Reducing Cofilin dosage makes embryos resilient to heat stress.

In addition to regulating the actin cytoskeleton, Cofilin also senses and responds to environmental stress. Cofilin can promote cell survival or death depending on context. Yet, many aspects of Cofilin's role in survival need clarification.

Nuclear Control of Mitochondrial Homeostasis and Venetoclax Efficacy in AML via COX4I1.

Cell signaling pathways are enriched for biological processes crucial for cellular communication, response to external stimuli, and metabolism. Here, a cell signaling-focused CRISPR screen identified cytochrome c oxidase subunit 4 isoform 1 (COX4I1) as a novel vulnerability in acute myeloid leukemia (AML). Depletion of COX4I1 hindered leukemia cell proliferation and impacted in vivo AML progression.

Proteomics analysis reveals the differential impact of the p97 inhibitor CB-5083 on protein levels in various cellular compartments of the HL-60 cell line.

Human p97/VCP is a vital AAA ATPase (ATPase associated with diverse cellular activity) that plays critical roles in protein homeostasis by regulating autophagy, endosomal trafficking, and the ubiquitin-proteasome system. Global proteomics analysis of p97/VCP inhibition with CB-5083 has been performed in HCT116 colon cells. Here, we examined the impact of CB-5083 treatment in another cancer model, the HL-60 acute myeloid leukemia cell line, employing subcellular fractionation combined with label-free proteomics to analyze changes in protein levels across cytoplasmic, nuclear, and insoluble membrane protein compartments.

Cryptic phosphoribosylase activity of NAMPT restricts the virion incorporation of viral proteins.

As obligate intracellular pathogens, viruses activate host metabolic enzymes to supply intermediates that support progeny production. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of salvage nicotinamide adenine dinucleotide (NAD) synthesis, is an interferon-inducible protein that inhibits the replication of several RNA and DNA viruses through unknown mechanisms. Here, we show that NAMPT restricts herpes simplex virus type 1 (HSV-1) replication by impeding the virion incorporation of viral proteins owing to its phosphoribosyl-hydrolase (phosphoribosylase) activity, which is independent of the role of NAMPT in NAD synthesis.

Role of a holo-insertase complex in the biogenesis of biophysically diverse ER membrane proteins.

Mammalian membrane proteins perform essential physiologic functions that rely on their accurate insertion and folding at the endoplasmic reticulum (ER). Using forward and arrayed genetic screens, we systematically studied the biogenesis of a panel of membrane proteins, including several G-protein-coupled receptors (GPCRs). We observed a central role for the insertase, the ER membrane protein complex (EMC), and developed a dual-guide approach to identify genetic modifiers of the EMC.

Mechanism of allosteric inhibition of human p97/VCP ATPase and its disease mutant by triazole inhibitors.

Human p97 ATPase is crucial in various cellular processes, making it a target for inhibitors to treat cancers, neurological, and infectious diseases. Triazole allosteric p97 inhibitors have been demonstrated to match the efficacy of CB-5083, an ATP-competitive inhibitor, in cellular models. However, the mechanism is not well understood.

N-Myristoytransferase Inhibition Causes Mitochondrial Iron Overload and Parthanatos in TIM17A-Dependent Aggressive Lung Carcinoma.

Unlabelled: Myristoylation is a type of protein acylation by which the fatty acid myristate is added to the N-terminus of target proteins, a process mediated by N-myristoyltransferases (NMT). Myristoylation is emerging as a promising cancer therapeutic target; however, the molecular determinants of sensitivity to NMT inhibition or the mechanism by which it induces cancer cell death are not completely understood. We report that NMTs are a novel therapeutic target in lung carcinoma cells with LKB1 and/or KEAP1 mutations in a KRAS-mutant background.

Single-tissue proteomics in 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 and of its gut granules.

Increasing Proteome Coverage Through a Reduction in Analyte Complexity in Single-Cell Equivalent Samples.

The advancement of sophisticated instrumentation in mass spectrometry has catalyzed an in-depth exploration of complex proteomes. This exploration necessitates a nuanced balance in experimental design, particularly between quantitative precision and the enumeration of analytes detected. In bottom-up proteomics, a key challenge is that oversampling of abundant proteins can adversely affect the identification of a diverse array of unique proteins.

Exploring in vivo combinatorial chemo-immunotherapy: Addressing p97 suppression and immune reinvigoration in pancreatic cancer with tumor microenvironment-responsive nanoformulation.

Pancreatic ductal adenocarcinoma (PDAC) has an extremely devastating nature with poor prognosis and increasing incidence, making it a formidable challenge in the global fight against cancer-related mortality. In this innovative preclinical investigation, the VCP/p97 inhibitor CB-5083 (CB), miR-142, a PD-L1 inhibitor, and immunoadjuvant resiquimod (R848; R) were synergistically encapsulated in solid lipid nanoparticles (SLNs). These SLNs demonstrated features of peptides targeting PD-L1, EGFR, and the endoplasmic reticulum, enclosed in a pH-responsive polyglutamic (PGA)-polyethylene glycol (PEG) shell.

Allelic heterogeneity and abnormal vesicle recycling in -related neurodevelopmental disorders.

The human gene encodes Phospholipase-A2-Activating-Protein (PLAA) involved in trafficking of membrane proteins. Through its PUL domain (PLAP, Ufd3p, and Lub1p), PLAA interacts with p97/VCP modulating synaptic vesicles recycling. Although few families carrying biallelic variants were reported with progressive neurodegeneration, consequences of monoallelic variants have not been elucidated.

The Fanconi anemia pathway repairs colibactin-induced DNA interstrand cross-links.

Colibactin is a secondary metabolite produced by bacteria present in the human gut and is implicated in the progression of colorectal cancer and inflammatory bowel disease. This genotoxin alkylates deoxyadenosines on opposite strands of host cell DNA to produce DNA interstrand cross-links (ICLs) that block DNA replication. While cells have evolved multiple mechanisms to resolve ("unhook") ICLs encountered by the replication machinery, little is known about which of these pathways promote resistance to colibactin-induced ICLs.

Role of a holo-insertase complex in the biogenesis of biophysically diverse ER membrane proteins.

Mammalian membrane proteins perform essential physiologic functions that rely on their accurate insertion and folding at the endoplasmic reticulum (ER). Using forward and arrayed genetic screens, we systematically studied the biogenesis of a panel of membrane proteins, including several G-protein coupled receptors (GPCRs). We observed a central role for the insertase, the ER membrane protein complex (EMC), and developed a dual-guide approach to identify genetic modifiers of the EMC.

Impact of Germline Depletion of Bonus on Chromatin State in Ovaries.

Gene expression is controlled via complex regulatory mechanisms involving transcription factors, chromatin modifications, and chromatin regulatory factors. Histone modifications, such as H3K27me3, H3K9ac, and H3K27ac, play an important role in controlling chromatin accessibility and transcriptional output. In vertebrates, the Transcriptional Intermediary Factor 1 (TIF1) family of proteins play essential roles in transcription, cell differentiation, DNA repair, and mitosis.

An innovative nanoformulation utilizing tumor microenvironment-responsive PEG-polyglutamic coating and dynamic charge adjustment for specific targeting of ER stress inducer, microRNA, and immunoadjuvant in pancreatic cancer: In vitro investigations.

Pancreatic ductal adenocarcinoma (PDAC) is a significant obstacle to lowering global cancer deaths. CB-5083, a novel valosin-containing protein (VCP)/p97 inhibitor that disrupts proteasomal degradation and induces endoplasmic reticulum stress (ERS) accumulation, was evaluated as an inducer of immunogenic cell death (ICD) in PDAC treatment. Furthermore, miR-142 enhances checkpoint blockade and promotes M1 repolarization, while Toll-like receptor 7/8 agonist resiquimod (R) acts as an immunoadjuvant to amplify the immune response to miR-142.

The Interferon-inducible NAMPT acts as a protein phosphoribosylase to restrict viral infection.

As obligate intracellular pathogens, viruses often activate host metabolic enzymes to supply intermediates that support progeny production. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of the salvage NAD synthesis, is an interferon-inducible protein that inhibits the replication of several RNA and DNA viruses with unknown mechanism. Here we report that NAMPT restricts herpes simplex virus 1 (HSV-1) replication via phosphoribosyl-hydrolase activity toward key viral structural proteins, independent of NAD synthesis.

An autosomal-dominant childhood-onset disorder associated with pathogenic variants in VCP.

Valosin-containing protein (VCP) is an AAA+ ATPase that plays critical roles in multiple ubiquitin-dependent cellular processes. Dominant pathogenic variants in VCP are associated with adult-onset multisystem proteinopathy (MSP), which manifests as myopathy, bone disease, dementia, and/or motor neuron disease. Through GeneMatcher, we identified 13 unrelated individuals who harbor heterozygous VCP variants (12 de novo and 1 inherited) associated with a childhood-onset disorder characterized by developmental delay, intellectual disability, hypotonia, and macrocephaly.

Acquired resistance to KRAS G12C small-molecule inhibitors via genetic/nongenetic mechanisms in lung cancer.

Inherent or acquired resistance to sotorasib poses a substantialt challenge for NSCLC treatment. Here, we demonstrate that acquired resistance to sotorasib in isogenic cells correlated with increased expression of integrin β4 (ITGB4), a component of the focal adhesion complex. Silencing ITGB4 in tolerant cells improved sotorasib sensitivity, while overexpressing ITGB4 enhanced tolerance to sotorasib by supporting AKT-mTOR bypass signaling.

Skeletal muscle cell protein dysregulation highlights the pathogenesis mechanism of myopathy-associated p97/VCP R155H mutations.

p97/VCP, a hexametric member of the AAA-ATPase superfamily, has been associated with a wide range of cellular protein pathways, such as proteasomal degradation, the unfolding of polyubiquitinated proteins, and autophagosome maturation. Autosomal dominant p97/VCP mutations cause a rare hereditary multisystem disorder called IBMPFD/ALS (Inclusion Body Myopathy with Paget's Disease and Frontotemporal Dementia/Amyotrophic Lateral Sclerosis), characterized by progressive weakness and subsequent atrophy of skeletal muscles, and impacting bones and brains, such as Parkinson's disease, Lewy body disease, Huntington's disease, and amyotrophic lateral ALS. Among all disease-causing mutations, Arginine 155 to Histidine (R155H/+) was reported to be the most common one, affecting over 50% of IBMPFD patients, resulting in disabling muscle weakness, which might eventually be life-threatening due to cardiac and respiratory muscle involvement.

Clinical Classification of Variants in the Valosin-Containing Protein Gene Associated With Multisystem Proteinopathy.

Background And Objectives: Pathogenic variants in the valosin-containing protein () gene cause a phenotypically heterogeneous disorder that includes myopathy, motor neuron disease, Paget disease of the bone, frontotemporal dementia, and parkinsonism termed multisystem proteinopathy. This hallmark pleiotropy makes the classification of novel variants challenging. This retrospective study describes and assesses the effect of 19 novel or nonpreviously clinically characterized variants identified in 28 patients (26 unrelated families) in the retrospective VCP International Multicenter Study.

Optimization of 1,2,4-Triazole-Based p97 Inhibitors for the Treatment of Cancer.

The AAA+ ATPase p97 (valosin-containing protein, VCP) is a master regulator of protein homeostasis and therefore represents a novel target for cancer therapy. Starting from a known allosteric inhibitor, NMS-873, we systematically optimized this scaffold, in particular, by applying a benzene-to-acetylene isosteric replacement strategy, specific incorporation of F, and eutomer/distomer identification, which led to compounds that exhibited nanomolar biochemical and cell-based potency. In cellular pharmacodynamic assays, robust effects on biomarkers of p97 inhibition and apoptosis, including increased levels of ubiquitinated proteins, CHOP and cleaved caspase 3, were observed.

An ankyrin repeat chaperone targets toxic oligomers during amyloidogenesis.

Numerous age-linked diseases are rooted in protein misfolding; this has motivated the development of small molecules and therapeutic antibodies that target the aggregation of disease-linked proteins. Here we explore another approach: molecular chaperones with engineerable protein scaffolds such as the ankyrin repeat domain (ARD). We tested the ability of cpSRP43, a small, robust, ATP- and cofactor-independent plant chaperone built from an ARD, to antagonize disease-linked protein aggregation.