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FEBS Letters Jun 2024Membrane protrusions are fundamental to cellular functions like migration, adhesion, and communication and depend upon dynamic reorganization of the cytoskeleton....
Membrane protrusions are fundamental to cellular functions like migration, adhesion, and communication and depend upon dynamic reorganization of the cytoskeleton. GAP-dependent GTP hydrolysis of Arf proteins regulates actin-dependent membrane remodeling. Here, we show that dAsap regulates membrane protrusions in S2R+ cells by a mechanism that critically relies on its ArfGAP domain and relocalization of actin regulators, SCAR, and Ena. While our data reinforce the preference of dAsap for Arf1 GTP hydrolysis in vitro, we demonstrate that induction of membrane protrusions in S2R+ cells depends on Arf6 inactivation. This study furthers our understanding of how dAsap-dependent GTP hydrolysis maintains a balance between active and inactive states of Arf6 to regulate cell shape.
Topics: ADP-Ribosylation Factor 6; Animals; ADP-Ribosylation Factors; GTPase-Activating Proteins; Actins; Mice; Cell Surface Extensions; Humans; Cell Line; Guanosine Triphosphate; Hydrolysis
PubMed: 38862211
DOI: 10.1002/1873-3468.14954 -
Proceedings of the National Academy of... Jun 2024causes life-threatening wound and gastrointestinal infections, mediated primarily by the production of a Multifunctional-Autoprocessing Repeats-In-Toxin (MARTX) toxin....
causes life-threatening wound and gastrointestinal infections, mediated primarily by the production of a Multifunctional-Autoprocessing Repeats-In-Toxin (MARTX) toxin. The most commonly present MARTX effector domain, the Makes Caterpillars Floppy-like (MCF) toxin, is a cysteine protease stimulated by host adenosine diphosphate (ADP) ribosylation factors (ARFs) to autoprocess. Here, we show processed MCF then binds and cleaves host s-related proteins in rain (Rab) guanosine triphosphatases within their C-terminal tails resulting in Rab degradation. We demonstrate MCF binds Rabs at the same interface occupied by ARFs. Moreover, we show MCF preferentially binds to ARF1 prior to autoprocessing and is active to cleave Rabs only subsequent to autoprocessing. We then use structure prediction algorithms to demonstrate that structural composition, rather than sequence, determines Rab target specificity. We further determine a crystal structure of aMCF as a swapped dimer, revealing an alternative conformation we suggest represents the open, activated state of MCF with reorganized active site residues. The cleavage of Rabs results in Rab1B dispersal within cells and loss of Rab1B density in the intestinal tissue of infected mice. Collectively, our work describes an extracellular bacterial mechanism whereby MCF is activated by ARFs and subsequently induces the degradation of another small host guanosine triphosphatase (GTPase), Rabs, to drive organelle damage, cell death, and promote pathogenesis of these rapidly fatal infections.
Topics: Animals; Female; Humans; Mice; ADP-Ribosylation Factors; Bacterial Toxins; HEK293 Cells; Mice, Inbred ICR; Proteolysis; rab GTP-Binding Proteins; Vibrio Infections; Vibrio vulnificus
PubMed: 38861595
DOI: 10.1073/pnas.2316143121 -
Cellular and Molecular Life Sciences :... Jun 2024Post-transcriptional regulation of cytokine/chemokine mRNA turnover is critical for immune processes and contributes to the mammalian cellular response to diverse...
Post-transcriptional regulation of cytokine/chemokine mRNA turnover is critical for immune processes and contributes to the mammalian cellular response to diverse inflammatory stimuli. The ubiquitous RNA-binding protein human antigen R (HuR) is an integral regulator of inflammation-associated mRNA fate. HuR function is regulated by various post-translational modifications that alter its subcellular localization and ability to stabilize target mRNAs. Both poly (ADP-ribose) polymerase 1 (PARP1) and p38 mitogen-activated protein kinases (MAPKs) have been reported to regulate the biological function of HuR, but their specific regulatory and crosstalk mechanisms remain unclear. In this study, we show that PARP1 acts via p38 to synergistically promote cytoplasmic accumulation of HuR and stabilization of inflammation-associated mRNAs in cells under inflammatory conditions. Specifically, p38 binds to auto-poly ADP-ribosylated (PARylated) PARP1 resulting in the covalent PARylation of p38 by PARP1, thereby promoting the retention and activity of p38 in the nucleus. In addition, PARylation of HuR facilitates the phosphorylation of HuR at the serine 197 site mediated by p38, which then increases the translocation of HuR to the cytoplasm, ultimately stabilizing the inflammation-associated mRNA expression at the post-transcriptional level.
Topics: ELAV-Like Protein 1; p38 Mitogen-Activated Protein Kinases; Humans; Poly (ADP-Ribose) Polymerase-1; Cytoplasm; Inflammation; RNA, Messenger; Phosphorylation; Gene Expression Regulation; Animals; Poly ADP Ribosylation; HEK293 Cells; Cell Nucleus; Mice
PubMed: 38852108
DOI: 10.1007/s00018-024-05292-2 -
The EMBO Journal Jun 2024PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly...
PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly understood due to the lack of sensitive detection methods. Here, we utilised an improved antibody to detect mono-ADP-ribosylation. We visualised endogenous interferon (IFN)-induced ADP-ribosylation and show that PARP14 is a major enzyme responsible for this modification. Fittingly, this signalling is reversed by the macrodomain from SARS-CoV-2 (Mac1), providing a possible mechanism by which Mac1 counteracts the activity of antiviral PARPs. Our data also elucidate a major role of PARP9 and its binding partner, the E3 ubiquitin ligase DTX3L, in regulating PARP14 activity through protein-protein interactions and by the hydrolytic activity of PARP9 macrodomain 1. Finally, we also present the first visualisation of ADPr-dependent ubiquitylation in the IFN response. These approaches should further advance our understanding of IFN-induced ADPr and ubiquitin signalling processes and could shed light on how different pathogens avoid such defence pathways.
PubMed: 38834853
DOI: 10.1038/s44318-024-00126-0 -
The EMBO Journal Jun 2024Protein ADP-ribosylation plays important but ill-defined roles in antiviral signalling cascades such as the interferon response. Several viruses of clinical interest,...
Protein ADP-ribosylation plays important but ill-defined roles in antiviral signalling cascades such as the interferon response. Several viruses of clinical interest, including coronaviruses, express hydrolases that reverse ADP-ribosylation catalysed by host enzymes, suggesting an important role for this modification in host-pathogen interactions. However, which ADP-ribosyltransferases mediate host ADP-ribosylation, what proteins and pathways they target and how these modifications affect viral infection and pathogenesis is currently unclear. Here we show that host ADP-ribosyltransferase activity induced by IFNγ signalling depends on PARP14 catalytic activity and that the PARP9/DTX3L complex is required to uphold PARP14 protein levels via post-translational mechanisms. Both the PARP9/DTX3L complex and PARP14 localise to IFNγ-induced cytoplasmic inclusions containing ADP-ribosylated proteins, and both PARP14 itself and DTX3L are likely targets of PARP14 ADP-ribosylation. We provide evidence that these modifications are hydrolysed by the SARS-CoV-2 Nsp3 macrodomain, shedding light on the intricate cross-regulation between IFN-induced ADP-ribosyltransferases and the potential roles of the coronavirus macrodomain in counteracting their activity.
PubMed: 38834852
DOI: 10.1038/s44318-024-00125-1 -
Pharmacogenomics and Personalized... 2024The IQ motif and Sec7 domain ArfGEF 2 (), an X-linked gene that encodes the BRAG1 protein, is a guanine nucleotide exchange factor for the ADP ribosylation factor (ARF)...
BACKGROUND
The IQ motif and Sec7 domain ArfGEF 2 (), an X-linked gene that encodes the BRAG1 protein, is a guanine nucleotide exchange factor for the ADP ribosylation factor (ARF) protein family in the small guanosine triphosphate (GTP) binding protein. Mutations in this gene result in disorders such as intellectual disability (ID) and epilepsy. In this study, we analyze the clinical features of two patients with -mutation-related disease and discuss their possible pathogenesis.
METHODS
The two patients were diagnosed with ID and epilepsy. Genetic testing was performed using whole-exome sequencing, and the three-dimensional protein structure was analyzed. UCSC Genome Browser was used to analyze the conservation of in different species. We compared expression in the proband families with that in a control group, as well as the expression of the postsynaptic identity protein 95 (PSD-95), synapse-associated protein 97 (SAP97), ADP ribosylation factor 6 (ARF-6), and insulin receptor substrate 53kDa () genes interacting with .
RESULTS
We identified two semi-zygote mutations located in conserved positions in different species: an unreported mutation, C.3576C>A (p. Tyr1192*), and a known mutation, c.2983C>T (p. Arg995Trp). mutations resulted in significant changes in the predicted three-dimensional protein structure, while its expression in the two probands was significantly lower than that in the age-matched control group, and expression in proband 1 was lower than that in his family members. The expression levels of , and , which interact with , were also significantly different from those in the family members and age-matched healthy children.
CONCLUSION
The clinical phenotype resulting from mutations can be explained by the significant decrease in its expression, loss of function of the mutant protein, and change in the expression of related genes. Our results provide novel insights into the molecular phenotype conferred by the variants.
PubMed: 38827181
DOI: 10.2147/PGPM.S455840 -
Molecular Biology Reports Jun 2024Groundnut is vulnerable to the major foliar fungal disease viz., late leaf spot (LLS) and rust in kharif season, which results in severe yield losses. Until now, LLS and...
BACKGROUND
Groundnut is vulnerable to the major foliar fungal disease viz., late leaf spot (LLS) and rust in kharif season, which results in severe yield losses. Until now, LLS and rust resistance linked markers were developed based on GPBD 4 as a major donor source and were validated in its derivatives only, which restricted their use in marker assisted selection (MAS) involving other donors.
METHODS AND RESULTS
The current study focused to validate LLS and rust resistance linked markers employing advanced breeding lines of F generation, derived from nine different crosses involving nine diverse parents, to identify potential markers for marker-assisted breeding of LLS and rust resistance in groundnut. Out of 28-trait linked markers used for validation, 8 were polymorphic (28.57%). Marker-trait association (MTA) and Single Marker Analysis (SMA) revealed that the SSR marker pPGPseq5D05 is significantly associated with both LLS (15.8% PVE) and rust (17.5% PVE) resistance, whereas, the marker IPAHM103 is tightly linked with rust resistance (26.8% PVE) alone. In silico analysis revealed that the marker gene for IPAHM103 is a zinc finger protein and the marker gene for pPGPseq5D05 is an ADP-ribosylation factor GTPase-activating protein. Both these protein products impart resistance or tolerance to biotic stress in crop plants. Two other markers namely, GMLQ975 and pPGPseq13A10 were also found to be associated with LLS resistance explaining MTA up to 60%.
CONCLUSION
These gene specific markers will enable us to screen more number of germplasm lines or newly developed lines in MAS schemes for LLS and rust resistance using a wide range of resistant sources.
Topics: Disease Resistance; Arachis; Plant Diseases; Genetic Markers; Plant Breeding; Basidiomycota; Plant Leaves; Quantitative Trait Loci; Genes, Plant; Chromosome Mapping
PubMed: 38824228
DOI: 10.1007/s11033-024-09633-z -
DNA Repair May 2024DNA strand breaks activate Poly(ADP-ribose) polymerase (PARP) 1 and 2, which use NAD+ as the substrate to covalently conjugate ADP-ribose on themselves and other... (Review)
Review
DNA strand breaks activate Poly(ADP-ribose) polymerase (PARP) 1 and 2, which use NAD+ as the substrate to covalently conjugate ADP-ribose on themselves and other proteins (e.g., Histone) to promote chromatin relaxation and recruit additional DNA repair factors. Enzymatic inhibitors of PARP1 and PARP2 (PARPi) are promising cancer therapy agents that selectively target BRCA1- or BRCA2- deficient cancers. As immediate early responders to DNA strand breaks with robust activities, PARP1 and PARP2 normally form transient foci (<10 minutes) at the micro-irradiation-induced DNA lesions. In addition to enzymatic inhibition, PARPi also extend the presence of PARP1 and PARP2 at DNA lesions, including at replication forks, where they may post a physical block for subsequent repair and DNA replication. The dynamic nature of PARP1 and PARP2 foci made live cell imaging a unique platform to detect subtle changes and the functional interaction among PARP1, PARP2, and their regulators. Recent imaging studies have provided new understandings of the biological consequence of PARP inhibition and uncovered functional interactions between PARP1 and PARP2 and new regulators (e.g., histone poly(ADP-ribosylation) factor). Here, we review recent advances in dissecting the temporal and spatial Regulation of PARP1 and PARP2 at DNA lesions and discuss their physiological implications on both cancer and normal cells.
PubMed: 38823186
DOI: 10.1016/j.dnarep.2024.103690 -
Advanced Science (Weinheim,... May 2024Cholesterol 25-hydroxylase (CH25H), an enzyme involved in cholesterol metabolism, regulates inflammatory responses and lipid metabolism. However, its role in kidney...
Cholesterol 25-hydroxylase (CH25H), an enzyme involved in cholesterol metabolism, regulates inflammatory responses and lipid metabolism. However, its role in kidney disease is not known. The author found that CH25H transcript is expressed mostly in glomerular and peritubular endothelial cells and that its expression increased in human and mouse diabetic kidneys. Global deletion of Ch25h in Lepr mice aggravated diabetic kidney disease (DKD), which is associated with increased endothelial cell apoptosis. Treatment of 25-hydroxycholesterol (25-HC), the product of CH25H, alleviated kidney injury in Lepr mice. Mechanistically, 25-HC binds to GTP-binding protein ADP-ribosylation factor 4 (ARF4), an essential protein required for maintaining protein transport in the Golgi apparatus. Interestingly, ARF4's GTPase-activating protein ASAP1 is also predominantly expressed in endothelial cells and its expression increased in DKD. Suppression of ARF4 activity by deleting ARF4 or overexpressing ASAP1 results in endothelial cell death. These results indicate that 25-HC binds ARF4 to inhibit its interaction with ASAP1, and thereby resulting in enhanced ARF4 activity to confer renoprotection. Therefore, treatment of 25-HC improves kidney injury in DKD in part by restoring ARF4 activity to maintain endothelial cell survival. This study provides a novel mechanism and a potential new therapy for DKD.
PubMed: 38816950
DOI: 10.1002/advs.202309642 -
Ageing Research Reviews Jul 2024Aging, a complex biological process, plays key roles the development of multiple disorders referred as aging-related diseases involving cardiovascular diseases, stroke,... (Review)
Review
Aging, a complex biological process, plays key roles the development of multiple disorders referred as aging-related diseases involving cardiovascular diseases, stroke, neurodegenerative diseases, cancers, lipid metabolism-related diseases. ADP-ribosylation is a reversible modification onto proteins and nucleic acids to alter their structures and/or functions. Growing evidence support the importance of ADP-ribosylation and ADP-ribosylation-associated enzymes in aging and age-related diseases. In this review, we summarized ADP-ribosylation-associated proteins including ADP-ribosyl transferases, the ADP-ribosyl hydrolyses and ADP-ribose binding domains. Furthermore, we outlined the latest knowledge about regulation of ADP-ribosylation in the pathogenesis and progression of main aging-related diseases, organism aging and cellular senescence, and we also speculated the underlying mechanisms to better disclose this novel molecular network. Moreover, we discussed current issues and provided an outlook for future research, aiming to revealing the unknown bio-properties of ADP-ribosylation, and establishing a novel therapeutic perspective in aging-related diseases and health aging via targeting ADP-ribosylation.
Topics: Humans; Aging; ADP-Ribosylation; Animals; Cellular Senescence; Neurodegenerative Diseases
PubMed: 38815933
DOI: 10.1016/j.arr.2024.102347