific methylation markers in the TSPAN4 gene, identified in whole blood samples, hold promise for improving tuberculosis diagnosis. This approach could significantly enhance diagnostic accuracy and speed, offering a new avenue for early detection and treatment.
PMID:38680421 | PMC:PMC11048481 | DOI:10.3389/fgene.2024.1380828
CK1 and PP1 regulate Rift Valley fever virus genome replication through L protein phosphorylation
Antiviral Res. 2024 Apr 26:105895. doi: 10.1016/j.antiviral.2024.105895. Online ahead of print.
ABSTRACT
Rift Valley fever virus (RVFV) is an arbovirus in the Phenuiviridae family identified initially by the large 'abortion storms' observed among ruminants; RVFV can also infect humans. In humans, there is a wide variation of clinical symptoms ranging from subclinical to mild febrile illness to hepatitis, retinitis, delayed-onset encephalitis, or even hemorrhagic fever. The RVFV is a tri-segmented negative-sense RNA virus consisting of S, M, and L segments. The L segment encodes the RNA-dependent RNA polymerase (RdRp), termed the L protein, which is responsible for both viral mRNA synthesis and genome replication. Phosphorylation of viral RdRps is known to regulate viral replication. This study shows that RVFV L protein is serine phosphorylated and identified Casein Kinase 1 alpha (CK1α) and protein phosphatase 1 alpha (PP1α) as L protein binding partners. Inhibition of CK1 and PP1 through small molecule inhibitor treatment, D4476 and 1E7-03, respectively, caused a change in the phosphorylated status of the L protein. Inhibition of PP1α resulted in increased L protein phosphorylation whereas inhibition of CK1α decreased L protein phosphorylation. It was also found that in RVFV infected cells, PP1α localized to the cytoplasmic compartment. Treatment of RVFV infected cells with CK1 inhibitors reduced virus production in both mammalian and mosquito cells. Lastly, inhibition of either CK1 or PP1 reduced viral genomic RNA levels. These data indicate that L protein is phosphorylated and that CK1 and PP1 play a crucial role in regulating the L protein phosphorylation cycle, which is critical to viral RNA production and viral replication.
PMID:38679165 | DOI:10.1016/j.antiviral.2024.105895
Protocol to measure monosynaptic connections between different cortical regions in mice using cell-pair cross correlogram of spike events
STAR Protoc. 2024 Apr 27;5(2):103035. doi: 10.1016/j.xpro.2024.103035. Online ahead of print.
ABSTRACT
Neuromodulation can facilitate interactions between neurons to rescue impaired brain function after stroke. Here, we present a protocol for measuring putative monosynaptic connections between different cortical regions. We detail procedures for tetrode fabrication, implantation surgery, stroke induction in mice, multi-site in vivo electrophysiological recording, units clustering, principal neuron/interneuron classification, and functional connection analysis. This protocol allows us to understand the mechanisms of stroke recovery. For complete details on the use and execution of this protocol, please refer to Wang et al.1.
PMID:38678571 | DOI:10.1016/j.xpro.2024.103035
O-GlcNAcylation of RBM14 contributes to elevated cellular O-GlcNAc through regulation of OGA protein stability
Cell Rep. 2024 Apr 27;43(5):114163. doi: 10.1016/j.celrep.2024.114163. Online ahead of print.
ABSTRACT
Dysregulation of O-GlcNAcylation has emerged as a potential biomarker for several diseases, particularly cancer. The role of OGT (O-GlcNAc transferase) in maintaining O-GlcNAc homeostasis has been extensively studied; nevertheless, the regulation of OGA (O-GlcNAcase) in cancer remains elusive. Here, we demonstrated that the multifunctional protein RBM14 is a regulator of cellular O-GlcNAcylation. By investigating the correlation between elevated O-GlcNAcylation and increased RBM14 expression in lung cancer cells, we discovered that RBM14 promotes ubiquitin-dependent proteasomal degradation of OGA, ultimately mediating cellular O-GlcNAcylation levels. In addition, RBM14 itself is O-GlcNAcylated at serine 521, regulating its interaction with the E3 ligase TRIM33, consequently affecting OGA protein stability. Moreover, we demonstrated that mutation of serine 521 to alanine abrogated the oncogenic properties of RBM14. Collectively, our findings reveal a previously unknown mechanism for the regulation of OGA and suggest a potential therapeutic target for the treatment of cancers with dysregulated O-GlcNAcylation.
PMID:38678556 | DOI:10.1016/j.celrep.2024.114163
Effect of metformin and metformin/linagliptin on gut microbiota in patients with prediabetes
Sci Rep. 2024 Apr 27;14(1):9678. doi: 10.1038/s41598-024-60081-y.
ABSTRACT
Lifestyle modifications, metformin, and linagliptin reduce the incidence of type 2 diabetes (T2D) in people with prediabetes. The gut microbiota (GM) may enhance such interventions' efficacy. We determined the effect of linagliptin/metformin (LM) vs metformin (M) on GM composition and its relationship to insulin sensitivity (IS) and pancreatic β-cell function (Pβf) in patients with prediabetes. A cross-sectional study was conducted at different times: basal, six, and twelve months in 167 Mexican adults with prediabetes. These treatments increased the abundance of GM SCFA-producing bacteria M (Fusicatenibacter and Blautia) and LM (Roseburia, Bifidobacterium, and [Eubacterium] hallii group). We performed a mediation analysis with structural equation models (SEM). In conclusion, M and LM therapies improve insulin sensitivity and Pβf in prediabetics. GM is partially associated with these improvements since the SEM models suggest a weak association between specific bacterial genera and improvements in IS and Pβf.
PMID:38678119 | DOI:10.1038/s41598-024-60081-y
The anatomical structure of sex differences in trust propensity: A voxel-based morphometry study
Cortex. 2024 Apr 8:S0010-9452(24)00089-3. doi: 10.1016/j.cortex.2024.02.018. Online ahead of print.
ABSTRACT
Trust is a key component of human relationships. Sex differences in trust behavior have been elucidated by parental investment theory and social role theory, attributing men's higher trust propensity to their increased engagement in physically and socially risky activities aimed at securing additional resources. Although sex differences in trust behavior exist and the neuropsychological signatures of trust are known, the underlying anatomical structure of sex differences is still unexplored. Our study aimed to investigate the anatomical structure of sex differences in trust behavior toward strangers (i.e., trust propensity, TP) by employing voxel-based morphometry (VBM) in a sample of healthy young adults. We collected behavioral data for TP as measured with participants in the role of trustors completing the one-shot trust game (TG) with anonymous partners as trustees. We conducted primary region of interest (ROI) and exploratory whole-brain (WB) VBM analyses of high-resolution structural images to test for the association between TP and regional gray matter volume (GMV) associated with sex differences. Confirming previous studies, our behavioral results demonstrated that men trusted more than women during the one-shot TG. Our WB analysis showed a greater GMV related to TP in men than women in the precuneus (PreC), whereas our ROI analysis in regions of the default-mode network (dorsomedial prefrontal cortex [dmPFC], PreC, superior temporal gyrus) to simulate the partner's trustworthiness, central-executive network (ventrolateral PFC) to implement a calculus-based trust strategy, and action-perception network (precentral gyrus) to performance cost-benefit calculations, as proposed by a neuropsychoeconomic model of trust. Our findings advance the neuropsychological understanding of sex differences in TP, which has implications for interpersonal partnerships, financial transactions, and societal engagements.
PMID:38677959 | DOI:10.1016/j.cortex.2024.02.018
Shade stress triggers ethylene biosynthesis to accelerate soybean senescence and impede nitrogen remobilization
Plant Physiol Biochem. 2024 Apr 23;210:108658. doi: 10.1016/j.plaphy.2024.108658. Online ahead of print.
ABSTRACT
In gramineae-soybean intercropping systems, shade stress caused by taller plants impacts soybean growth specifically during the reproductive stage. However, the effects of shade stress on soybean senescence remain largely unexplored. In this research, we applied artificial shade treatments with intensities of 75% (S75) and 50% (S50) to soybean plants at the onset of flowering to simulate the shade stress experienced by soybeans in the traditional and optimized maize-soybean intercropping systems, respectively. Compared to the normal light control, both shade treatments led to a rapid decline in the dry matter content of soybean vegetative organs and accelerated their abscission. Moreover, shade treatments triggered the degradation of chlorophyll and soluble proteins in leaves and increased the expression of genes associated with leaf senescence. Metabolic profiling further revealed that ethylene biosynthesis and signal transduction were induced by shade treatment. In addition, the examination of nitrogen content demonstrated that shade treatments impeded the remobilization of nitrogen in vegetative tissues, consequently reducing the seed nitrogen harvest. It's worth noting that these negative effects were less pronounced under the S50 treatment compared to the S75 treatment. Taken together, this research demonstrates that shade stress during the reproductive stage accelerates soybean senescence and impedes nitrogen remobilization, while optimizing the field layout to improve soybean growth light conditions could mitigate these challenges in the maize-soybean intercropping system.
PMID:38677188 | DOI:10.1016/j.plaphy.2024.108658
Modeling cardiomyocyte signaling and metabolism predicts genotype-to-phenotype mechanisms in hypertrophic cardiomyopathy
Comput Biol Med. 2024 Apr 24;175:108499. doi: 10.1016/j.compbiomed.2024.108499. Online ahead of print.
ABSTRACT
Familial hypertrophic cardiomyopathy (HCM) is a significant precursor of heart failure and sudden cardiac death, primarily caused by mutations in sarcomeric and structural proteins. Despite the extensive research on the HCM genotype, the complex and context-specific nature of many signaling and metabolic pathways linking the HCM genotype to phenotype has hindered therapeutic advancements for patients. Here, we have developed a computational model of HCM encompassing cardiomyocyte signaling and metabolic networks and their associated interactions. Utilizing a stochastic logic-based ODE approach, we linked cardiomyocyte signaling to the metabolic network through a gene regulatory network and post-translational modifications. We validated the model against published data on activities of signaling species in the HCM context and transcriptomes of two HCM mouse models (i.e., R403Q-αMyHC and R92W-TnT). Our model predicts that HCM mutation induces changes in metabolic functions such as ATP synthase deficiency and a transition from fatty acids to carbohydrate metabolism. The model indicated major shifts in glutamine-related metabolism and increased apoptosis after HCM-induced ATP synthase deficiency. We predicted that the transcription factors STAT, SRF, GATA4, TP53, and FoxO are the key regulators of cardiomyocyte hypertrophy and apoptosis in HCM in alignment with experiments. Moreover, we identified shared (e.g., activation of PGC1α by AMPK, and FHL1 by titin) and context-specific mechanisms (e.g., regulation of Ca2+ sensitivity by titin in HCM patients) that may control genotype-to-phenotype transition in HCM across different species or mutations. We also predicted potential combination drug targets for HCM (e.g., mavacamten plus ROS inhibitors) preventing or reversing HCM phenotype (i.e., hypertrophic growth, apoptosis, and metabolic remodeling) in cardiomyocytes. This study provides new insights into mechanisms linking genotype to phenotype in familial hypertrophic cardiomyopathy and offers a framework for assessing new treatments and exploring variations in HCM experimental models.
PMID:38677172 | DOI:10.1016/j.compbiomed.2024.108499
Short 2'-O-methyl/LNA oligomers as highly-selective inhibitors of miRNA production in vitro and in vivo
Nucleic Acids Res. 2024 Apr 27:gkae284. doi: 10.1093/nar/gkae284. Online ahead of print.
ABSTRACT
MicroRNAs (miRNAs) that share identical or near-identical sequences constitute miRNA families and are predicted to act redundantly. Yet recent evidence suggests that members of the same miRNA family with high sequence similarity might have different roles and that this functional divergence might be rooted in their precursors' sequence. Current knock-down strategies such as antisense oligonucleotides (ASOs) or miRNA sponges cannot distinguish between identical or near identical miRNAs originating from different precursors to allow exploring unique functions of these miRNAs. We here develop a novel strategy based on short 2'-OMe/LNA-modified oligonucleotides to selectively target specific precursor molecules and ablate the production of individual members of miRNA families in vitro and in vivo. Leveraging the highly conserved Xenopus miR-181a family as proof-of-concept, we demonstrate that 2'-OMe/LNA-ASOs targeting the apical region of pre-miRNAs achieve precursor-selective inhibition of mature miRNA-5p production. Furthermore, we extend the applicability of our approach to the human miR-16 family, illustrating its universality in targeting precursors generating identical miRNAs. Overall, our strategy enables efficient manipulation of miRNA expression, offering a powerful tool to dissect the functions of identical or highly similar miRNAs derived from different precursors within miRNA families.
PMID:38676942 | DOI:10.1093/nar/gkae284
Protocol for the isolation of the mouse sympathetic splanchnic-celiac-superior mesenteric ganglion complex
STAR Protoc. 2024 Apr 26;5(2):103036. doi: 10.1016/j.xpro.2024.103036. Online ahead of print.
ABSTRACT
Neurons that originate from pre-vertebral sympathetic ganglia, the splanchnic-celiac-superior mesenteric ganglion complex (SCSMG) in mouse, have important roles in control of organs of the upper abdomen. Here, we present a protocol for the isolation of the mouse sympathetic SCSMG. We describe steps for surgical incision, ganglia isolation, ganglia fine dissection, and whole-mount SCSMG after clearing-enhanced 3D (Ce3D) clearing method and immunohistochemistry. Given the importance of mice in studies of that control, this protocol aims to assist biomedical researchers in the dissection of the mouse SCSMG.
PMID:38676927 | DOI:10.1016/j.xpro.2024.103036
Loss of LPAR6 and CAB39L dysregulates the basal-to-luminal urothelial differentiation program, contributing to bladder carcinogenesis
Cell Rep. 2024 Apr 25;43(5):114146. doi: 10.1016/j.celrep.2024.114146. Online ahead of print.
ABSTRACT
We describe a strategy that combines histologic and molecular mapping that permits interrogation of the chronology of changes associated with cancer development on a whole-organ scale. Using this approach, we present the sequence of alterations around RB1 in the development of bladder cancer. We show that RB1 is not involved in initial expansion of the preneoplastic clone. Instead, we found a set of contiguous genes that we term "forerunner" genes whose silencing is associated with the development of plaque-like field effects initiating carcinogenesis. Specifically, we identified five candidate forerunner genes (ITM2B, LPAR6, MLNR, CAB39L, and ARL11) mapping near RB1. Two of these genes, LPAR6 and CAB39L, are preferentially downregulated in the luminal and basal subtypes of bladder cancer, respectively. Their loss of function dysregulates urothelial differentiation, sensitizing the urothelium to N-butyl-N-(4-hydroxybutyl)nitrosamine-induced cancers, which recapitulate the luminal and basal subtypes of human bladder cancer.
PMID:38676926 | DOI:10.1016/j.celrep.2024.114146
Glutathione: a key modulator of plant defence and metabolism through multiple mechanisms
J Exp Bot. 2024 Apr 27:erae194. doi: 10.1093/jxb/erae194. Online ahead of print.
ABSTRACT
Redox reactions are fundamental to energy conversion in living cells, and also determine and tune responses to the environment. Within this context, the tripeptide glutathione plays numerous roles. As an important antioxidant, glutathione confers redox stability on the cell and also acts an interface between signalling pathways and metabolic reactions that fuel growth and development. It also contributes to the assembly of cell components, biosynthesis of sulphur-containing metabolites, inactivation of potentially deleterious compounds, and control of hormonal signalling intensity. The multiplicity of these roles probably explains why glutathione status has been implicated in influencing plant responses to many different conditions. In particular, there is now a considerable body of evidence that glutathione is a crucial player in governing the outcome of biotic stresses. This review provides an overview of glutathione synthesis, transport, degradation, and redox turnover in plants. It examines the expression of genes associated with these processes during pathogen challenge and related conditions, and considers the diversity of mechanisms by which glutathione can influence protein function and gene expression.
PMID:38676714 | DOI:10.1093/jxb/erae194
Disrupting cell wall integrity impacts endomembrane trafficking to promote secretion over endocytic trafficking
J Exp Bot. 2024 Apr 27:erae195. doi: 10.1093/jxb/erae195. Online ahead of print.
ABSTRACT
The plant cell wall provides a strong yet flexible barrier to protect cells from the external environment. Modifications of the cell wall, either during development or under stress conditions, can induce cell wall integrity responses and ultimately lead to alterations in gene expression, hormone production, and cell wall composition. These changes in cell wall composition presumably require remodelling of the secretory pathway to facilitate synthesis and secretion of cell wall components and cell wall synthesis enzymes from the Golgi apparatus. Here, we used a combination of live-cell confocal imaging and transmission electron microscopy to examine the short-term and constitutive impact of isoxaben, which reduces cellulose biosynthesis, and Driselase, a cocktail of cell-wall-degrading fungal enzymes, on cellular processes during cell wall integrity responses. We show that both treatments altered organelle morphology and triggered rebalancing of the secretory pathway to promote secretion while reducing endocytic trafficking. The actin cytoskeleton was less dynamic following cell wall modification, and organelle movement was reduced. These results demonstrate active remodelling of the endomembrane system and actin cytoskeleton following changes to the cell wall.
PMID:38676707 | DOI:10.1093/jxb/erae195
IUIS 2023: yEFIS workshop on career development and code-switching
Eur J Immunol. 2024 Apr 27:e2451155. doi: 10.1002/eji.202451155. Online ahead of print.
NO ABSTRACT
PMID:38676471 | DOI:10.1002/eji.202451155
The cuticle proteome of a planktonic crustacean
Proteomics. 2024 Apr 27:e2300292. doi: 10.1002/pmic.202300292. Online ahead of print.
ABSTRACT
The cuticles of arthropods provide an interface between the organism and its environment. Thus, the cuticle's structure influences how the organism responds to and interacts with its surroundings. Here, we used label-free quantification proteomics to provide a proteome of the moulted cuticle of the aquatic crustacean Daphnia magna, which has long been a prominent subject of studies on ecology, evolution, and developmental biology. We detected a total of 278 high-confidence proteins. Using protein sequence domain and functional enrichment analyses, we identified chitin-binding structural proteins and chitin-modifying enzymes as the most abundant protein groups in the cuticle proteome. Structural cuticular protein families showed a similar distribution to those found in other arthropods and indicated proteins responsible for the soft and flexible structure of the Daphnia cuticle. Finally, cuticle protein genes were also clustered as tandem gene arrays in the D. magna genome. The cuticle proteome presented here will be a valuable resource to the Daphnia research community, informing genome annotations and investigations on diverse topics such as the genetic basis of interactions with predators and parasites.
PMID:38676470 | DOI:10.1002/pmic.202300292
Autophagy Deregulation in HIV-1-Infected Cells Increases Extracellular Vesicle Release and Contributes to TLR3 Activation
Viruses. 2024 Apr 20;16(4):643. doi: 10.3390/v16040643.
ABSTRACT
Human immunodeficiency virus type 1 (HIV-1) infection can result in HIV-associated neurocognitive disorder (HAND), a spectrum of disorders characterized by neurological impairment and chronic inflammation. Combined antiretroviral therapy (cART) has elicited a marked reduction in the number of individuals diagnosed with HAND. However, there is continual, low-level viral transcription due to the lack of a transcription inhibitor in cART regimens, which results in the accumulation of viral products within infected cells. To alleviate stress, infected cells can release accumulated products, such as TAR RNA, in extracellular vesicles (EVs), which can contribute to pathogenesis in neighboring cells. Here, we demonstrate that cART can contribute to autophagy deregulation in infected cells and increased EV release. The impact of EVs released from HIV-1 infected myeloid cells was found to contribute to CNS pathogenesis, potentially through EV-mediated TLR3 (Toll-like receptor 3) activation, suggesting the need for therapeutics to target this mechanism. Three HIV-1 TAR-binding compounds, 103FA, 111FA, and Ral HCl, were identified that recognize TAR RNA and reduce TLR activation. These data indicate that packaging of viral products into EVs, potentially exacerbated by antiretroviral therapeutics, may induce chronic inflammation of the CNS observed in cART-treated patients, and novel therapeutic strategies may be exploited to mitigate morbidity.
PMID:38675983 | DOI:10.3390/v16040643