Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Lysosomes”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2026

A CRISPR-Cas9 screen identifies LAPTM4A (lysosomal protein transmembrane 4 alpha) as a key host barrier against PRRSV infection.

Porcine reproductive and respiratory syndrome virus (PRRSV) manipulates host intracellular processes, particularly macroautophagy/autophagy and lysosomal function, to facilitate its replication and spread. However, the precise host factors and molecular mechanisms by which PRRSV remodels the autophagy-lysosome axis remain poorly defined. Here, we performed a CRISPR-Cas9 knockout screen targeting 1,332 genes involved in protein degradation, metabolism, and vesicular trafficking, and identified LAPTM4A (lysosomal protein transmembrane 4 alpha) as a critical antiviral factor involved in the lysosomal pathway. A yeast two-hybrid screen identified LAPTM4A as an interactor of PRRSV GP5 (glycoprotein 5). Mechanistically, GP5 recruits the E3 ubiquitin ligase NEDD4 and the autophagy receptor SQSTM1/p62 to promote K63-linked polyubiquitination of LAPTM4A, leading to its autophagic degradation. This selective degradation activates the AMPK-ULK1-MAP1LC3/LC3 signaling cascade, initiating autophagy while facilitating MTOR-lysosome colocalization, thereby suppressing TFEB nuclear translocation and transcription of lysosome-related genes. The resulting incomplete autophagic flux enhances viral replication. Additionally, in terms of host defense, LAPTM4A maintains lysosomal homeostasis by restraining excessive autophagy through AMPK-ULK1-LC3 signaling and promoting TFEB-dependent lysosomal gene expression by impairing the binding of RPTOR/raptor to MTOR, thus providing broad antiviral protection against multiple RNA viruses. Collectively, our findings identify LAPTM4A as a central regulator of lysosome-autophagy homeostasis and reveal a viral strategy that dismantles this defense axis to facilitate infection.Abbreviations: ATG5: autophagy related 5; AMPK: adenosine 5'-monophosphate (AMP)-activated protein kinase; Baf A1: bafilomycin A1; CHX: cycloheximide; Co-IP: co-immunoprecipitation; DMVT library: protein degradation, metabolism, and vesicular trafficking library; LAPTM4A: lysosomal protein transmembrane 4 alpha; MAGeCK: model-based analysis of genome-wide CRISPR-Cas9 knockout; MOI: multiplicity of infection; MTOR: mechanistic target of rapamycin kinase; NC: negative control; PAMs: porcine alveolar macrophages; PRKAA/AMPKα: protein kinase AMP-activated catalytic subunit alpha; PRRSV: porcine reproductive and respiratory syndrome virus; qRT-PCR: quantitative real-time PCR; siRNA: small interfering RNA; SQSTM1/p62: sequestosome 1; TCID50: 50% tissue culture infective dose; TFEB: transcription factor EB; Ub: ubiquitin; ULK1: unc-51 like autophagy activating kinase 1; WT: wild type.

Animals↗
PubMed2024

Proteomic Characterization of Ubiquitin Carboxyl-Terminal Hydrolase 19 Deficient Cells Reveals a Role for USP19 in the Secretion of Lysosomal Proteins.

Ubiquitin carboxyl-terminal hydrolase 19 (USP19) is a unique deubiquitinase, characterized by multiple variants generated by alternative splicing. Several variants bear a C-terminal transmembrane domain that anchors them to the endoplasmic reticulum. Other than regulating protein stability by preventing proteasome degradation, USP19 has been reported to rescue substrates from endoplasmic reticulum-associated protein degradation in a catalytic-independent manner, promote autophagy, and address proteins to lysosomal degradation via endosomal microautophagy. USP19 has recently emerged as the protein responsible for the unconventional secretion of misfolded proteins including Parkinson's disease-associated protein α-synuclein. Despite mounting evidence that USP19 plays crucial roles in several biological processes, the underlying mechanisms are unclear due to lack of information on the physiological substrates of USP19. Herein, we used high-resolution quantitative proteomics to analyze changes in the secretome and cell proteome induced by the loss of USP19 to identify proteins whose secretion or turnover is regulated by USP19. We found that ablation of USP19 induced significant proteomic alterations both in and out of the cell. Loss of USP19 impaired the release of several lysosomal proteins, including legumain (LGMN) and several cathepsins. In order to understand the underlaying mechanism, we dissected the USP19-regulated secretion of LGMN in several cell types. We found that LGMN was not a deubiquitinase substrate of USP19 and that its USP19-dependent release did not require their direct interaction. LGMN secretion occurred by a mechanism that involved the Golgi apparatus, autophagosome formation, and lysosome function. This mechanism resembled the recently described "lysosomal exocytosis," by which lysosomal hydrolases are secreted, when ubiquitination of p62 is increased in cells lacking deubiquitinases such as USP15 and USP17. In conclusion, our proteomic characterization of USP19 has identified a collection of proteins in the secretome and within the cell that are regulated by USP19, which link USP19 to the secretion of lysosomal proteins, including LGMN.

Humans↗
PubMed2025

TCF25 serves as a nutrient sensor to orchestrate metabolic adaptation and cell death by enhancing lysosomal acidification under glucose starvation.

Cells adapt to nutrient limitation by activating catabolic and inhibiting anabolic pathways, yet prolonged stress may lead to cell death. How cells orchestrate metabolic adaptation and cell death to nutrient stress is poorly understood. We conduct a genome-wide CRISPR-Cas9 screen to identify regulators in glucose-starvation-induced cell death and find a group of genes in lysosomal pathway is enriched following glucose starvation. We focus on one candidate gene, Transcriptional Factor 25 (TCF25). We find TCF25 enhances lysosomal acidification by targeting V-ATPase, promoting autophagy and ATP generation under glucose starvation. However, prolonged glucose starvation constitutively activates ferritinophagy via TCF25, increasing lysosomal membrane permeability (LMP) and leading to lysosome-dependent cell death (LDCD). Knocking out TCF25 or V-ATPase components prevents cell death. Furthermore, TCF25 deficiency protects mice from hepatic ischemia-reperfusion injury. Our findings identify TCF25 as a crucial nutrient sensor that regulates lysosomal activity, offering potential therapeutic targets for metabolic and ischemic disorders.

Lysosomes↗
PubMed2026

Neurodegeneration risk variants promote lysosomal TMEM106B fibril accumulation.

Variants in TMEM106B and GRN, which encode lysosomal proteins, interact through unknown mechanisms to increase the risk of age-related cognitive decline and neurodegeneration. Here, we show that these variants converge on a single molecular intermediate: the cleaved intra-lysosomal fibril core of TMEM106B, a precursor to amyloid fibrils that accumulate in the aging brain. A protein-coding TMEM106B risk variant (p.T185) drives fibril core accumulation by impairing its degradation and GRN risk variants amplify this effect. Mice over-expressing the fibril core develop hallmarks of neurodegeneration, and cryo-electron tomography reveals intra-lysosomal fibrils in cultured neurons, mice, and diseased human brain. In GRN-mutation carriers, in whom fibril burden is greatest, fibrils extrude through ruptured lysosomal membranes. These findings identify intra-lysosomal TMEM106B fibrillization as a convergent neurodegeneration mechanism and potential therapeutic target.

Journal Article↗
PubMed2026

Intra-locus coeruleus LPS administration induces anxiety-like behavior, thermal hyperalgesia, and striatal lysosomal alterations: Relevance to Parkinson's disease.

According to Braak's staging hypothesis, Parkinson's disease (PD) pathology may originate in extranigral regions, including the locus coeruleus (LC). In parallel, PD has been associated with lysosomal dysfunction. Here, we investigated whether intra-LC lipopolysaccharide (LPS) injection may produce behavioral alterations and lysosomal protein changes in the striatum and prefrontal cortex (PFC), regions critically implicated in PD pathology. Adult male Wistar rats received unilateral injections of saline or LPS (10 µg/2 µL) into the LC or striatum and were assessed for anxiety-like behavior, thermal hyperalgesia, and motor coordination. A separate cohort was sacrificed 15 days post-injection to assess lysosomal proteins (cathepsin D, β-glucocerebrosidase, Lysosomal Associated Membrane Protein 2 (LAMP2)) and α-synuclein (α-Syn). Intra-LC LPS induced anxiety-like behavior, reflected by reduced time spent in the center of the open field, and thermal hyperalgesia, as shown by shortened tail-flick latency, whereas intra-striatal LPS impaired locomotion and motor coordination, evidenced by reduced line crossings and decreased rotarod performance. Intra-LC but not intra-striatal LPS reduced LAMP2 levels in the striatum, while all other markers remained unchanged in both regions. These findings provide experimental support for Braak's hypothesis.

Animals↗
PubMed2024

Membrane-bound O-acyltransferase 7 (MBOAT7) shapes lysosomal lipid homeostasis and function to control alcohol-associated liver injury.

Recent genome-wide association studies (GWAS) have identified a link between single-nucleotide polymorphisms (SNPs) near the MBOAT7 gene and advanced liver diseases. Specifically, the common MBOAT7 variant (rs641738) associated with reduced MBOAT7 expression is implicated in non-alcoholic fatty liver disease (NAFLD), alcohol-associated liver disease (ALD), and liver fibrosis. However, the precise mechanism underlying MBOAT7-driven liver disease progression remains elusive. Previously, we identified MBOAT7-driven acylation of lysophosphatidylinositol lipids as key mechanism suppressing the progression of NAFLD (Gwag et al., 2019). Here, we show that MBOAT7 loss of function promotes ALD via reorganization of lysosomal lipid homeostasis. Circulating levels of MBOAT7 metabolic products are significantly reduced in heavy drinkers compared to healthy controls. Hepatocyte- (Mboat7-HSKO), but not myeloid-specific (Mboat7-MSKO), deletion of Mboat7 exacerbates ethanol-induced liver injury. Lipidomic profiling reveals a reorganization of the hepatic lipidome in Mboat7-HSKO mice, characterized by increased endosomal/lysosomal lipids. Ethanol-exposed Mboat7-HSKO mice exhibit dysregulated autophagic flux and lysosomal biogenesis, associated with impaired transcription factor EB-mediated lysosomal biogenesis and autophagosome accumulation. This study provides mechanistic insights into how MBOAT7 influences ALD progression through dysregulation of lysosomal biogenesis and autophagic flux, highlighting hepatocyte-specific MBOAT7 loss as a key driver of ethanol-induced liver injury.

Animals↗
PubMed2026

A human lysosomal storage disorder toolkit for decoding proteome landscapes in cortical-like and dopaminergic-like induced neurons.

Lysosomes maintain cellular homeostasis by degrading proteins delivered via endocytosis and autophagy and by recycling building blocks for organelle biogenesis. Lysosomal storage disorders (LSDs) comprise a group of diseases affecting diverse lysosomal functions. To facilitate molecular phenotyping across diverse LSD gene classes, we are developing a library of human embryonic stem cells engineered to lack individual LSD genes as a resource for the field. Here, we report our initial stem cell toolkit lacking one of 23 LSD genes, including the majority of genes associated with sphingolipidoses and neuronal ceroid lipofuscinoses, and its use in the generation of a proteomic resource for induced cortical-like and midbrain dopaminergic-like neurons. In-depth abundance and correlation profiling across organelles and suborganelle components revealed potential vulnerabilities that reflect distinct patterns of proteome alterations across both genotypes and neuronal cell types. We characterize alterations in the mitochondrial proteome associated with GBA1 and ASAH1 deficiency and identify synaptic and mitochondrial defects in ASAH1-/- induced neurons that correlate with defects in neuronal firing rates. Moreover, we developed an informatic pipeline for proteome-wide identification of individual protein-protein interactions and protein complexes that may be disrupted as a result of LSD gene deficiency. Finally, we visualized structural alterations of ASAH1-deficient endolysosomes in situ using cryoelectron tomography, revealing swollen organelles that were largely devoid of dense internal membranes characteristic of wild-type cells, but containing numerous intralumenal vesicle compartments. This toolkit and associated proteomic landscapes provide a resource for defining molecular signatures associated with LSD gene dysfunction and organelle vulnerability.

Humans↗
PubMed2026

Machine learning-based integration develops a novel lysosome-related prognostic signature associated with prognosis and immune infiltration landscape in acute myeloid leukemia.

BACKGROUND: Lysosomes are essential for intracellular degradation and recycling, and changes in their function significantly contribute to tumor growth. Nonetheless, the exact role of lysosome-related genes (LRGs) in the pathogenesis of acute myeloid leukemia (AML) is still inadequately comprehended. METHODS: Differentially expressed LRGs (DE-LRGs) between AML and control groups were identified using AML-related data extracted from the Gene Expression Omnibus (GEO). The LRGs-related prognostic genes were identified and the risk model was established using univariate COX regression analysis and machine learning algorithms, based on the data obtained from The Cancer Genome Atlas (TCGA). Subsequently, we performed comprehensive analyses regarding clinical features, functional pathways, immune microenvironment, and chemotherapeutic drugs sensitivity between the high- and low-risk groups. Reverse transcription Quantitative polymerase chain reaction (RT-qPCR) and western blot were adopted to validate the expression of prognostic genes in human bone marrow-derived cell line HS-27 A and human AML cell line MOLM-13. RESULTS: Through comprehensive analysis, a risk model was developed utilizing ten LRGs (ATP6V0E2, CALCRL, TMEM165, GZMB, HCK, TCIRG1, CD1D, GPRASP1, ABCA1, and NAGA), and this model was further validated using GEO datasets. Significant differences in clinical characteristics, functional pathways, immune microenvironment characteristics, and chemotherapeutic drug sensitivity were observed between the two risk groups In vitro validation experiment illustrated that the expression trends of ATP6V0E2, TMEM165, and ABCA1 were consistent with our bioinformatics analysis. CONCLUSION: Our study demonstrates that lysosome-associated signature might forecast the prognosis of AML patients and offer guidance for subsequent immunotherapy and chemotherapy strategies.

Acute myeloid leukemia↗
PubMed2025

MAPL regulates gasdermin-mediated release of mtDNA from lysosomes to drive pyroptotic cell death.

Mitochondrial control of cell death is of central importance to disease mechanisms from cancer to neurodegeneration. Mitochondrial anchored protein ligase (MAPL) is an outer mitochondrial membrane small ubiquitin-like modifier ligase that is a key determinant of cell survival, yet how MAPL controls the fate of this process remains unclear. Combining genome-wide functional genetic screening and cell biological approaches, we found that MAPL induces pyroptosis through an inflammatory pathway involving mitochondria and lysosomes. MAPL overexpression promotes mitochondrial DNA trafficking in mitochondrial-derived vesicles to lysosomes, which are permeabilized in a process requiring gasdermin pores. This triggers the release of mtDNA into the cytosol, activating the DNA sensor cGAS, required for cell death. Additionally, multiple Parkinson's disease-related genes, including VPS35 and LRRK2, also regulate MAPL-induced pyroptosis. Notably, depletion of MAPL, LRRK2 or VPS35 inhibited inflammatory cell death in primary macrophages, placing MAPL and the mitochondria-lysosome pathway at the nexus of immune signalling and cell death.

Lysosomes↗
PubMed2025

Inhibition of autophagy-lysosomal function exacerbates microglial and monocyte lipid metabolism reprograming and dysfunction after brain injury.

CNS has an overall higher level of lipids than all tissues except adipose and contains up to 25% of total body cholesterol. Recent data demonstrate a complex crosstalk between lipid metabolism and inflammation, suggesting potential contribution of the lipid-rich brain environment to neuroinflammation. While recent data support the importance of brain lipid environment to inflammatory changes observed in age related chronic neurodegenerative diseases, in vivo interactions between lipid environment, lipid metabolism and neuroinflammation in acute brain disease and injury remain poorly understood. Here we utilize a mouse model of traumatic brain injury (TBI) to demonstrate that acute neurotrauma leads to widespread lipid metabolism reprograming in all microglial and brain associated and infiltrating monocyte populations. Additionally, we identify unique microglial and monocyte populations with higher degree of lipid metabolism reprograming and pronounced accumulation of neutral storage lipids, including cholesteryl esters and triglycerides. These lipids accumulate not only in lipid droplets but also in the microglial and monocyte lysosomes and are associated with lysosomal dysfunction and inhibition of autophagy after TBI. Our data indicate that lipid accumulation in these cells is the result of altered lipid handling rather than lipid synthesis and is triggered by phagocytosis of lipid-rich myelin debris generated after TBI. Finally, we use mice with autophagy defects in microglia and monocytes to demonstrate that further inhibition of autophagy leads to more pronounced lipid metabolism reprograming and exacerbated cellular lipid accumulation. Our data suggest a pathological feedback loop, where lipid phagocytosis causes inhibition of autophagy-lysosomal function, which in turn exacerbates cellular lipid retention, reprograming and inflammation.

Journal Article↗
PubMed2025

Decorin Evokes a Pro-lysosomal Pathway in Lymphatic Endothelial Cells.

The lymphatic system is critical to the body's immune and circulatory system, and lymphangiogenesis, the development of new lymphatic vessels from pre-existing ones is a significant process capitalized upon by cancer during tumorigenesis. Decorin is a small leucine-rich proteoglycan which we have previously shown to be anti-tumorigenic and a suppressor of lymphangiogenesis. We have also shown that decorin exercises its anticancer properties through its ability to evoke autophagy. Through a comprehensive and unbiased proteomic analysis, we explored the implications of decorin exposure on protein expression within mouse lymphatic endothelial cells. We discovered that decorin enriches several protein pathways, notably proteasomal degradation and lysosomal pathways. Several proteins within these pathways such as lysosome associated membrane protein 1 (Lamp1) and Neural precursor cell expressed developmentally downregulated protein 8 (Nedd8) were differentially regulated following decorin treatment. These proteins and their functional pathways should be considered therapeutic targets and emerge as candidates for further exploration within the context of decorin and cancer suppression.

Journal Article↗
PubMed2026

Biologic Therapies for Alleviating Neurodegeneration in Lysosomal Storage Diseases.

Lysosomal storage diseases (LSDs) are a group of rare inherited metabolic disorders characterized by lysosomal dysfunction and progressive accumulation of undegraded substrates, leading to multisystem involvement and, in many cases, severe neurodegeneration. Because the blood-brain barrier (BBB) restricts central nervous system (CNS) access for most therapeutic modalities, neurological manifestations remain the major unmet need across LSDs. In this review, we summarize current and emerging strategies aimed at correcting CNS pathology, including enzyme replacement therapy (ERT), adeno-associated virus (AAV)-mediated gene therapy, allogeneic hematopoietic stem cell transplantation (HSCT), and autologous HSCT with gene-modified hematopoietic stem cells. While ERT provides limited CNS benefits and allogeneic HSCT mitigates neurodegeneration only partially, their overall impact on CNS outcomes remains restricted. Newer approaches, such as BBB-shuttling ERTs, CNS-tropic AAV capsids, and genetically modified autologous hematopoietic stem and progenitor cells capable of sustained supraphysiological enzyme production, offer promising avenues for enhanced CNS delivery and cross-correction. Together, these advances underscore a shift toward integrated therapeutic strategies that combine systemic and CNS-directed interventions, with the potential to transform outcomes for patients with LSDs and other neurodegenerative disorders amenable to cross-correction.

Journal Article↗
PubMed2025

STING inhibits LINE-1 retrotransposition through sorting ORF1p to lysosomes for degradation.

The cyclic dinucleotide sensor stimulator of interferon (IFN) genes (STING) is known for its critical role in interferon and inflammatory responses. In addition, STING also has functions independent of interferon induction. In this study, we report that STING restricts the mobilization of the cellular retrotransposon long interspersed nuclear element 1 (LINE-1) independent of cGAS and interferon induction. LINE-1 is the only active autonomous retrotransposable element in the human genome and its transposition can cause genetic and autoimmune diseases. STING inhibition of LINE-1 requires its dimerization. Mechanistically, STING interacts with LINE-1 ORF1p, then the complex translocates to the ER-Golgi intermediate compartment (ERGIC) and the Golgi followed by sorting to Rab7-positive lysosomes for degradation. Our data unveil a function of STING in maintaining host genome integrity by restricting LINE-1 retrotransposition via an IFN-independent mechanism.

Humans↗
PubMed2024

Single-tissue proteomics in Caenorhabditis elegans reveals proteins resident in intestinal lysosome-related organelles.

The nematode intestine is the primary site for nutrient uptake and storage as well as the synthesis of biomolecules; lysosome-related organelles known as gut granules are important for many of these functions. Aspects of intestine biology are not well understood, including the export of the nutrients it imports and the molecules it synthesizes, as well as the complete functions and protein content of the gut granules. Here, we report a mass spectrometry (MS)-based proteomic analysis of the intestine of the Caenorhabditis elegans and of its gut granules. Overall, we identified approximately 5,000 proteins each in the intestine and the gonad and showed that most of these proteins can be detected in samples extracted from a single worm, suggesting the feasibility of individual-level genetic analysis using proteomes. Comparing proteomes and published transcriptomes of the intestine and the gonad, we identified proteins that appear to be synthesized in the intestine and then transferred to the gonad. To identify gut granule proteins, we compared the proteome of individual intestines deficient in gut granules to the wild type. The identified gut granule proteome includes proteins known to be exclusively localized to the granules and additional putative gut granule proteins. We selected two of these putative gut granule proteins for validation via immunohistochemistry, and our successful confirmation of both suggests that our strategy was effective in identifying the gut granule proteome. Our results demonstrate the practicability of single-tissue MS-based proteomic analysis in small organisms and in its future utility.

Animals↗
PubMed2023

SARS-CoV-2 ORF3a expression in brain disrupts the autophagy-lysosomal pathway, impairs sphingolipid homeostasis, and drives neuropathogenesis.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes injury to multiple organ systems, including the brain. SARS-CoV-2's neuropathological mechanisms may include systemic inflammation and hypoxia, as well as direct cell damage resulting from viral infections of neurons and glia. How the virus directly causes injury to brain cells, acutely and over the long term, is not well understood. In order to gain insight into this process, we studied the neuropathological effects of open reading frame 3a (ORF3a), a SARS-CoV-2 accessory protein that is a key pathological factor of the virus. Forced ORF3a brain expression in mice caused the rapid onset of neurological impairment, neurodegeneration, and neuroinflammation-key neuropathological features found in coronavirus disease (COVID-19, which is caused by SARS-CoV-2 infection). Furthermore, ORF3a expression blocked autophagy progression in the brain and caused the neuronal accumulation of α-synuclein and glycosphingolipids, all of which are linked to neurodegenerative disease. Studies with ORF3-expressing HeLa cells confirmed that ORF3a disrupted the autophagy-lysosomal pathway and blocked glycosphingolipid degradation, resulting in their accumulation. These findings indicate that, in the event of neuroinvasion by SARS-CoV-2, ORF3a expression in brain cells may drive neuropathogenesis and be an important mediator of both short- and long-term neurological manifestations of COVID-19.

Animals↗
PubMed2026

Hepatitis C Virus Enhances Lysosome-Associated Membrane Protein 2 A Transcription Through Nuclear Factor Erythroid 2-Related Factor 2 to Support Viral Replication.

Hepatitis C virus (HCV) establishes persistent infection by rewiring host stress-response pathways. Chaperone-mediated autophagy (CMA) contributes to HCV replication, but it remains unclear whether HCV regulates lysosome-associated membrane protein 2 A (LAMP-2A), the rate-limiting receptor for CMA. Here, we examined LAMP-2A regulation in HCV-infected Huh-7.5 cells. HCV infection increased LAMP-2A promoter activity, mRNA, and protein abundance, indicating transcriptional upregulation. Among candidate stress-responsive transcription factors, nuclear factor erythroid 2-related factor 2 (NRF2), hypoxia-inducible factor 1α (HIF-1α), and nuclear factor of activated T cells 1 (NFAT1) were elevated in infected cells. However, promoter mutagenesis identified NRF2 as the principal direct regulator. Mutation of the NRF2-responsive antioxidant response element markedly reduced basal and HCV-induced LAMP-2A promoter activity. Chromatin immunoprecipitation assays revealed NRF2 association with the LAMP-2A promoter, and HCV infection increased nuclear accumulation and Ser40 phosphorylation of NRF2. Functionally, shRNA-mediated knockdown of LAMP-2A reduced intracellular HCV RNA and protein levels. These findings identify an NRF2-LAMP-2A regulatory axis engaged during HCV infection and support a model in which HCV upregulates LAMP-2A to establish a cellular environment favorable for viral replication.

Hepacivirus↗
PubMed2026

Rab10 coordinates SADS-CoV non-lytic egress through the ERGIC-TGN-lysosome trafficking pathway.

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a bat-originated alphacoronavirus that causes devastating enteric disease in neonatal piglets and possesses significant potential for cross-species transmission. While the early stages of the coronavirus life cycle have been extensively characterized, the host factors indispensable for virion assembly and subsequent export remain largely enigmatic. Here, by performing a genome-wide CRISPR-Cas9 knockout screen using a recombinant icSADS-CoV-GFP reporter virus, we identified the small GTPase Rab10 as a critical host dependency factor for SADS-CoV infection. Viral life cycle analysis revealed that Rab10 is not required for viral attachment, entry, or initial genome replication, but is essential for the virion transport and non-lytic egress. Rab10 deficiency markedly reduced the extracellular release of viral RNA, viral proteins, and infectious progeny, as well as the secretion of SADS-CoV virus-like particles. Confocal imaging showed that Rab10 and viral protein-positive intracellular structures were associated with LMAN1, TGN46, and LAMP1 positive compartments. These findings support a model in which Rab10 coordinates a virus-containing vesicles trafficking pathway associated with ERGIC-TGN-lysosome compartments. Mechanistically, Rab10 facilitates the loading of the viral envelope (E) protein into transport vesicles derived from the ERGIC. Rab10 associates with the SADS-CoV E protein, and mapping analyses implicated the C-terminal PDZ-binding motif, particularly residue V75, in efficient Rab10 association and viral release. Collectively, our findings identify Rab10 as a host regulator of SADS-CoV non-lytic egress and highlight the E-Rab10 interaction and the vesicular trafficking machinery as a potential target for developing antiviral strategies.

Animals↗
PubMed2025

COG6 is an essential host factor for influenza A virus infection.

Influenza A virus (IAV) relies on the host cellular machinery to support its replication. Understanding these host dependencies can inform the development of novel antiviral strategies. In this study, we identified conserved oligomeric Golgi complex subunit 6 (COG6) as a novel host factor critical for IAV replication through a genome-wide clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) knockout screen. Disruption of COG6 significantly impaired viral replication. Mechanistically, COG6 supports IAV replication via two distinct means. First, consistent with the role of the COG complex in Golgi homeostasis, COG6 is required for the proper presentation of surface sialic acids, the primary receptor for IAV entry. Second, COG6 deficiency unexpectedly led to lysosome-dependent degradation of viral proteins. Notably, lysosomal activity was also upregulated in IAV-infected wild-type cells, albeit to a lesser extent than in COG6-deficient cells. Treatment with lysosomal inhibitors rescued viral protein stability in COG6 knockout cells. Protein interaction analysis further demonstrated that COG6-mediated stabilization of viral proteins did not rely on viral protein-COG6 interaction, refuting the hypothesis that COG6 acts as a shield factor to protect viral protein from lysosomal degradation. Moreover, knockout of other COG subunits produced similar antiviral effects, suggesting that an intact COG complex is required for IAV replication. Together, these findings uncover a critical role of the COG complex in regulating IAV replication and highlight a previously unappreciated functional link between the Golgi and lysosomes that could be exploited for treating IAV infections.IMPORTANCEDespite advances in virology, numerous host determinants facilitating influenza A virus (IAV) pathogenesis remain uncharacterized. Our study establishes conserved oligomeric Golgi complex subunit 6 (COG6) as a critical host factor promoting IAV infection through complementary mechanisms: receptor modulation and viral protein stabilization. This represents the first demonstration that the COG complex regulates viral pathogenesis through proteostasis mechanisms, fundamentally expanding our understanding of host-virus interactions at the organelle interface. These findings not only provide new perspectives on viral exploitation of Golgi trafficking networks but also identify potential therapeutic targets against evolving influenza strains.

Influenza A virus↗