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Signal Transduction and Targeted Therapy Apr 2024The translocation of YAP from the cytoplasm to the nucleus is critical for its activation and plays a key role in tumor progression. However, the precise molecular...
The translocation of YAP from the cytoplasm to the nucleus is critical for its activation and plays a key role in tumor progression. However, the precise molecular mechanisms governing the nuclear import of YAP are not fully understood. In this study, we have uncovered a crucial role of SOX9 in the activation of YAP. SOX9 promotes the nuclear translocation of YAP by direct interaction. Importantly, we have identified that the binding between Asp-125 of SOX9 and Arg-124 of YAP is essential for SOX9-YAP interaction and subsequent nuclear entry of YAP. Additionally, we have discovered a novel asymmetrical dimethylation of YAP at Arg-124 (YAP-R124me2a) catalyzed by PRMT1. YAP-R124me2a enhances the interaction between YAP and SOX9 and is associated with poor prognosis in multiple cancers. Furthermore, we disrupted the interaction between SOX9 and YAP using a competitive peptide, S-A1, which mimics an α-helix of SOX9 containing Asp-125. S-A1 significantly inhibits YAP nuclear translocation and effectively suppresses tumor growth. This study provides the first evidence of SOX9 as a pivotal regulator driving YAP nuclear translocation and presents a potential therapeutic strategy for YAP-driven human cancers by targeting SOX9-YAP interaction.
Topics: Humans; YAP-Signaling Proteins; Transcription Factors; Adaptor Proteins, Signal Transducing; Cell Nucleus; SOX9 Transcription Factor; Protein-Arginine N-Methyltransferases; Neoplasms; Active Transport, Cell Nucleus; Mice; Cell Line, Tumor; Animals; Repressor Proteins
PubMed: 38653754
DOI: 10.1038/s41392-024-01805-4 -
Cell Reports May 2024DNA sensing is important for antiviral immunity. The DNA sensor cGAS synthesizes 2'3'-cyclic GMP-AMP (cGAMP), a second messenger that activates STING, which induces...
DNA sensing is important for antiviral immunity. The DNA sensor cGAS synthesizes 2'3'-cyclic GMP-AMP (cGAMP), a second messenger that activates STING, which induces innate immunity. cGAMP not only activates STING in the cell where it is produced but cGAMP also transfers to other cells. Transporters, channels, and pores (including SLC19A1, SLC46A2, P2X7, ABCC1, and volume-regulated anion channels (VRACs)) release cGAMP into the extracellular space and/or import cGAMP. We report that infection with multiple human viruses depletes some of these cGAMP conduits. This includes herpes simplex virus 1 (HSV-1) that targets SLC46A2, P2X7, and the VRAC subunits LRRC8A and LRRC8C for degradation. The HSV-1 protein UL56 is necessary and sufficient for these effects that are mediated at least partially by proteasomal turnover. UL56 thereby inhibits cGAMP uptake via VRAC, SLC46A2, and P2X7. Taken together, HSV-1 antagonizes intercellular cGAMP transfer. We propose that this limits innate immunity by reducing cell-to-cell communication via the immunotransmitter cGAMP.
Topics: Animals; Humans; HEK293 Cells; Herpes Simplex; Herpesvirus 1, Human; Nucleotides, Cyclic; Viral Proteins
PubMed: 38652659
DOI: 10.1016/j.celrep.2024.114122 -
BioRxiv : the Preprint Server For... Apr 2024Human immunodeficiency virus type 1 (HIV-1) capsid, which is the target of the antiviral lenacapavir, protects the viral genome and binds multiple host proteins to...
Human immunodeficiency virus type 1 (HIV-1) capsid, which is the target of the antiviral lenacapavir, protects the viral genome and binds multiple host proteins to influence intracellular trafficking, nuclear import, and integration. Previously, we showed that capsid binding to cleavage and polyadenylation specificity factor 6 (CPSF6) in the cytoplasm is competitively inhibited by cyclophilin A (CypA) binding and regulates capsid trafficking, nuclear import, and infection. Here we determined that a capsid mutant with increased CypA binding affinity had significantly reduced nuclear entry and mislocalized integration. However, disruption of CypA binding to the mutant capsid restored nuclear entry, integration, and infection in a CPSF6-dependent manner. Furthermore, relocalization of CypA expression from the cell cytoplasm to the nucleus failed to restore mutant HIV-1 infection. Our results clarify that sequential binding of CypA and CPSF6 to HIV-1 capsid is required for optimal nuclear entry and integration targeting, informing antiretroviral therapies that contain lenacapavir.
PubMed: 38645162
DOI: 10.1101/2024.04.08.588584 -
Virus Research Jul 2024Although all herpesviruses utilize a highly conserved replication machinery to amplify their viral genomes, different members may have unique strategies to modulate the...
Although all herpesviruses utilize a highly conserved replication machinery to amplify their viral genomes, different members may have unique strategies to modulate the assembly of their replication components. Herein, we characterize the subcellular localization of seven essential replication proteins of varicella-zoster virus (VZV) and show that several viral replication enzymes such as the DNA polymerase subunit ORF28, when expressed alone, are localized in the cytoplasm. The nuclear import of ORF28 can be mediated by the viral DNA polymerase processivity factor ORF16. Besides, ORF16 could markedly enhance the protein abundance of ORF28. Noteworthily, an ORF16 mutant that is defective in nuclear transport still retained the ability to enhance ORF28 abundance. The low abundance of ORF28 in transfected cells was due to its rapid degradation mediated by the ubiquitin-proteasome system. We additionally reveal that radicicol, an inhibitor of the chaperone Hsp90, could disrupt the interaction between ORF16 and ORF28, thereby affecting the nuclear entry and protein abundance of ORF28. Collectively, our findings imply that the cytoplasmic retention and rapid degradation of ORF28 may be a key regulatory mechanism for VZV to prevent untimely viral DNA replication, and suggest that Hsp90 is required for the interaction between ORF16 and ORF28.
Topics: Herpesvirus 3, Human; Humans; Viral Proteins; Virus Replication; Active Transport, Cell Nucleus; DNA-Directed DNA Polymerase; Cell Nucleus; Cytoplasm; Cell Line; DNA Replication
PubMed: 38643859
DOI: 10.1016/j.virusres.2024.199379 -
Nature Cell Biology May 2024Imaging-based methods are widely used for studying the subcellular localization of proteins in living cells. While routine for individual proteins, global monitoring of...
Imaging-based methods are widely used for studying the subcellular localization of proteins in living cells. While routine for individual proteins, global monitoring of protein dynamics following perturbation typically relies on arrayed panels of fluorescently tagged cell lines, limiting throughput and scalability. Here, we describe a strategy that combines high-throughput microscopy, computer vision and machine learning to detect perturbation-induced changes in multicolour tagged visual proteomics cell (vpCell) pools. We use genome-wide and cancer-focused intron-targeting sgRNA libraries to generate vpCell pools and a large, arrayed collection of clones each expressing two different endogenously tagged fluorescent proteins. Individual clones can be identified in vpCell pools by image analysis using the localization patterns and expression level of the tagged proteins as visual barcodes, enabling simultaneous live-cell monitoring of large sets of proteins. To demonstrate broad applicability and scale, we test the effects of antiproliferative compounds on a pool with cancer-related proteins, on which we identify widespread protein localization changes and new inhibitors of the nuclear import/export machinery. The time-resolved characterization of changes in subcellular localization and abundance of proteins upon perturbation in a pooled format highlights the power of the vpCell approach for drug discovery and mechanism-of-action studies.
Topics: Humans; Proteomics; Machine Learning; Microscopy, Fluorescence; Cell Line, Tumor
PubMed: 38641660
DOI: 10.1038/s41556-024-01407-w -
Frontiers in Immunology 2024Interleukin-21 (IL-21) is an immunostimulatory cytokine which belongs to the common gamma-chain family of cytokines. It plays an import role in the development,... (Review)
Review
Interleukin-21 (IL-21) is an immunostimulatory cytokine which belongs to the common gamma-chain family of cytokines. It plays an import role in the development, differentiation, proliferation, and activation of immune cells, in particular T and natural killer (NK) cells. Since its discovery in 2000, IL-21 has been shown to regulate both adaptive and immune responses associates with key role in antiviral and antitumor responses. Recent advances indicate IL-21 as a promising target for cancer treatment and encouraging results were obtained in preclinical studies which investigated the potency of IL-21 alone or in combination with other therapies, including monoclonal antibodies, checkpoint inhibitory molecules, oncolytic virotherapy, and adoptive cell transfer. Furthermore, IL-21 showed antitumor effects in the treatment of patients with advanced cancer, with minimal side effects in several clinical trials. In the present review, we will outline the recent progress in IL-21 research, highlighting the potential of IL-21 based therapy as single agent or in combination with other drugs to enhance cancer treatment efficiency.
Topics: Humans; Neoplasms; Interleukins; Cytokines; Immunotherapy
PubMed: 38638431
DOI: 10.3389/fimmu.2024.1369743 -
Microbial Physiology 2024The gut microbiome is integral to host health, hosting complex interactions between the host and numerous microbial species in the gastrointestinal tract. Key among the... (Review)
Review
BACKGROUND
The gut microbiome is integral to host health, hosting complex interactions between the host and numerous microbial species in the gastrointestinal tract. Key among the molecular mechanisms employed by gut bacteria are transportomes, consisting of diverse transport proteins crucial for bacterial adaptation to the dynamic, nutrient-rich environment of the mammalian gut. These transportomes facilitate the movement of a wide array of molecules, impacting both the host and the microbial community.
SUMMARY
This communication explores the significance of transportomes in gut bacteria, focusing on their role in nutrient acquisition, competitive interactions among microbes, and potential pathogenicity. It delves into the transportomes of key gut bacterial species like E. coli, Salmonella, Bacteroides, Lactobacillus, Clostridia, and Bifidobacterium, examining the functions of predicted transport proteins. The overview synthesizes recent research efforts, highlighting how these transportomes influence host-microbe interactions and contribute to the microbial ecology of the gut.
KEY MESSAGES
Transportomes are vital for the survival and adaptation of bacteria in the gut, enabling the import and export of various nutrients and molecules. The complex interplay of transport proteins not only supports bacterial growth and competition but also has implications for host health, potentially contributing to pathogenic processes. Understanding the pathogenic potential of transportomes in major gut bacterial species provides insights into gut health and disease, offering avenues for future research and therapeutic strategies.
Topics: Gastrointestinal Microbiome; Humans; Bacteria; Animals; Biological Transport; Bacterial Proteins; Host Microbial Interactions; Carrier Proteins; Gastrointestinal Tract
PubMed: 38636461
DOI: 10.1159/000538779 -
Scientific Reports Apr 2024Lung adenocarcinoma (LUAD), a leading cause of cancer-related mortality worldwide, demands a deeper understanding of its molecular mechanisms and the identification of...
Lung adenocarcinoma (LUAD), a leading cause of cancer-related mortality worldwide, demands a deeper understanding of its molecular mechanisms and the identification of reliable biomarkers for better diagnosis and targeted therapy. Leveraging data from the Cancer Genome Atlas (TCGA), the Clinical Proteomic Tumor Analysis Consortium (CPTAC), and the Human Protein Atlas (HPA), we investigated the mRNA and protein expression profiles of TIMM17A and assessed its prognostic significance through Kaplan-Meier survival curves and Cox regression analysis. Through Gene Set Enrichment Analysis, we explored the regulatory mechanisms of TIMM17A in LUAD progression and demonstrated its role in modulating the proliferative capacity of A549 cells, a type of LUAD cell, via in vitro experiments. Our results indicate that TIMM17A is significantly upregulated in LUAD tissues, correlating with clinical staging, lymph node metastasis, overall survival, and progression-free survival, thereby establishing it as a critical independent prognostic factor. The construction of a nomogram model further enhances our ability to predict patient outcomes. Knockdown of TIMM17A inhibited the growth of LUAD cells. The potential of TIMM17A as a biomarker and therapeutic target for LUAD presents a promising pathway for improving patient diagnosis and treatment strategies.
Topics: Humans; Adenocarcinoma of Lung; Lung Neoplasms; Nomograms; Prognosis; Proteomics; Mitochondrial Precursor Protein Import Complex Proteins; Gene Expression Regulation, Neoplastic; Biomarkers, Tumor; A549 Cells
PubMed: 38632467
DOI: 10.1038/s41598-024-59526-1 -
Nature Communications Apr 2024Import of proteins into peroxisomes depends on PEX5, PEX13 and PEX14. By combining biochemical methods and structural biology, we show that the C-terminal SH3 domain of...
Import of proteins into peroxisomes depends on PEX5, PEX13 and PEX14. By combining biochemical methods and structural biology, we show that the C-terminal SH3 domain of PEX13 mediates intramolecular interactions with a proximal FxxxF motif. The SH3 domain also binds WxxxF peptide motifs in the import receptor PEX5, demonstrating evolutionary conservation of such interactions from yeast to human. Strikingly, intramolecular interaction of the PEX13 FxxxF motif regulates binding of PEX5 WxxxF/Y motifs to the PEX13 SH3 domain. Crystal structures reveal how FxxxF and WxxxF/Y motifs are recognized by a non-canonical surface on the SH3 domain. The PEX13 FxxxF motif also mediates binding to PEX14. Surprisingly, the potential PxxP binding surface of the SH3 domain does not recognize PEX14 PxxP motifs, distinct from its yeast ortholog. Our data show that the dynamic network of PEX13 interactions with PEX5 and PEX14, mediated by diaromatic peptide motifs, modulates peroxisomal matrix import.
Topics: Humans; Membrane Proteins; Peptides; Peroxisome-Targeting Signal 1 Receptor; Peroxisomes; Protein Binding; Protein Transport; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; src Homology Domains
PubMed: 38632234
DOI: 10.1038/s41467-024-47605-w -
Biochemical Society Transactions Apr 2024To date, there is no general physical model of the mechanism by which unfolded polypeptide chains with different properties are imported into the mitochondria. At the... (Review)
Review
To date, there is no general physical model of the mechanism by which unfolded polypeptide chains with different properties are imported into the mitochondria. At the molecular level, it is still unclear how transit polypeptides approach, are captured by the protein translocation machinery in the outer mitochondrial membrane, and how they subsequently cross the entropic barrier of a protein translocation pore to enter the intermembrane space. This deficiency has been due to the lack of detailed structural and dynamic information about the membrane pores. In this review, we focus on the recently determined sub-nanometer cryo-EM structures and our current knowledge of the dynamics of the mitochondrial two-pore outer membrane protein translocation machinery (TOM core complex), which provide a starting point for addressing the above questions. Of particular interest are recent discoveries showing that the TOM core complex can act as a mechanosensor, where the pores close as a result of interaction with membrane-proximal structures. We highlight unusual and new correlations between the structural elements of the TOM complexes and their dynamic behavior in the membrane environment.
Topics: Mitochondria; Mitochondrial Membranes; Mitochondrial Precursor Protein Import Complex Proteins; Protein Transport; Cryoelectron Microscopy; Humans; Mitochondrial Membrane Transport Proteins; Models, Molecular; Protein Conformation; Animals
PubMed: 38629718
DOI: 10.1042/BST20231236