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1.
Development ; 148(17)2021 09 01.
Article in English | MEDLINE | ID: mdl-34414407

ABSTRACT

Reelin is a large secreted glycoprotein that regulates neuronal migration, lamination and establishment of dendritic architecture in the embryonic brain. Reelin expression switches postnatally from Cajal-Retzius cells to interneurons. However, reelin function in interneuron development is still poorly understood. Here, we have investigated the role of reelin in interneuron development in the postnatal neocortex. To preclude early cortical migration defects caused by reelin deficiency, we employed a conditional reelin knockout (RelncKO) mouse to induce postnatal reelin deficiency. Induced reelin deficiency caused dendritic hypertrophy in distal dendritic segments of neuropeptide Y-positive (NPY+) and calretinin-positive (Calr+) interneurons, and in proximal dendritic segments of parvalbumin-positive (Parv+) interneurons. Chronic recombinant Reelin treatment rescued dendritic hypertrophy in Relncko interneurons. Moreover, we provide evidence that RelncKO interneuron hypertrophy is due to presynaptic GABABR dysfunction. Thus, GABABRs in RelncKO interneurons were unable to block N-type (Cav2.2) Ca2+ channels that control neurotransmitter release. Consequently, the excessive Ca2+ influx through AMPA receptors, but not NMDA receptors, caused interneuron dendritic hypertrophy. These findings suggest that reelin acts as a 'stop-growth-signal' for postnatal interneuron maturation.


Subject(s)
Cell Adhesion Molecules, Neuronal/metabolism , Dendrites/metabolism , Extracellular Matrix Proteins/metabolism , Interneurons/cytology , Neocortex/growth & development , Nerve Tissue Proteins/metabolism , Serine Endopeptidases/metabolism , Animals , Calbindin 2/metabolism , Calcium/metabolism , Cell Adhesion Molecules, Neuronal/deficiency , Cell Adhesion Molecules, Neuronal/pharmacology , Dendrites/drug effects , Extracellular Matrix Proteins/deficiency , Extracellular Matrix Proteins/pharmacology , Hypertrophy , Interneurons/drug effects , Interneurons/metabolism , Mice , Mice, Knockout , Neocortex/cytology , Neocortex/drug effects , Neocortex/pathology , Nerve Tissue Proteins/deficiency , Nerve Tissue Proteins/pharmacology , Neuropeptide Y/metabolism , Parvalbumins/metabolism , Receptors, GABA-B/metabolism , Receptors, Glutamate/metabolism , Reelin Protein , Serine Endopeptidases/deficiency , Serine Endopeptidases/pharmacology
2.
Neurosci Lett ; 763: 136181, 2021 10 15.
Article in English | MEDLINE | ID: mdl-34416345

ABSTRACT

Motopsin is a serine protease that plays a crucial role in synaptic functions. Loss of motopsin function causes severe intellectual disability in humans. In this study, we evaluated the role of motopsin in the neuropathological development of cognitive impairments following chemotherapy, also known as chemobrain. Motopsin knockout (KO) and wild-type (WT) mice were intravenously injected with doxorubicin (Dox) or saline four times every 8 days and were evaluated for open field, novel object recognition, and passive avoidance tests. Parvalbumin-positive neurons in the hippocampus were immunohistochemically analyzed. Dox administration significantly decreased the total distance in the open field test in both WT and motopsin KO mice without affecting the duration spent in the center square. A significant interaction between the genotype and drug treatment was detected in the recognition index (the rate to investigate a novel object) in the novel object recognition test, although Dox treatment did not affect the total investigation time. Additionally, Dox treatment significantly decreased the recognition index in WT mice, whereas it tended to increase the recognition index in motopsin KO mice. Dox treatment did not affect the latency to enter a dark compartment in either WT or motopsin KO mice in the passive avoidance test. Interestingly, Dox treatment increased the parvalbumin-positive neurons in the stratum oriens of the hippocampus CA1 region of only WT mice, not motopsin KO mice. Our data suggest that motopsin deficiency imparted partial insensitivity to Dox-induced hippocampal impairments. Alternatively, motopsin may contribute to the neuropathology of chemobrain.


Subject(s)
CA1 Region, Hippocampal/pathology , CA3 Region, Hippocampal/pathology , Chemotherapy-Related Cognitive Impairment/pathology , Doxorubicin/adverse effects , Serine Endopeptidases/deficiency , Animals , CA1 Region, Hippocampal/cytology , CA1 Region, Hippocampal/drug effects , CA3 Region, Hippocampal/drug effects , Chemotherapy-Related Cognitive Impairment/etiology , Disease Models, Animal , Humans , Locomotion/drug effects , Male , Mice , Mice, Knockout , Neuronal Ceroid-Lipofuscinoses/genetics , Neuronal Ceroid-Lipofuscinoses/pathology , Neurons/drug effects , Neurons/pathology , Parvalbumins/metabolism , Serine Endopeptidases/genetics
3.
Int J Mol Sci ; 22(5)2021 Mar 06.
Article in English | MEDLINE | ID: mdl-33800732

ABSTRACT

Matriptase-2, a serine protease expressed in hepatocytes, is a negative regulator of hepcidin expression. The purpose of the study was to investigate the interaction of matriptase-2 with hemojuvelin protein in vivo. Mice lacking the matriptase-2 proteolytic activity (mask mice) display decreased content of hemojuvelin protein. Vice versa, the absence of hemojuvelin results in decreased liver content of matriptase-2, indicating that the two proteins interact. To further characterize the role of matriptase-2, we investigated iron metabolism in mask mice fed experimental diets. Administration of iron-enriched diet increased liver iron stores as well as hepcidin expression. Treatment of iron-overloaded mask mice with erythropoietin increased hemoglobin and hematocrit, indicating that the response to erythropoietin is intact in mask mice. Feeding of an iron-deficient diet to mask mice significantly increased spleen weight as well as the splenic content of erythroferrone and transferrin receptor proteins, indicating stress erythropoiesis. Liver hepcidin expression was decreased; expression of Id1 was not changed. Overall, the results suggest a complex interaction between matriptase-2 and hemojuvelin, and demonstrate that hepcidin can to some extent be regulated even in the absence of matriptase-2 proteolytic activity.


Subject(s)
GPI-Linked Proteins/physiology , Hemochromatosis Protein/physiology , Iron Overload/metabolism , Membrane Proteins/physiology , Serine Endopeptidases/physiology , Animals , Bone Morphogenetic Protein 6/biosynthesis , Bone Morphogenetic Protein 6/genetics , Erythropoietin/pharmacology , Female , GPI-Linked Proteins/biosynthesis , GPI-Linked Proteins/deficiency , GPI-Linked Proteins/genetics , Gene Expression Regulation/drug effects , Hemochromatosis Protein/biosynthesis , Hemochromatosis Protein/deficiency , Hemochromatosis Protein/genetics , Hepcidins/biosynthesis , Hepcidins/genetics , Inhibitor of Differentiation Protein 1/biosynthesis , Inhibitor of Differentiation Protein 1/genetics , Iron Deficiencies , Iron, Dietary/pharmacology , Liver/metabolism , Male , Membrane Proteins/deficiency , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Organ Specificity , Promoter Regions, Genetic/genetics , Protein Domains , Recombinant Proteins/metabolism , Serine Endopeptidases/deficiency , Serine Endopeptidases/genetics , Spleen/metabolism
4.
Mol Cell Neurosci ; 112: 103614, 2021 04.
Article in English | MEDLINE | ID: mdl-33845123

ABSTRACT

Homozygous Dab1 yotari mutant mice, Dab1yot (yot/yot) mice, have an autosomal recessive mutation of Dab1 and show reeler-like phenotype including histological abnormality of the cerebellum, hippocampus, and cerebral cortex. We here show abnormal hippocampal development of yot/yot mice where granule cells and pyramidal cells fail to form orderly rows but are dispersed diffusely in vague multiplicative layers. Possibly due to the positioning failure of granule cells and pyramidal cells and insufficient synaptogenesis, axons of the granule cells did not extend purposefully to connect with neighboring regions in yot/yot mice. We found that both hippocampal granule cells and pyramidal cells of yot/yot mice expressed proteins reactive with the anti-Dab1 antibody. We found that Y198- phosphorylated Dab1 of yot/yot mice was greatly decreased. Accordingly the downstream molecule, Akt was hardly phosphorylated. Especially, synapse formation was defective and the distribution of neurons was scattered in hippocampus of yot/yot mice. Some of neural cell adhesion molecules and hippocampus associated transcription factors of the neurons were expressed aberrantly, suggesting that the Reelin-Dab1 signaling pathway seemed to be importantly involved in not only neural migration as having been shown previously but also neural maturation and/or synaptogenesis of the mice. It is interesting to clarify whether the defective neural maturation is a direct consequence of the dysfunctional Dab1, or alternatively secondarily due to the Reelin-Dab1 intracellular signaling pathways.


Subject(s)
Cell Adhesion Molecules, Neuronal/physiology , Extracellular Matrix Proteins/physiology , Hippocampus/abnormalities , Mice, Mutant Strains/abnormalities , Nerve Tissue Proteins/physiology , Serine Endopeptidases/physiology , Signal Transduction/physiology , Animals , Cell Adhesion Molecules, Neuronal/deficiency , Cell Movement , Enzyme Activation , Extracellular Matrix Proteins/deficiency , Genes, Recessive , Hippocampus/embryology , Hippocampus/metabolism , Hippocampus/pathology , Homozygote , Mice , Mice, Mutant Strains/genetics , Mice, Mutant Strains/metabolism , Nerve Tissue Proteins/biosynthesis , Nerve Tissue Proteins/deficiency , Nerve Tissue Proteins/genetics , Neural Cell Adhesion Molecules/biosynthesis , Neural Cell Adhesion Molecules/genetics , Phenotype , Phosphorylation , Protein Processing, Post-Translational , Proto-Oncogene Proteins c-akt/metabolism , Reelin Protein , Serine Endopeptidases/deficiency , Synapses/metabolism , Transcription Factors/biosynthesis , Transcription Factors/genetics
6.
Arterioscler Thromb Vasc Biol ; 41(4): 1309-1318, 2021 04.
Article in English | MEDLINE | ID: mdl-33626909
7.
PLoS Pathog ; 17(1): e1009233, 2021 01.
Article in English | MEDLINE | ID: mdl-33476327

ABSTRACT

The spike (S) protein of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) binds to a host cell receptor which facilitates viral entry. A polybasic motif detected at the cleavage site of the S protein has been shown to broaden the cell tropism and transmissibility of the virus. Here we examine the properties of SARS-CoV-2 variants with mutations at the S protein cleavage site that undergo inefficient proteolytic cleavage. Virus variants with S gene mutations generated smaller plaques and exhibited a more limited range of cell tropism compared to the wild-type strain. These alterations were shown to result from their inability to utilize the entry pathway involving direct fusion mediated by the host type II transmembrane serine protease, TMPRSS2. Notably, viruses with S gene mutations emerged rapidly and became the dominant SARS-CoV-2 variants in TMPRSS2-deficient cells including Vero cells. Our study demonstrated that the S protein polybasic cleavage motif is a critical factor underlying SARS-CoV-2 entry and cell tropism. As such, researchers should be alert to the possibility of de novo S gene mutations emerging in tissue-culture propagated virus strains.


Subject(s)
SARS-CoV-2/genetics , Serine Endopeptidases/deficiency , Spike Glycoprotein, Coronavirus/genetics , Amino Acid Sequence , Animals , Caco-2 Cells , Cell Line , Chlorocebus aethiops , HEK293 Cells , Humans , Mutation , SARS-CoV-2/classification , SARS-CoV-2/growth & development , SARS-CoV-2/physiology , Sequence Alignment , Serial Passage , Vero Cells , Viral Tropism
8.
Neurochem Int ; 144: 104954, 2021 03.
Article in English | MEDLINE | ID: mdl-33388358

ABSTRACT

Reelin, an extracellular matrix protein, is secreted by Cajal-Retzius cells and plays crucial roles in the development of brain structures and neuronal functions. Reductions in Reelin cause the brain dysfunctions associated with mental disorders, such as schizophrenia. A recent genome-wide copy number variation analysis of Japanese schizophrenia patients identified a novel deletion in RELN encoding Reelin. To clarify the pathophysiological role of the RELN deletion, we developed transgenic mice carrying the RELN deletion (Reln-del) and found abnormalities in their brain structures and social behavior. In the present study, we performed an in vitro analysis of Reelin expression, intracellular Reelin signaling, and the morphology of primary cultured cortical neurons from wild-type (WT) and Reln-del mice. Reelin protein levels were lower in Reln-del neurons than in WT neurons. Dab1 expression levels were significantly higher in Reln-del neurons than in WT neurons, suggesting that Reelin signaling was decreased in Reln-del neurons. Reelin was mainly expressed in γ-aminobutyric acid (GABA)-ergic inhibitory neurons, but not in parvalbumin (PV)-positive neurons. A small proportion of Ca2+/calmodulin-dependent protein kinase II α subunit (CaMKIIα)-positive excitatory neurons also expressed Reelin. In comparisons with WT neurons, significant decreases were observed in neurite lengths and branch points as well as in the number of postsynaptic density protein 95 (PSD95) immunoreactive puncta in Reln-del neurons. A disintegrin and metalloproteinase with thrombospondin motifs-3 (ADAMTS-3) is a protease that inactivates Reelin by cleavage at the N-t site. The knockdown of ADAMTS-3 by short hairpin RNAs suppressed Reelin cleavage in conditioned medium and reduced Dab1 expression, indicating that Reelin signaling was enhanced in the primary cultured cortical neurons of WT and heterozygous Reln-del. Accordingly, the inhibition of ADAMTS-3 may be a potential candidate in the clinical treatment of schizophrenia by enhancing Reelin signaling in the brain.


Subject(s)
Cell Adhesion Molecules, Neuronal/deficiency , Cerebral Cortex/metabolism , Extracellular Matrix Proteins/deficiency , Gene Deletion , Nerve Tissue Proteins/deficiency , Neurons/metabolism , Schizophrenia/metabolism , Serine Endopeptidases/deficiency , Animals , Cell Adhesion Molecules, Neuronal/biosynthesis , Cell Adhesion Molecules, Neuronal/genetics , Cells, Cultured , Cerebral Cortex/cytology , Extracellular Matrix Proteins/biosynthesis , Extracellular Matrix Proteins/genetics , HEK293 Cells , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Nerve Tissue Proteins/biosynthesis , Nerve Tissue Proteins/genetics , Reelin Protein , Schizophrenia/genetics , Serine Endopeptidases/biosynthesis , Serine Endopeptidases/genetics , Signal Transduction/physiology
9.
J Biosci Bioeng ; 131(1): 33-38, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32972822

ABSTRACT

Flocculation is an aggregation phenomenon of microbial cells in which they form flocs or flakes. In this study, it was found that addition of glycerol to a complex glucose medium promoted spontaneous floc formation by an Escherichia coli degP-deficient mutant strain (ΔdegP) in a dose-dependent manner. In the presence of 10% (v/v) glycerol, the amount of floc formation (quantified as floc protein) reached its maximum value (230 mg/L), five times that in its absence. 10% (v/v) glycerol was the limit concentration that does not inhibit cell growth of ΔdegP strain. Glycerol was not consumed by ΔdegP cells during floc formation. To provide media having nearly the same viscosity as that containing 10% (v/v) glycerol, carboxymethyl cellulose (CMC) or polyvinylpyrrolidone (PVP) were added to medium as viscosifying agents. Floc formation was not promoted by increasing the medium viscosity with CMC or PVP. However, addition of ethylene glycol also significantly promoted floc formation in the same manner as glycerol. Addition of short-chain polyols decreased the number of viable ΔdegP cells in the floc structure and enhanced outer membrane vesicle (OMV) production by ΔdegP cells; polyols-induced damage on the outer membrane of ΔdegP cells may contribute to the promoted floc formation.


Subject(s)
Escherichia coli/cytology , Escherichia coli/drug effects , Glycerol/pharmacology , Heat-Shock Proteins/deficiency , Serine Endopeptidases/deficiency , Flocculation/drug effects , Periplasmic Proteins
10.
FEBS J ; 288(2): 600-613, 2021 01.
Article in English | MEDLINE | ID: mdl-32491259

ABSTRACT

The mitochondrial proteome is built and maintained mainly by import of nuclear-encoded precursor proteins. Most of these precursors use N-terminal presequences as targeting signals that are removed by mitochondrial matrix proteases. The essential mitochondrial processing protease MPP cleaves presequences after import into the organelle thereby enabling protein folding and functionality. The cleaved presequences are subsequently degraded by peptidases. While most of these processes have been discovered in yeast, characterization of the human enzymes is still scarce. As the matrix presequence peptidase PreP has been reported to play a role in Alzheimer's disease, analysis of impaired peptide turnover in human cells is of huge interest. Here, we report the characterization of HEK293T PreP knockout cells. Loss of PreP causes severe defects in oxidative phosphorylation and changes in nuclear expression of stress response marker genes. The mitochondrial defects upon lack of PreP result from the accumulation of presequence peptides that trigger feedback inhibition of MPP and accumulation of nonprocessed precursor proteins. Also, the mitochondrial intermediate peptidase MIP that cleaves eight residues from a subset of precursors after MPP processing is compromised upon loss of PreP suggesting that PreP also degrades MIP generated octapeptides. Investigation of the PrePR183Q patient mutation associated with neurological disorders revealed that the mutation destabilizes the protein making it susceptible to enhanced degradation and aggregation upon heat shock. Taken together, our data reveal a functional coupling between precursor processing by MPP and MIP and presequence degradation by PreP in human mitochondria that is crucial to maintain a functional organellar proteome.


Subject(s)
Feedback, Physiological , Metalloendopeptidases/genetics , Mitochondria/genetics , Mitochondrial Proteins/genetics , Serine Endopeptidases/genetics , Amino Acid Sequence , Base Sequence , CRISPR-Cas Systems , Cell Fractionation , Cell Proliferation , Gene Knockout Techniques , HEK293 Cells , Humans , Metalloendopeptidases/metabolism , Mitochondria/metabolism , Mitochondria/pathology , Mitochondrial Proteins/deficiency , Mutation , Oligopeptides/genetics , Oligopeptides/metabolism , Oxidative Phosphorylation , Proteolysis , Serine Endopeptidases/deficiency , Stress, Physiological/genetics , Mitochondrial Processing Peptidase
11.
J Neurochem ; 156(5): 589-603, 2021 03.
Article in English | MEDLINE | ID: mdl-32083308

ABSTRACT

Reelin is a protein that is best known for its role in controlling neuronal layer formation in the developing cortex. Here, we studied its role for post-natal cortical network function, which is poorly explored. To preclude early cortical migration defects caused by Reelin deficiency, we used a conditional Reelin knock-out (RelncKO ) mouse, and induced Reelin deficiency post-natally. Induced Reelin deficiency caused hyperexcitability of the neocortical network in vitro and ex vivo. Blocking Reelin binding to its receptors ApoER2 and VLDLR resulted in a similar effect. Hyperexcitability in RelncKO organotypic slice cultures could be rescued by co-culture with wild-type organotypic slice cultures. Moreover, the GABAB receptor (GABAB R) agonist baclofen failed to activate and the antagonist CGP35348 failed to block GABAB Rs in RelncKO mice. Immunolabeling of RelncKO cortical slices revealed a reduction in GABAB R1 and GABAB R2 surface expression at the plasma membrane and western blot of RelncKO cortical tissue revealed decreased phosphorylation of the GABAB R2 subunit at serine 892 and increased phosphorylation at serine 783, reflecting receptor deactivation and proteolysis. These data show a role of Reelin in controlling early network activity, by modulating GABAB R function. Cover Image for this issue: https://doi.org/10.1111/jnc.15054.


Subject(s)
Cell Adhesion Molecules, Neuronal/deficiency , Extracellular Matrix Proteins/deficiency , Neocortex/metabolism , Nerve Tissue Proteins/deficiency , Receptors, GABA-B/physiology , Serine Endopeptidases/deficiency , Signal Transduction/physiology , Animals , Animals, Newborn , Cell Adhesion Molecules, Neuronal/genetics , Extracellular Matrix Proteins/genetics , Female , GABA-B Receptor Agonists/pharmacology , Male , Mice , Mice, Knockout , Nerve Tissue Proteins/genetics , Organ Culture Techniques , Reelin Protein , Serine Endopeptidases/genetics , Signal Transduction/drug effects
12.
Nature ; 588(7839): 705-711, 2020 12.
Article in English | MEDLINE | ID: mdl-33299187

ABSTRACT

Recent studies have suggested that lymphatics help to restore heart function after cardiac injury1-6. Here we report that lymphatics promote cardiac growth, repair and cardioprotection in mice. We show that a lymphoangiocrine signal produced by lymphatic endothelial cells (LECs) controls the proliferation and survival of cardiomyocytes during heart development, improves neonatal cardiac regeneration and is cardioprotective after myocardial infarction. Embryos that lack LECs develop smaller hearts as a consequence of reduced cardiomyocyte proliferation and increased cardiomyocyte apoptosis. Culturing primary mouse cardiomyocytes in LEC-conditioned medium increases cardiomyocyte proliferation and survival, which indicates that LECs produce lymphoangiocrine signals that control cardiomyocyte homeostasis. Characterization of the LEC secretome identified the extracellular protein reelin (RELN) as a key component of this process. Moreover, we report that LEC-specific Reln-null mouse embryos develop smaller hearts, that RELN is required for efficient heart repair and function after neonatal myocardial infarction, and that cardiac delivery of RELN using collagen patches improves heart function in adult mice after myocardial infarction by a cardioprotective effect. These results highlight a lymphoangiocrine role of LECs during cardiac development and injury response, and identify RELN as an important mediator of this function.


Subject(s)
Heart/embryology , Lymphatic System/cytology , Lymphatic System/metabolism , Myocardium/cytology , Myocytes, Cardiac/cytology , Regeneration , Signal Transduction , Animals , Animals, Newborn , Apoptosis , Cell Adhesion Molecules, Neuronal/deficiency , Cell Adhesion Molecules, Neuronal/genetics , Cell Adhesion Molecules, Neuronal/metabolism , Cell Proliferation , Cell Survival , Cells, Cultured , Endothelial Cells/metabolism , Extracellular Matrix Proteins/deficiency , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Female , Humans , Integrin beta1/metabolism , Mice , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocytes, Cardiac/metabolism , Nerve Tissue Proteins/deficiency , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Organ Size , Organogenesis , Reelin Protein , Serine Endopeptidases/deficiency , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism
13.
Arterioscler Thromb Vasc Biol ; 40(10): 2391-2403, 2020 10.
Article in English | MEDLINE | ID: mdl-32787521

ABSTRACT

OBJECTIVE: Reelin, a secreted glycoprotein, was originally identified in the central nervous system, where it plays an important role in brain development and maintenance. In the cardiovascular system, reelin plays a role in atherosclerosis by enhancing vascular inflammation and in arterial thrombosis by promoting platelet adhesion, activation, and thrombus formation via APP (amyloid precursor protein) and GP (glycoprotein) Ib. However, the role of reelin in hemostasis and arterial thrombosis is not fully understood to date. Approach and Results: In the present study, we analyzed the importance of reelin for cytoskeletal reorganization of platelets and thrombus formation in more detail. Platelets release reelin to amplify alphaIIb beta3 integrin outside-in signaling by promoting platelet adhesion, cytoskeletal reorganization, and clot retraction via activation of Rho GTPases RAC1 (Ras-related C3 botulinum toxin substrate) and RhoA (Ras homolog family member A). Reelin interacts with the collagen receptor GP (glycoprotein) VI with subnanomolar affinity, induces tyrosine phosphorylation in a GPVI-dependent manner, and supports platelet binding to collagen and GPVI-dependent RAC1 activation, PLC gamma 2 (1-phosphatidylinositol-4,5-bisphosphate phosphodiesterase gamma-2) phosphorylation, platelet activation, and aggregation. When GPVI was deleted from the platelet surface by antibody treatment in reelin-deficient mice, thrombus formation was completely abolished after injury of the carotid artery while being only reduced in either GPVI-depleted or reelin-deficient mice. CONCLUSIONS: Our study identified a novel signaling pathway that involves reelin-induced GPVI activation and alphaIIb beta3 integrin outside-in signaling in platelets. Loss of both, GPVI and reelin, completely prevents stable arterial thrombus formation in vivo suggesting that inhibiting reelin-platelet-interaction might represent a novel strategy to avoid arterial thrombosis in cardiovascular disease.


Subject(s)
Blood Platelets/enzymology , Carotid Artery Injuries/enzymology , Cell Adhesion Molecules, Neuronal/blood , Extracellular Matrix Proteins/blood , Nerve Tissue Proteins/blood , Neuropeptides/blood , Phospholipase C gamma/blood , Platelet Glycoprotein GPIIb-IIIa Complex/metabolism , Platelet Membrane Glycoproteins/metabolism , Serine Endopeptidases/blood , Thrombosis/enzymology , rac1 GTP-Binding Protein/blood , rhoA GTP-Binding Protein/blood , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Animals , Blood Coagulation , Carotid Artery Injuries/blood , Carotid Artery Injuries/etiology , Cell Adhesion Molecules, Neuronal/deficiency , Cell Adhesion Molecules, Neuronal/genetics , Clot Retraction , Cytoskeleton/enzymology , Disease Models, Animal , Extracellular Matrix Proteins/deficiency , Extracellular Matrix Proteins/genetics , Mice, 129 Strain , Mice, Inbred C3H , Mice, Inbred C57BL , Nerve Tissue Proteins/deficiency , Nerve Tissue Proteins/genetics , Platelet Activation , Reelin Protein , Serine Endopeptidases/deficiency , Serine Endopeptidases/genetics , Signal Transduction , Thrombosis/blood , Thrombosis/etiology
14.
Sci Rep ; 10(1): 11731, 2020 07 16.
Article in English | MEDLINE | ID: mdl-32678161

ABSTRACT

The digestive enzyme chymotrypsin protects the pancreas against pancreatitis by reducing harmful trypsin activity. Genetic deficiency in chymotrypsin increases pancreatitis risk in humans and pancreatitis severity in mice. Pancreatic chymotrypsin is produced in multiple isoforms including chymotrypsin B1, B2, C and chymotrypsin-like protease (CTRL). Here we investigated the role of CTRL in cerulein-induced pancreatitis in mice. Biochemical experiments with recombinant mouse enzymes demonstrated that CTRL cleaved trypsinogens and suppressed trypsin activation. We generated a novel CTRL-deficient strain (Ctrl-KO) using CRISPR-Cas9 genome engineering. Homozygous Ctrl-KO mice expressed no detectable CTRL protein in the pancreas. Remarkably, the total chymotrypsinogen content in Ctrl-KO mice was barely reduced indicating that CTRL is a low-abundance isoform. When given cerulein, Ctrl-KO mice exhibited lower intrapancreatic chymotrypsin activation and a trend for higher trypsin activation, compared with C57BL/6N mice. Despite the altered protease activation, severity of cerulein-induced acute pancreatitis was similar in Ctrl-KO and C57BL/6N mice. We conclude that CTRL is a minor chymotrypsin isoform that plays no significant role in cerulein-induced pancreatitis in mice.


Subject(s)
Pancreas/enzymology , Pancreatitis/etiology , Pancreatitis/metabolism , Serine Endopeptidases/deficiency , Acute Disease , Animals , Biopsy , Cell Line , Chymotrypsin/metabolism , Disease Models, Animal , Enzyme Activation , Gene Expression , Humans , Immunohistochemistry , Mice , Mice, Knockout , Pancreatitis/pathology , Peroxidase/genetics , Peroxidase/metabolism , Severity of Illness Index , Trypsin/metabolism
15.
PLoS One ; 15(6): e0234407, 2020.
Article in English | MEDLINE | ID: mdl-32511276

ABSTRACT

Testisin (encoded by PRSS21) is a membrane anchored serine protease, which is tethered to the cell surface via a glycosylphosphatidylinositol (GPI)-anchor. While testisin is found in abundance in spermatozoa, it is also expressed in microvascular endothelial cells where its function is unknown. Here we identify testisin as a novel regulator of physiological hormone-induced angiogenesis and microvascular endothelial permeability. Using a murine model of rapid physiological angiogenesis during corpus luteal development in the ovary, we found that mice genetically deficient in testisin (Prss21-/-) show a substantially increased incidence of hemorrhages which are significantly more severe than in littermate control Prss21+/+ mice. This phenotype was associated with increased vascular leakiness, demonstrated by a greater accumulation of extravasated Evans blue dye in Prss21-/- ovaries. Live cell imaging of in vitro cultured microvascular endothelial cells depleted of testisin by siRNA knockdown revealed that loss of testisin markedly impaired reorganization and tubule-like formation on Matrigel basement membranes. Moreover testisin siRNA knockdown increased the paracellular permeability to FITC-albumin across endothelial cell monolayers, which was associated with decreased expression of the adherens junction protein VE-cadherin and increased levels of phospho(Tyr658)-VE-cadherin, without affecting the levels of the tight junction proteins occludin and claudin-5, or ZO-1. Decreased expression of VE-cadherin in the neovasculature of Prss21-/- ovaries was also observed without marked differences in endothelial cell content, vascular claudin-5 expression or pericyte recruitment. Together, these data identify testisin as a novel regulator of VE-cadherin adhesions during angiogenesis and indicate a potential new target for regulating neovascular integrity and associated pathologies.


Subject(s)
Capillary Permeability/physiology , Corpus Luteum/blood supply , Neovascularization, Physiologic , Serine Endopeptidases/deficiency , Animals , Antigens, CD/metabolism , Cadherins/metabolism , Capillary Permeability/genetics , Cells, Cultured , Corpus Luteum/pathology , Corpus Luteum/physiopathology , Female , GPI-Linked Proteins/antagonists & inhibitors , GPI-Linked Proteins/deficiency , GPI-Linked Proteins/genetics , GPI-Linked Proteins/physiology , Gene Knockdown Techniques , Hemorrhage/etiology , Hemorrhage/genetics , Hemorrhage/physiopathology , Humans , Luteinization/genetics , Luteinization/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Neovascularization, Physiologic/genetics , Phenotype , Serine Endopeptidases/genetics , Serine Endopeptidases/physiology
16.
Infect Immun ; 88(8)2020 07 21.
Article in English | MEDLINE | ID: mdl-32513856

ABSTRACT

Staphylococcus aureus fatty acid kinase FakA is necessary for the incorporation of exogenous fatty acids into the lipid membrane. We previously demonstrated that the inactivation of fakA leads to decreased α-hemolysin (Hla) production but increased expression of the proteases SspAB and aureolysin in vitro, and that the ΔfakA mutant causes larger lesions than the wild type (WT) during murine skin infection. As expected, necrosis is Hla dependent in the presence or absence of FakA, as both hla and hla ΔfakA mutants are unable to cause necrosis of the skin. At day 4 postinfection, while the ΔfakA mutant maintains larger and more necrotic abscesses, bacterial numbers are similar to those of the WT, indicating the enhanced tissue damage of mice infected with the ΔfakA mutant is not due to an increase in bacterial burden. At this early stage of infection, skin infected with the ΔfakA mutant has decreased levels of proinflammatory cytokines, such as interleukin-17A (IL-17A) and IL-1α, compared to those of WT-infected skin. At a later stage of infection (day 7), abscess resolution and bacterial clearance are hindered in ΔfakA mutant-infected mice. The paradoxical findings of decreased Hla in vitro but increased necrosis in vivo led us to investigate the role of the proteases regulated by FakA. Utilizing Δaur and ΔsspAB mutants in both the WT and fakA mutant backgrounds, we found that the absence of these proteases in a fakA mutant reduced dermonecrosis to levels similar to those of the WT strain. These studies suggest that the overproduction of proteases is one factor contributing to the enhanced pathogenesis of the ΔfakA mutant during skin infection.


Subject(s)
Bacterial Proteins/immunology , Metalloendopeptidases/immunology , Phosphotransferases (Carboxyl Group Acceptor)/immunology , Serine Endopeptidases/immunology , Skin Ulcer/immunology , Staphylococcal Skin Infections/immunology , Staphylococcus aureus/pathogenicity , Animals , Bacterial Load , Bacterial Proteins/genetics , Bacterial Toxins/genetics , Bacterial Toxins/immunology , Chemokine CCL4/genetics , Chemokine CCL4/immunology , Female , Gene Expression Regulation , Hemolysin Proteins/genetics , Hemolysin Proteins/immunology , Host-Pathogen Interactions/genetics , Host-Pathogen Interactions/immunology , Interleukin-17/genetics , Interleukin-17/immunology , Interleukin-1alpha/genetics , Interleukin-1alpha/immunology , Interleukin-1beta/genetics , Interleukin-1beta/immunology , Interleukin-6/genetics , Interleukin-6/immunology , Metalloendopeptidases/deficiency , Metalloendopeptidases/genetics , Mice , Phosphotransferases (Carboxyl Group Acceptor)/deficiency , Phosphotransferases (Carboxyl Group Acceptor)/genetics , Serine Endopeptidases/deficiency , Serine Endopeptidases/genetics , Signal Transduction , Skin/immunology , Skin/microbiology , Skin/pathology , Skin Ulcer/genetics , Skin Ulcer/microbiology , Skin Ulcer/pathology , Staphylococcal Skin Infections/genetics , Staphylococcal Skin Infections/microbiology , Staphylococcal Skin Infections/pathology , Staphylococcus aureus/enzymology , Staphylococcus aureus/genetics , Staphylococcus aureus/immunology , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology , Virulence Factors/genetics , Virulence Factors/immunology
17.
Biol Open ; 9(6)2020 06 23.
Article in English | MEDLINE | ID: mdl-32576566

ABSTRACT

Site-1 protease (S1P) ablation in the osterix-lineage in mice drastically reduces bone development and downregulates bone marrow-derived skeletal stem cells. Here we show that these mice also suffer from spina bifida occulta with a characteristic lack of bone fusion in the posterior neural arches. Molecular analysis of bone marrow-derived non-red blood cell cells, via single-cell RNA-Seq and protein mass spectrometry, demonstrate that these mice have a much-altered bone marrow with a significant increase in neutrophils and Ly6C-expressing leukocytes. The molecular composition of bone marrow neutrophils is also different as they express more and additional members of the stefin A (Stfa) family of proteins. In vitro, recombinant Stfa1 and Stfa2 proteins have the ability to drastically inhibit osteogenic differentiation of bone marrow stromal cells, with no effect on adipogenic differentiation. FACS analysis of hematopoietic stem cells show that despite a decrease in hematopoietic stem cells, S1P ablation results in an increased production of granulocyte-macrophage progenitors, the precursors to neutrophils. These observations indicate that S1P has a role in the lineage specification of hematopoietic stem cells and/or their progenitors for development of a normal hematopoietic niche. Our study designates a fundamental requirement of S1P for maintaining a balanced regenerative capacity of the bone marrow niche.


Subject(s)
Hematopoietic Stem Cells/metabolism , Neutrophils/metabolism , Proprotein Convertases/deficiency , Serine Endopeptidases/deficiency , Sp7 Transcription Factor/genetics , Animals , Cell Differentiation/genetics , Cell Lineage/genetics , Gene Expression Profiling , Genetic Association Studies , Hematopoiesis/genetics , Hematopoietic Stem Cells/cytology , Immunophenotyping , Mice , Mice, Knockout , Neutrophils/cytology , Osteogenesis/genetics , Single-Cell Analysis , Spine/anatomy & histology , Spine/diagnostic imaging , Spine/metabolism
19.
Psychiatry Clin Neurosci ; 74(5): 318-327, 2020 May.
Article in English | MEDLINE | ID: mdl-32065683

ABSTRACT

AIM: A Japanese individual with schizophrenia harboring a novel exonic deletion in RELN was recently identified by genome-wide copy-number variation analysis. Thus, the present study aimed to generate and analyze a model mouse to clarify whether Reln deficiency is associated with the pathogenesis of schizophrenia. METHODS: A mouse line with a novel RELN exonic deletion (Reln-del) was established using the CRISPR/Cas9 method to elucidate the underlying molecular mechanism. Subsequently, general behavioral tests and histopathological examinations of the model mice were conducted and phenotypic analysis of the cerebellar granule cell migration was performed. RESULTS: The phenotype of homozygous Reln-del mice was similar to that of reeler mice with cerebellar atrophy, dysplasia of the cerebral layers, and abrogated protein levels of cerebral reelin. The expression of reelin in heterozygous Reln-del mice was approximately half of that in wild-type mice. Conversely, behavioral analyses in heterozygous Reln-del mice without cerebellar atrophy or dysplasia showed abnormal social novelty in the three-chamber social interaction test. In vitro reaggregation formation and neuronal migration were severely altered in the cerebellar cultures of homozygous Reln-del mice. CONCLUSION: The present results in novel Reln-del mice modeled after our patient with a novel exonic deletion in RELN are expected to contribute to the development of reelin-based therapies for schizophrenia.


Subject(s)
Behavior, Animal/physiology , Cell Adhesion Molecules, Neuronal , Cerebellum/pathology , Disease Models, Animal , Extracellular Matrix Proteins , Nerve Tissue Proteins , Neurons/pathology , Schizophrenia/genetics , Serine Endopeptidases , Social Behavior , Animals , Cell Adhesion Molecules, Neuronal/deficiency , Cell Adhesion Molecules, Neuronal/genetics , Cell Adhesion Molecules, Neuronal/metabolism , Exons/genetics , Extracellular Matrix Proteins/deficiency , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Neurologic Mutants , Mice, Transgenic , Nerve Tissue Proteins/deficiency , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Phenotype , Reelin Protein , Schizophrenia/pathology , Schizophrenia/physiopathology , Serine Endopeptidases/deficiency , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism
20.
Inflammation ; 43(3): 1054-1064, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32002713

ABSTRACT

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. Inflammatory pathways contribute to disease pathogenesis; however, regulation of the underlying mechanism is not completely understood. IL-1ß, a pro-inflammatory cytokine, participates in the development and progression of NAFLD. To become bioactive, IL-1ß requires enzymatic processing. Mechanisms that activate IL-1ß include the classical NLRP3 inflammasome-caspase-1 and the neutrophil serine proteases, neutrophil elastase, and proteinase-3. Several studies have shown that both caspase-1 and the neutrophil serine proteases are important for NAFLD development. However, it is unknown whether these pathways interact and if they have a synergistic effect in promoting NAFLD. In the present study, we developed a novel and unique mouse model by intercrossing caspase-1/11 knockout mice with neutrophil elastase/proteinase-3 double knockout mice. Subsequently, these mice were examined regarding the development of high-fat diet-induced NAFLD. Our results show that mice deficient in caspase-1, neutrophil elastase, and proteinase-3 were protected from developing diet-induced weigh gain, liver steatosis, and adipose tissue inflammation when compared with controls. We conclude that pathways that process pro-IL-1ß to bioactive IL-1ß play an important role in promoting the development of NAFLD and obesity-induced inflammation. Targeting these pathways could have a therapeutic potential in patients with NAFLD.


Subject(s)
Caspase 1/deficiency , Interleukin-1beta/antagonists & inhibitors , Leukocyte Elastase/deficiency , Non-alcoholic Fatty Liver Disease/metabolism , Obesity/metabolism , Serine Endopeptidases/deficiency , Animals , Caspase 1/genetics , Diet, High-Fat/adverse effects , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Leukocyte Elastase/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/prevention & control , Obesity/genetics , Obesity/prevention & control , Serine Endopeptidases/genetics
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