Systems Biology
Single-cell transcriptional profiling of hearts during cardiac hypertrophy reveals the role of MAMs in cardiomyocyte subtype switching
Sci Rep. 2023 May 23;13(1):8339. doi: 10.1038/s41598-023-35464-2.
ABSTRACT
Pathological cardiac hypertrophy is the main predecessor of heart failure. Its pathology is sophisticated, and its progression is associated with multiple cellular processes. To explore new therapeutic approaches, more precise examination of cardiomyocyte subtypes and involved biological processes is required in response to hypertrophic stimuli. Mitochondria and the endoplasmic reticulum (ER) are two crucial organelles associated with the progression of cardiac hypertrophy and are connected through junctions known as mitochondria-associated endoplasmic reticulum membranes (MAMs). Although MAM genes are altered in cardiac hypertrophy, the importance of MAMs in cardiac hypertrophy and the expression pattern of MAMs in certain cardiac cell types require a comprehensive analysis. In this study, we analyzed the temporal expression of MAM proteins in the process of cardiac hypertrophy and observed that MAM-related proteins preferentially accumulated in cardiomyocytes at the initial stage of cardiac hypertrophy and underwent a gradual decline, which was synchronized with the proportion of two cardiomyocyte subtypes (CM2 and CM3). Meanwhile, these subtypes went through a functional switch during cardiac hypertrophy. Trajectory analysis suggested that there was a differentiation trajectory of cardiomyocyte subtypes from high to low MAM protein expression. Distinct regulon modules across different cardiomyocyte cell types were revealed by transcriptional regulatory network analysis. Furthermore, scWGCNA revealed that MAM-related genes were clustered into a module that correlated with diabetic cardiomyopathy. Altogether, we identified cardiomyocyte subtype transformation and the potential critical transcription factors involved, which may serve as therapeutic targets in combating cardiac hypertrophy.
PMID:37221368 | DOI:10.1038/s41598-023-35464-2
The roles and implications of RNA m<sup>6</sup>A modification in cancer
Nat Rev Clin Oncol. 2023 May 23. doi: 10.1038/s41571-023-00774-x. Online ahead of print.
ABSTRACT
N6-Methyladenosine (m6A), the most prevalent internal modification in eukaryotic mRNA, has been extensively and increasingly studied over the past decade. Dysregulation of RNA m6A modification and its associated machinery, including writers, erasers and readers, is frequently observed in various cancer types, and the dysregulation profiles might serve as diagnostic, prognostic and/or predictive biomarkers. Dysregulated m6A modifiers have been shown to function as oncoproteins or tumour suppressors with essential roles in cancer initiation, progression, metastasis, metabolism, therapy resistance and immune evasion as well as in cancer stem cell self-renewal and the tumour microenvironment, highlighting the therapeutic potential of targeting the dysregulated m6A machinery for cancer treatment. In this Review, we discuss the mechanisms by which m6A modifiers determine the fate of target RNAs and thereby influence protein expression, molecular pathways and cell phenotypes. We also describe the state-of-the-art methodologies for mapping global m6A epitranscriptomes in cancer. We further summarize discoveries regarding the dysregulation of m6A modifiers and modifications in cancer, their pathological roles, and the underlying molecular mechanisms. Finally, we discuss m6A-related prognostic and predictive molecular biomarkers in cancer as well as the development of small-molecule inhibitors targeting oncogenic m6A modifiers and their activity in preclinical models.
PMID:37221357 | DOI:10.1038/s41571-023-00774-x
Using system biology and bioinformatics to identify the influences of COVID-19 co-infection with influenza virus on COPD
Funct Integr Genomics. 2023 May 24;23(2):175. doi: 10.1007/s10142-023-01091-3.
ABSTRACT
Coronavirus disease 2019 (COVID-19) has speedily increased mortality globally. Although they are risk factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), less is known about the common molecular mechanisms behind COVID-19, influenza virus A (IAV), and chronic obstructive pulmonary disease (COPD). This research used bioinformatics and systems biology to find possible medications for treating COVID-19, IAV, and COPD via identifying differentially expressed genes (DEGs) from gene expression datasets (GSE171110, GSE76925, GSE106986, and GSE185576). A total of 78 DEGs were subjected to functional enrichment, pathway analysis, protein-protein interaction (PPI) network construct, hub gene extraction, and other potentially relevant disorders. Then, DEGs were discovered in networks including transcription factor (TF)-gene connections, protein-drug interactions, and DEG-microRNA (miRNA) coregulatory networks by using NetworkAnalyst. The top 12 hub genes were MPO, MMP9, CD8A, HP, ELANE, CD5, CR2, PLA2G7, PIK3R1, SLAMF1, PEX3, and TNFRSF17. We found that 44 TFs-genes, as well as 118 miRNAs, are directly linked to hub genes. Additionally, we searched the Drug Signatures Database (DSigDB) and identified 10 drugs that could potentially treat COVID-19, IAV, and COPD. Therefore, we evaluated the top 12 hub genes that could be promising DEGs for targeted therapy for SARS-CoV-2 and identified several prospective medications that may benefit COPD patients with COVID-19 and IAV co-infection.
PMID:37221323 | DOI:10.1007/s10142-023-01091-3
Multi-modal deep learning improves grain yield prediction in wheat breeding by fusing genomics and phenomics
Bioinformatics. 2023 May 23:btad336. doi: 10.1093/bioinformatics/btad336. Online ahead of print.
ABSTRACT
MOTIVATION: Developing new crop varieties with superior performance is highly important to ensure robust and sustainable global food security. The speed of variety development is limited by long field cycles and advanced generation selections in plant breeding programs. While methods to predict yield from genotype or phenotype data have been proposed, improved performance and integrated models are needed.
RESULTS: We propose a machine learning model that leverages both genotype and phenotype measurements by fusing genetic variants with multiple data sources collected by unmanned aerial systems. We use a deep multiple instance learning framework with an attention mechanism that sheds light on the importance given to each input during prediction, enhancing interpretability. Our model reaches 0.754 ± 0.024 Pearson correlation coefficient when predicting yield in similar environmental conditions; a 34.8% improvement over the genotype-only linear baseline (0.559 ± 0.050). We further predict yield on new lines in an unseen environment using only genotypes, obtaining a prediction accuracy of 0.386 ± 0.010, a 13.5% improvement over the linear baseline. Our multi-modal deep learning architecture efficiently accounts for plant health and environment, distilling the genetic contribution and providing excellent predictions. Yield prediction algorithms leveraging phenotypic observations during training therefore promise to improve breeding programs, ultimately speeding up delivery of improved varieties.
AVAILABILITY AND IMPLEMENTATION: Available at https://github.com/BorgwardtLab/PheGeMIL (code) and https://doi.org/doi:10.5061/dryad.kprr4xh5p (data).
PMID:37220903 | DOI:10.1093/bioinformatics/btad336
Domains Required for the Interaction of the Central Negative Element FRQ with its Transcriptional Activator WCC within the Core Circadian Clock of Neurospora
J Biol Chem. 2023 May 21:104850. doi: 10.1016/j.jbc.2023.104850. Online ahead of print.
ABSTRACT
In the negative feedback loop composing the Neurospora circadian clock, the core element, FREQUENCY (FRQ) binds with FRH (FRQ-interacting RNA helicase) and Casein Kinase 1 (CK1) to form the FRQ-FRH complex (FFC) which represses its own expression by interacting with and promoting phosphorylation of its transcriptional activators White Collar-1 (WC-1) and WC-2 (together forming the White Collar Complex, WCC). Physical interaction between FFC and WCC is a prerequisite for the repressive phosphorylations, and although the motif on WCC needed for this interaction is known, the reciprocal recognition motif(s) on FRQ remains poorly defined. To address this, we assessed FFC-WCC in a series of frq segmental-deletion mutants, confirming that multiple dispersed regions on FRQ are necessary for its interaction with WCC. Biochemical analysis shows that interaction between FFC and WCC but not within FFC or WCC can be disrupted by high salt, suggesting that electrostatic forces drive the association of the two complexes. As a basic sequence on WC-1 was previously identified as a key motif for WCC-FFC assembly, our mutagenetic analysis targeted negatively charged residues of FRQ leading to identification of three Asp/Glu clusters in FRQ that are indispensable for FFC-WCC formation. Surprisingly, in several frq Asp/Glu-to-Ala mutants that vastly diminish FFC-WCC interaction, the core clock still oscillates robustly with an essentially wild-type (WT) period, indicating that the interaction between the positive and negative elements in the feedback loop is required for the operation of the circadian clock but is not a determinant of the period length.
PMID:37220856 | DOI:10.1016/j.jbc.2023.104850
A Sticky-End Probe Biosensor for Homogeneous Detection of Transcription Factor Binding Activity
SLAS Technol. 2023 May 21:S2472-6303(23)00033-X. doi: 10.1016/j.slast.2023.05.001. Online ahead of print.
ABSTRACT
Transcription factors are essential regulators of various physiological and pathological processes. However, detecting transcription factor-DNA binding activities is often time-consuming and labor-intensive. Homogeneous biosensors that are compatible with mix-and-measure protocols have the potential to simplify the workflow for therapeutic screening and disease diagnostics. In this study, we apply a combined computational-experimental approach to investigate the design of a sticky-end probe biosensor, where the transcription factor-DNA complex stabilizes the fluorescence resonance energy transfer signal of the donor-acceptor pair. We design a sticky-end biosensor for the SOX9 transcription factor based on the consensus sequence and characterize its sensing performance. A systems biology model is also developed to investigate the reaction kinetics and optimize the operating conditions. Taken together, our study provides a conceptual framework for the design and optimization of sticky-end probe biosensors for homogeneous detection of transcription factor-DNA binding activity.
PMID:37220830 | DOI:10.1016/j.slast.2023.05.001
A multi-scale map of protein assemblies in the DNA damage response
Cell Syst. 2023 May 16:S2405-4712(23)00116-3. doi: 10.1016/j.cels.2023.04.007. Online ahead of print.
ABSTRACT
The DNA damage response (DDR) ensures error-free DNA replication and transcription and is disrupted in numerous diseases. An ongoing challenge is to determine the proteins orchestrating DDR and their organization into complexes, including constitutive interactions and those responding to genomic insult. Here, we use multi-conditional network analysis to systematically map DDR assemblies at multiple scales. Affinity purifications of 21 DDR proteins, with/without genotoxin exposure, are combined with multi-omics data to reveal a hierarchical organization of 605 proteins into 109 assemblies. The map captures canonical repair mechanisms and proposes new DDR-associated proteins extending to stress, transport, and chromatin functions. We find that protein assemblies closely align with genetic dependencies in processing specific genotoxins and that proteins in multiple assemblies typically act in multiple genotoxin responses. Follow-up by DDR functional readouts newly implicates 12 assembly members in double-strand-break repair. The DNA damage response assemblies map is available for interactive visualization and query (ccmi.org/ddram/).
PMID:37220749 | DOI:10.1016/j.cels.2023.04.007
Rational Design of Covalent Kinase Inhibitors by an Integrated Computational Workflow (Kin-Cov)
J Med Chem. 2023 May 23. doi: 10.1021/acs.jmedchem.3c00088. Online ahead of print.
ABSTRACT
Covalent kinase inhibitors (CKIs) hold great promise for drug development. However, examples of computationally guided design of CKIs are still scarce. Here, we present an integrated computational workflow (Kin-Cov) for rational design of CKIs. The design of the first covalent leucine-zipper and sterile-α motif kinase (ZAK) inhibitor was presented as an example to showcase the power of computational workflow for CKI design. The two representative compounds, 7 and 8, inhibited ZAK kinase with half-maximal inhibitory concentration (IC50) values of 9.1 and 11.5 nM, respectively. Compound 8 displayed an excellent ZAK target specificity in Kinome profiling against 378 wild-type kinases. Structural biology and cell-based Western blot washout assays validated the irreversible binding characteristics of the compounds. Our study presents a rational approach for the design of CKIs based on the reactivity and accessibility of nucleophilic amino acid residues in a kinase. The workflow is generalizable and can be applied to facilitate CKI-based drug design.
PMID:37220641 | DOI:10.1021/acs.jmedchem.3c00088
Integrating multiomics data accelerates elucidation of plant primary and secondary metabolic pathways
aBIOTECH. 2023 Jan 11;4(1):47-56. doi: 10.1007/s42994-022-00091-4. eCollection 2023 Mar.
ABSTRACT
Plants are the most important sources of food for humans, as well as supplying many ingredients that are of great importance for human health. Developing an understanding of the functional components of plant metabolism has attracted considerable attention. The rapid development of liquid chromatography and gas chromatography, coupled with mass spectrometry, has allowed the detection and characterization of many thousands of metabolites of plant origin. Nowadays, elucidating the detailed biosynthesis and degradation pathways of these metabolites represents a major bottleneck in our understanding. Recently, the decreased cost of genome and transcriptome sequencing rendered it possible to identify the genes involving in metabolic pathways. Here, we review the recent research which integrates metabolomic with different omics methods, to comprehensively identify structural and regulatory genes of the primary and secondary metabolic pathways. Finally, we discuss other novel methods that can accelerate the process of identification of metabolic pathways and, ultimately, identify metabolite function(s).
PMID:37220537 | PMC:PMC10199974 | DOI:10.1007/s42994-022-00091-4
Membrane Ruffling is a Mechanosensor of Extracellular Fluid Viscosity
Nat Phys. 2022 Sep;18(9):1112-1121. doi: 10.1038/s41567-022-01676-y. Epub 2022 Jul 25.
ABSTRACT
Cell behaviour is affected by the physical forces and mechanical properties of the cells and of their microenvironment. The viscosity of extracellular fluid - a component of the cellular microenvironment - can vary by orders of magnitude, but its effect on cell behaviour remains largely unexplored. Using bio-compatible polymers to increase the viscosity of the culture medium, we characterize how viscosity affects cell behaviour. We find that multiple types of adherent cells respond in an unexpected but similar manner to elevated viscosity. In a highly viscous medium, cells double their spread area, exhibit increased focal adhesion formation and turnover, generate significantly greater traction forces, and migrate nearly two times faster. We observe that when cells are immersed in regular medium, these viscosity-dependent responses require an actively ruffling lamellipodium - a dynamic membrane structure at the front of the cell. We present evidence that cells utilize membrane ruffling to sense changes in extracellular fluid viscosity and to trigger adaptive responses.
PMID:37220497 | PMC:PMC10202009 | DOI:10.1038/s41567-022-01676-y
Metabolome plasticity in 241 Arabidopsis thaliana accessions reveals evolutionary cold adaptation processes
Plant Physiol. 2023 May 23:kiad298. doi: 10.1093/plphys/kiad298. Online ahead of print.
ABSTRACT
Acclimation and adaptation of metabolism to a changing environment are key processes for plant survival and reproductive success. In the present study, 241 natural accessions of Arabidopsis (Arabidopsis thaliana) were grown under two different temperature regimes, 16 °C and 6 °C, and growth parameters were recorded, together with metabolite profiles, to investigate the natural genome × environment effects on metabolome variation. The plasticity of metabolism, which was captured by metabolic distance measures, varied considerably between accessions. Both relative growth rates and metabolic distances were predictable by the underlying natural genetic variation of accessions. Applying machine learning methods, climatic variables of the original growth habitats were tested for their predictive power of natural metabolic variation among accessions. We found specifically habitat temperature during the first quarter of the year to be the best predictor of the plasticity of primary metabolism, indicating habitat temperature as the causal driver of evolutionary cold adaptation processes. Analyses of epigenome- and genome-wide associations revealed accession-specific differential DNA-methylation levels as potentially linked to the metabolome and identified FUMARASE2 as strongly associated with cold adaptation in Arabidopsis accessions. These findings were supported by calculations of the biochemical Jacobian matrix based on variance and covariance of metabolomics data, which revealed that growth under low temperatures most substantially affects the accession-specific plasticity of fumarate and sugar metabolism. Our findings indicate that the plasticity of metabolic regulation is predictable from the genome and epigenome and driven evolutionarily by Arabidopsis growth habitats.
PMID:37220420 | DOI:10.1093/plphys/kiad298
Hypoxia extends lifespan and neurological function in a mouse model of aging
PLoS Biol. 2023 May 23;21(5):e3002117. doi: 10.1371/journal.pbio.3002117. eCollection 2023 May.
ABSTRACT
There is widespread interest in identifying interventions that extend healthy lifespan. Chronic continuous hypoxia delays the onset of replicative senescence in cultured cells and extends lifespan in yeast, nematodes, and fruit flies. Here, we asked whether chronic continuous hypoxia is beneficial in mammalian aging. We utilized the Ercc1 Δ/- mouse model of accelerated aging given that these mice are born developmentally normal but exhibit anatomic, physiological, and biochemical features of aging across multiple organs. Importantly, they exhibit a shortened lifespan that is extended by dietary restriction, the most potent aging intervention across many organisms. We report that chronic continuous 11% oxygen commenced at 4 weeks of age extends lifespan by 50% and delays the onset of neurological debility in Ercc1 Δ/- mice. Chronic continuous hypoxia did not impact food intake and did not significantly affect markers of DNA damage or senescence, suggesting that hypoxia did not simply alleviate the proximal effects of the Ercc1 mutation, but rather acted downstream via unknown mechanisms. To the best of our knowledge, this is the first study to demonstrate that "oxygen restriction" can extend lifespan in a mammalian model of aging.
PMID:37220109 | DOI:10.1371/journal.pbio.3002117
Differentiation and single-cell RNA-seq analyses of human pluripotent-stem-cell-derived renal organoids
STAR Protoc. 2023 May 22;4(2):102314. doi: 10.1016/j.xpro.2023.102314. Online ahead of print.
ABSTRACT
Here, we present a protocol for the maintenance and differentiation of human pluripotent stem cells into renal organoids. We describe steps for using a series of readily made differentiation media, multiplexed sample single-cell RNA-seq analysis, quality control, and validation of organoids using immunofluorescence. This provides a rapid and reproducible model of human kidney development and renal disease modeling. Finally, we detail genome engineering using CRISPR-Cas9 homology-directed repair for the generation of renal disease models. For complete details on the use and execution of this protocol, please refer to Pietrobon et al.1.
PMID:37220001 | DOI:10.1016/j.xpro.2023.102314
The latest advances in high content screening in microfluidic devices
Expert Opin Drug Discov. 2023 May 23:1-15. doi: 10.1080/17460441.2023.2216013. Online ahead of print.
ABSTRACT
INTRODUCTION: High content screening (HCS) is an important tool for drug screening. However, the potential of HCS in the field of drug screening and synthetic biology is limited by traditional culture platforms that use multi-well plates, which have several disadvantages. Recently, microfluidic devices have gradually been applied in HCS, which significantly reduces experimental costs, increases assay throughput, and improves the accuracy of drug screening.
AREAS COVERED: This review provides an overview of microfluidic devices for high-content screening in drug discovery platforms, including droplet, microarray, and organs-on-chip technologies.
EXPERT OPINION: HCS is a promising technology increasingly adopted by the pharmaceutical industry as well as academic researchers for drug discovery and screening. In particular, microfluidic-based HCS shows unique advantages, and microfluidics technology has promoted significant advancements and broader usage and applicability of HCS in drug discovery. With the integration of stem cell, gene editing technology, and other biological technologies, microfluidics-based HCS will expand the application scope of personalized disease and drug screening models. The authors anticipate rapid developments in this field, with microfluidic-based approaches becoming increasingly important in HCS applications.
PMID:37219918 | DOI:10.1080/17460441.2023.2216013
Arabidopsis thaliana B-GATA factors repress starch synthesis and gravitropic growth responses
New Phytol. 2023 May 23. doi: 10.1111/nph.18992. Online ahead of print.
ABSTRACT
Plants perceive the direction of gravity during skotomorphogenic growth, and of gravity and light during photomorphogenic growth. Gravity perception occurs through the sedimentation of starch granules in shoot endodermal and root columella cells. In this study, we demonstrate that the Arabidopsis thaliana GATA factors GNC (GATA, NITRATE-INDUCIBLE, CARBON METABOLISM-INVOLVED) and GNL/CGA1 (GNC-LIKE/CYTOKININ-RESPONSIVE GATA1) repress starch granule growth and amyloplast differentiation in endodermal cells. In our comprehensive study, we analysed gravitropic responses in the shoot, root and hypocotyl. We performed an RNA-seq analysis, used advanced microscopy techniques to examine starch granule size, number and morphology and quantified transitory starch degradation patterns. Using transmission electron microscopy, we examined amyloplast development. Our results indicate that the altered gravitropic responses in hypocotyls, shoots and roots of gnc gnl mutants and GNL overexpressors are due to the differential accumulation of starch granules observed in the GATA genotypes. At the whole-plant level, GNC and GNL play a more complex role in starch synthesis, degradation and starch granule initiation. Our findings suggest that the light-regulated GNC and GNL help balance phototropic and gravitropic growth responses after the transition from skotomorphogenesis to photomorphogenesis by repressing the growth of starch granules.
PMID:37219878 | DOI:10.1111/nph.18992
SnRK1 inhibits anthocyanin biosynthesis through both transcriptional regulation and direct phosphorylation and dissociation of the MYB/bHLH/TTG1 MBW complex
Plant J. 2023 May 23. doi: 10.1111/tpj.16312. Online ahead of print.
ABSTRACT
Plants have evolved an extensive specialized secondary metabolism. The colorful flavonoid anthocyanins, for example, not only stimulate flower pollination and seed dispersal but also protect different tissues against high light, UV- and oxidative stress. Their biosynthesis is highly regulated by environmental and developmental cues and induced by high sucrose levels. Expression of the biosynthetic enzymes involved is controlled by a transcriptional MBW complex, comprising (R2R3) MYB- and bHLH-type transcription factors (TF) and the WD40 repeat protein TTG1. Anthocyanin biosynthesis is obviously useful but also carbon- and energy-intensive and non-vital. Consistently, the SnRK1 protein kinase, a metabolic sensor activated in carbon- and energy-depleting stress conditions, represses anthocyanin biosynthesis. Here we show that Arabidopsis SnRK1 represses MBW complex activity both at the transcriptional and post-translational level. In addition to repressing expression of the key transcription factor MYB75/PAP1, SnRK1 activity triggers MBW complex dissociation, associated with loss of target promoter binding, MYB75 protein degradation and nuclear export of TTG1. We also provide evidence for direct interaction with and phosphorylation of multiple MBW complex proteins. These results indicate that repression of expensive anthocyanin biosynthesis is an important strategy to save energy and redirect carbon flow to more essential processes for survival in metabolic stress conditions.
PMID:37219821 | DOI:10.1111/tpj.16312
Antibacterial, bacteriolytic, and antibiofilm activities of the essential oil of temu giring (<em>Curcuma heyneana</em> Val.) against foodborne pathogens
Food Sci Technol Int. 2023 May 22:10820132231178060. doi: 10.1177/10820132231178060. Online ahead of print.
ABSTRACT
Foodborne pathogens may cause foodborne illness, which is among the major health problems worldwide. Since the therapeutic options for the treatment of the disease are becoming limited as a result of antibacterial resistance, there is an increasing interest to search for new alternatives of antibacterial. Bioactive essential oils from Curcuma sp become potential sources of novel antibacterial substances. The antibacterial activity of Curcuma heyneana essential oil (CHEO) was evaluated against Escherichia coli, Salmonella typhi, Shigella sonnei, and Bacillus cereus. The principal constituents of CHEO are ar-turmerone, β-turmerone, α-zingiberene, α-terpinolene, 1,8-cineole, and camphor. CHEO exhibited the strongest antibacterial activity against E. coli with a MIC of 3.9 µg/mL, which is comparable to that of tetracycline. The combination of CHEO (0.97 µg/mL) and tetracycline (0.48 µg/mL) produced a synergistic effect with a FICI of 0.37. Time-kill assay confirmed that CHEO enhanced the activity of tetracycline. The mixture disrupted membrane permeability of E. coli and induced cell death. CHEO at MIC of 3.9 and 6.8 µg/mL significantly reduced the formation of biofilm in E. coli. The findings suggest that CHEO has the potential to be an alternative source of antibacterial agents against foodborne pathogens, particularly E. coli.
PMID:37218156 | DOI:10.1177/10820132231178060
Intrinsic suppression of type I interferon production underlies the therapeutic efficacy of IL-15-producing natural killer cells in B-cell acute lymphoblastic leukemia
J Immunother Cancer. 2023 May;11(5):e006649. doi: 10.1136/jitc-2022-006649.
ABSTRACT
BACKGROUND: Type I interferons (IFN-Is), secreted by hematopoietic cells, drive immune surveillance of solid tumors. However, the mechanisms of suppression of IFN-I-driven immune responses in hematopoietic malignancies including B-cell acute lymphoblastic leukemia (B-ALL) are unknown.
METHODS: Using high-dimensional cytometry, we delineate the defects in IFN-I production and IFN-I-driven immune responses in high-grade primary human and mouse B-ALLs. We develop natural killer (NK) cells as therapies to counter the intrinsic suppression of IFN-I production in B-ALL.
RESULTS: We find that high expression of IFN-I signaling genes predicts favorable clinical outcome in patients with B-ALL, underscoring the importance of the IFN-I pathway in this malignancy. We show that human and mouse B-ALL microenvironments harbor an intrinsic defect in paracrine (plasmacytoid dendritic cell) and/or autocrine (B-cell) IFN-I production and IFN-I-driven immune responses. Reduced IFN-I production is sufficient for suppressing the immune system and promoting leukemia development in mice prone to MYC-driven B-ALL. Among anti-leukemia immune subsets, suppression of IFN-I production most markedly lowers the transcription of IL-15 and reduces NK-cell number and effector maturation in B-ALL microenvironments. Adoptive transfer of healthy NK cells significantly prolongs survival of overt ALL-bearing transgenic mice. Administration of IFN-Is to B-ALL-prone mice reduces leukemia progression and increases the frequencies of total NK and NK-cell effectors in circulation. Ex vivo treatment of malignant and non-malignant immune cells in primary mouse B-ALL microenvironments with IFN-Is fully restores proximal IFN-I signaling and partially restores IL-15 production. In B-ALL patients, the suppression of IL-15 is the most severe in difficult-to-treat subtypes with MYC overexpression. MYC overexpression promotes sensitivity of B-ALL to NK cell-mediated killing. To counter the suppressed IFN-I-induced IL-15 production in MYChigh human B-ALL, we CRISPRa-engineered a novel human NK-cell line that secretes IL-15. CRISPRa IL-15-secreting human NK cells kill high-grade human B-ALL in vitro and block leukemia progression in vivo more effectively than NK cells that do not produce IL-15.
CONCLUSION: We find that restoration of the intrinsically suppressed IFN-I production in B-ALL underlies the therapeutic efficacy of IL-15-producing NK cells and that such NK cells represent an attractive therapeutic solution for the problem of drugging MYC in high-grade B-ALL.
PMID:37217248 | DOI:10.1136/jitc-2022-006649
BRK confers tamoxifen-resistance in breast cancer via regulation of tyrosine phosphorylation of CDK1
Cell Signal. 2023 May 20:110723. doi: 10.1016/j.cellsig.2023.110723. Online ahead of print.
ABSTRACT
Tamoxifen (Tam) has been the first-line therapy for estrogen receptor-positive breast cancer since its FDA-approval in 1998. Tam-resistance, however, presents a challenge and the mechanisms that drive it have yet to be fully elucidated. The non-receptor tyrosine kinase BRK/PTK6 is a promising candidate as previous research has shown that BRK knockdown resensitizes Tam-resistant breast cancer cells to the drug. However, the specific mechanisms that drive its importance to resistance remain to be investigated. Here, we investigate the role and mechanism of action of BRK in Tam-resistant (TamR), ER+, and T47D breast cancer cells using phosphopeptide enrichment and high throughput phopshoproteomics analysis. We conducted BRK-specific shRNA knockdown in TamR T47D cells and compared phosphopeptides identified in these cells with their Tam-resistant counterpart and parental, Tam-sensitive cells (Par). A total of 6492 STY phosphosites were identified. Of these sites, 3739 high-confidence pST sites and 118 high-confidence pY sites were analyzed for significant changes in phosphorylation levels to identify pathways that were differentially regulated in TamR versus Par and to investigate changes in these pathways when BRK is knocked down in TamR. We observed and validated increased CDK1 phosphorylation at Y15 in TamR cells compared to BRK-depleted TamR cells. Our data suggest that BRK is a potential Y15-directed CDK1 regulatory kinase in Tam-resistant breast cancer.
PMID:37216999 | DOI:10.1016/j.cellsig.2023.110723
Genomic Insights into Adaptation to Karst Limestone and Incipient Speciation in East Asian Platycarya spp. (Juglandaceae)
Mol Biol Evol. 2023 May 22:msad121. doi: 10.1093/molbev/msad121. Online ahead of print.
ABSTRACT
When challenged by similar environmental conditions, phylogenetically distant taxa often independently evolve similar traits (convergent evolution). Meanwhile, adaptation to extreme habitats might lead to divergence between taxa that are otherwise closely related. These processes have long existed in the conceptual sphere, yet molecular evidence, especially for woody perennials, is scarce. The karst endemic Platycarya longipes, and its only congeneric species, P. strobilacea, which is widely distributed in the mountains in East Asia, provide an ideal model for examining the molecular basis of both convergent evolution and speciation. Using chromosome-level genome assemblies of both species, and whole genome resequencing data from 207 individuals spanning their entire distribution range, we demonstrate that P. longipes and P. strobilacea form two species-specific clades, which diverged around 2.09 million years ago. We find an excess of genomic regions exhibiting extreme interspecific differentiation, potentially due to long-term selection in P. longipes, likely contributing to the incipient speciation of the genus Platycarya. Interestingly, our results unveil underlying karst adaptation in both copies of the calcium influx channel gene TPC1 in P. longipes. TPC1 has previously been identified as a selective target in certain karst-endemic herbs, indicating a convergent adaptation to high calcium stress among karst-endemic species. Our study reveals the genic convergence of TPC1 among karst endemics, and the driving forces underneath the incipient speciation of the two Platycarya lineages.
PMID:37216901 | DOI:10.1093/molbev/msad121