Proprotein convertase furin is responsible for the processing of a wide variety of precursors consisted of signal peptide, propeptide and mature peptide in mammal. Many precursors processed by furin have important physiological functions and can be recombinantly expressed in Pichia pastoris expression system for research, pharmaceutical and vaccine applications. However, it is not clear whether the furin cleavage sites between the propeptide and mature peptide can be properly processed in P. pastoris, bringing uncertainty for proper expression of the coding DNA sequences of furin precursors containing the propeptides and mature peptides. In this study, we evaluated the ability of P. pastoris to process furin cleavage sites and how to improve the cleavage efficiencies of furin cleavage sites in P. pastoris. The results showed that P. pastoris can process furin cleavage sites but the cleavage efficiencies are not high. Arg residue at position P1 or P4 in furin cleavage sites significantly affect cleavage
Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children. Success of current therapies is still limited and outcome is particularly poor for metastatic alveolar rhabdomyosarcoma (aRMS). We previously identified the proprotein convertase furin as potential target for specific drug delivery with RMS-homing peptides. Furin is a protease that converts inactive precursor proteins into bioactive proteins and peptides. In this study, we investigate the biological role of furin in aRMS progression in vitro and in vivo. Furin expression was confirmed in over 86% RMS biopsies in a tissue microarray (n=89). Inducible furin silencing in vitro led to significant impairment of cell viability and proliferation in all investigated aRMS cell lines, but not in MRC5 fibroblasts. Furthermore, the aRMS cell lines Rh3 and Rh4 revealed to be very sensitive to furin silencing, undergoing caspase-dependent cell death. Notably, furin silencing in vivo led to complete remission of established Rh4 tumors ...
Matrix metalloproteinases (MMPs), a family of zinc-dependent endopeptidases implicated in tumor invasion and metastasis, must undergo zymogen activation prior to expressing any proteolytic activity. Although the cysteine-switch model predicts the well-established autoactivation process, approximately 40% of the known MMPs possess a conserved RXKR motif between their pro- and catalytic domains and, thus, could be activated directly by members of the proprotein convertase family. To further understand this process, we analyzed the activation of proMT3-MMP as a model system. We demonstrated that the conversion of MT3-MMP zymogen into active form is dependent on both the furin-type convertase activity and the R(116)RKR motif. Consistently, MT3-MMP was colocalized with furin in the trans-Golgi network by confocal microscopy. However, neither furin activity nor its recognition site in MT3-MMP is required for the observed colocalization. In fact, the colocalization pattern remains intact, even in the presence
Glioblastoma is the most common and aggressive intrinsic brain tumor in adults. Self-renewing, highly tumorigenic glioma-initiating cells (GIC) have been linked to glioma invasive properties, immunomodulation, and increased angiogenesis, leading to resistance to therapy. TGF-β signaling has been associated with the tumorigenic activity of GIC. TGF-β is synthesized as a precursor molecule and proteolytically processed to the mature form by members of the family of the proprotein convertases subtilisin/kexin. In this study we report that furin is unique among the proprotein convertases subtilisin/kexin in being highly expressed in human GIC. Furin cleaves and promotes activation of pro-TGF-β1 and pro-TGF-β2, and TGF-β2 in turn increases furin levels. Notably, TGF-β2 controls furin activity in an ALK-5-dependent manner involving the ERK/MAPK pathway. We thus uncover a role of ERK1 in the regulation of furin activity by supporting a self-sustaining loop for high TGF-β activity in GIC. ...
The fusogenic potential of Class I viral envelope glycoproteins is activated by proteloytic cleavage of the precursor glycoprotein to generate the mature receptor-binding and transmembrane fusion subunits. Although the coronavirus (CoV) S glycoproteins share membership in this class of envelope glycoproteins, cleavage to generate the respective S1 and S2 subunits appears absent in a subset of CoV species, including that responsible for the severe acute respiratory syndrome (SARS). To determine whether proteolytic cleavage of the S glycoprotein might be important for the newly emerged SARS-CoV, we introduced a furin recognition site at single basic residues within the putative S1-S2 junctional region. We show that furin cleavage at the modified R667 position generates discrete S1 and S2 subunits and potentiates membrane fusion activity. This effect on the cell-cell fusion activity by the S glycoprotein is not, however, reflected in the infectivity of pseudotyped lentiviruses bearing the cleaved ...
Proteolytic processing is required for the activation of numerous viral glycoproteins. Here we show that the envelope glycoprotein from the Zaire strain of Ebola virus (Ebo-GP) is proteolytically processed into two subunits, GP1 and GP2, that are likely covalently associated through a disulfide linkage. Murine leukemia virions pseudotyped with Ebo-GP contain almost exclusively processed glycoprotein, indicating that this is the mature form of Ebo-GP. Mutational analysis identified a dibasic motif, reminiscent of furin-like protease processing sites, as the Ebo-GP cleavage site. However, analysis of Ebo-GP processing in LoVo cells that lack the proprotein convertase furin demonstrated that furin is not required for processing of Ebo-GP. In sharp contrast to other viral systems, we found that an uncleaved mutant of Ebo-GP was able to mediate infection of various cell lines as efficiently as the wild-type, proteolytically cleaved glycoprotein, indicating that cleavage is not required for the ...
Furin, a subtilisin/kesin-like proprotein convertase (PC), activates membrane-bound MT1-MMP, which facilitates pro-gelatinase A (MMP2). These activated MT1-MMP and MMP2 are involved in cancer cell invasion and metastasis. In this study, we investigate the contribution of MMP2 activated by furin to cellular invasiveness of cumulatively irradiated cells.. Using previously established AMC-HN3 and AMC-HN8 cell line from laryngeal carcinoma patient, we have generated isogenic model of cumulatively irradiated AMC-HN3R and AMC-HN8R cell line, respectively. AMC-HN3R cells were increased furin expression with upregulation of MT1-MMP/MMP2 and their invasiveness by two fold (p , 0.05) compared to AMC-HN3, while AMC-HN8R cells had no differences compared to AMC-HN8. In case of AMC-HN3R, inhibition of furin activity with the synthetic inhibitor decanoyl-Arg-Val-Lys-Arg-chloromethyl-keton, CMK, showed a significant decrease of MT1-MMP/MMP2 and in vitro cellular invasiveness. Tumors obtained after subcutaneous ...
SDS-PAGE studies of EBO virion glycoproteins (Fig. 1 and 3A) and N-terminal sequencing have provided definitive evidence that GP is cleaved (from GP0 form) into two molecules, GP1 and GP2. Cleavage of the structural GP gene product of EBO virus was expected for the N-terminal signal sequence and occurs at the predicted site. Cleavage of GP by furin had been predicted from the RRTRR sequence, but identification of the C-terminal fragment in virions was complicated by its comigration with VP24 in SDS-PAGE. However, prior studies detected GP2 in EBO-infected tissue culture fluids (17, 21), and it was suggested that this uncharacterized glycoprotein might be derived from a cleavage event involving GP. Indirect evidence for furin cleavage of EBO virus GP was recently demonstrated through the use of specific inhibitors of furin activity (21).. When GP sequences of all known EBO viruses are aligned, one finds that the furin cleavage site is conserved but differs slightly from one EBO species to ...
Members of the bacterial Shiga toxin family consist of a single A subunit that is non-covalently associated with a pentamer of B subunits. These toxins bind to receptors on susceptible mammalian cells and enter the cells by endocytic uptake. During cell entry, the 32 kDa A subunit is cleaved by the membrane-anchored protease furin to generate a catalytically active, 27·5 kDa A1 fragment and a 4·5 kDa A2 fragment. Previous studies have shown that mutating the furin site to prevent cleavage did not significantly affect toxin potency, suggesting that cleavage is not required for toxin activity. Here it is confirmed that preventing cleavage at the usual processing site does not prevent proteolytic processing of the Escherichia coli Shiga-like toxin-1 A subunit. However, simultaneous mutation of both the primary furin-recognition site and a nearby putative furin cleavage site did prevent intracellular processing of the A subunit. Comparison of the cytotoxicities of purified recombinant toxins to cultured
Proteases (also called Proteolytic Enzymes, Peptidases, or Proteinases) are enzymes that hydrolyze the amide bonds within proteins or peptides. Most proteases act in a specific manner, hydrolyzing bonds at or adjacent to specific residues or a specific sequence of residues contained within the substrate protein or peptide. Proteases play an important role in most diseases and biological processes including prenatal and postnatal development, reproduction, signal transduction, the immune response, various autoimmune and degenerative diseases, and cancer. They are also an important research tool, frequently used in the analysis and production of proteins. Furin is a calcium dependent serine endoprotease that processes numerous proproteins of different secretory pathways into their mature forms by cleaving at the carboxyl side of the recognition sequence, R-Xaa-(K/R)-R, where Xaa can be any amino acid. Recombinant human Furin is a 61.7 kDa protein, corresponding to residues 124 through 715 of the ...
of Sciences of Ukraine, Kyiv. Received: 22 February 2019; Accepted: 17 May 2019. A series of novel triphenylphosphonium derivatives of 1,3-oxazole containing at C2 and C5-positions electron withdrawing or electron-donating groups were synthesized and characterized by 1H, 31P NMR and IR spectroscopy, element analysis and chromato-mass spectrometry. These compounds were found to be a new class of non-peptide inhibitors of furin. Depending on the chemical structure, they inactivated enzyme at micromolar level by mechanism of competitive, non-competitive or mixed inhibition. Evaluation of the synthesized derivatives as furin inhibitors showed that among the triphenylphosphonium salts studied by us, oxazole 12 containing 2,4-dichlorophenyl- in the C2-position and MeS-group at C5 is the most active (Ki = 1.57 μM) competitive inhibitor of furin. Our results provided evidence that chemical modification of 1,3-oxazole-4-yl-triphenylphosphonium salts may be useful for developing new more potent and ...
This tutorial explains the structure of the spike protein, accompanied by interactive animations of structures determined by cryo-electron microscopy. The furin cleavage site and receptor binding sites are marked. Animations ready for Powerpoint slides are provided. The coronavirus pandemic of 2020 is caused by a virus called SARS-CoV-2. In the electron microscope, it looks like a crown because it has protein "spikes" sticking out. The virus enters and infects cells after its spike protein binds to the ACE2 receptor on cells in the lung or elsewhere. The first step in this binding is "priming", when a protein-cutting enzyme such as furin clips the spike protein. This causes it to stick out its receptor-binding domain, making binding to ACE2 more efficient. Relevant research journal publications are cited. ...
... immune tolerance. portrayed in the growth microenvironment. We present that our healing proteins packed antigenic epitope onto the surface area of mesothelin-expressing growth cells particularly, object rendering tumors prone to antigen-specific cytotoxic Compact disc8+ Testosterone levels lymphocytes (CTL)-mediated eliminating and and and prospects to MHC course I demonstration of Ovum peptide to OVA-specific Compact disc8+ Capital t cells We produced a chimeric antihuman mesothelin scFv (Meso-scFv) conjugated with Fc (IgG2a) proteins made up of ovalbumin (Ovum) peptide flanked by furin cleavage sites (Meso-scFv-ROR-Fc). Physique 1a displays the schematic diagram of chimeric Meso-scFv-ROR-Fc create, control Meso-scFv-Fc proteins without Ovum peptide, and control Meso-scFv-O-Fc proteins without furin cleavage sites. As demonstrated in Physique 1b, just the furin-expressing baby hamster kidney 21 cells transfected ...
The potency of immunotherapies targeting endogenous tumor antigens is impeded by immune tolerance. portrayed in the growth microenvironment. We present that our healing proteins packed antigenic epitope onto the surface area of mesothelin-expressing growth cells particularly, object rendering tumors prone to antigen-specific cytotoxic Compact disc8+ Testosterone levels lymphocytes (CTL)-mediated eliminating and and and prospects to MHC course I demonstration of Ovum peptide to OVA-specific Compact disc8+ Capital t cells We produced a chimeric antihuman mesothelin scFv (Meso-scFv) conjugated with Fc (IgG2a) proteins made up of ovalbumin (Ovum) peptide flanked by furin cleavage sites (Meso-scFv-ROR-Fc). Physique 1a displays the schematic diagram of chimeric Meso-scFv-ROR-Fc create, control Meso-scFv-Fc proteins without Ovum peptide, and control Meso-scFv-O-Fc proteins without furin cleavage sites. As demonstrated in Physique 1b, just the furin-expressing baby hamster kidney 21 cells transfected ...
Furin cleavage assays of fluorogenic peptides. A) Synthetic fluorogenic peptides were generated with sequences matching consensus feline enteric coronavirus and
TY - JOUR. T1 - Evidence for furin-type activity-mediated C-terminal processing of profibrillin-1 and interference in the processing by certain mutations. AU - Lönnqvist, L.. AU - Reinhardt, D.. AU - Sakai, Lynn. AU - Peltonen, L.. PY - 1998/12/1. Y1 - 1998/12/1. N2 - Fibrillin-1 is a major component of the 10 nm microfibrils of the extracellular matrix (ECM). It is synthesized as an ~350 kDa precursor molecule, profibrillin-1, which is proteolytically processed into its biologically active ~320 kDa form. Furin, a calcium-dependent endoprotease of the subtilisin family, which is known to be the processing enzyme for a variety of proproteins, is believed to be responsible for the N-terminal proteolytic cleavage of profibrillin-1. In this article we provide several lines of evidence that the C-terminal trimming of profibrillin-1 also occurs via a furin-type activity. Edman degradation of a small recombinant C-terminal subdomain of fibrillin-1 revealed complete processing of the peptide ...
Two stable cell lines expressing the hBMP2 gene, CHO-BMP2 and HEK-BMP2, were cultured in the presence of IND-1 in short-term (24 h, multi-well) and long-term (two-month, perfusion flasks) cultures. The rhBMP-2 produced was characterized by Western blot and its activity assessed using the C2C12 cell-based assay. The amount of proBMP-2 and mature BMP-2 produced was quantified by ELISA. The mRNA level of BMP-2 and furin in cells treated with or without IND-1 was compared by real-time RT-PCR. Cellular uptake of IND-1 was estimated by measuring the fluorescence of cell lysates following incubation with FITC labeled IND-1. Cellular PC activity post IND-1 incubation was measured using the Boc-RVRR-AMC substrate. Furin-specific siRNA was used to knock down the furin expression in CHO-BMP2 cells and its effect on the rhBMP-2 production was determined. ...
In this study, 48% of the human melanoma cell lines tested were sensitive to PA-L1/LF. Although our studies indicated that modification of the furin cleavage site did slightly reduce PA potency, we have successfully showed the enhanced selectivity of PA-L1/LF. We were able to show that all PA-L1/LF-sensitive melanoma cell lines exhibited high PA-L1 activation as determined by a FRET disruption-based assay (13). Subsequently, we showed that these cell lines exhibited high cell lysate MMP-2 and/or MMP-9 activity. Furthermore, we showed that 11 of 12 PA-L1/LF-sensitive melanoma cell lines carried the B-RAF V600E mutation. In a study including nonmelanoma human tumors, cells carrying this specific mutation were similarly highly susceptible to LF-mediated MAPK inhibition (11). These results show that the B-RAF V600E is closely associated with sensitivity to LF-mediated cell death. Furthermore, small molecular weight inhibitors of MEK1 show similar B-RAF V600E-dependent melanoma cell cytotoxicity ...
Generating a soluble and native-like trimeric envelope glycoprotein (Env) with high efficacy as an immunogen has been a major focus for developing an effective vaccine against HIV-1. The Env immunogen is a heavily glycosylated protein composed of 3 identical surface gp120 and gp41 subunits that form into a trimer o
H5N1, an influenza, binds well onto to &alpha2-3 sialic acid. It contains RNA segments that help produce disease. For example, one RNA segment turns off a component of the immune system. H5 is cleaved by the protease furin, which is present in all cells. Therefore, H5N1 is a pantropic virus able to infect all tissues of avians. It is so pathogenic because, although most human lung cells express α2-6 sialic acid, there are a few expressing α2-3 sialic acid. The H5N1 virus infects these cells and causes a potentially fatal very strong immune response. It can infect poultry, and may adapt to be transmissble from human-to-human. ...
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The second notable feature of SARS-CoV-2 is a polybasic cleavage site (RRAR) at the junction of S1 and S2, the two subunits of the spike8 (Fig. 1b). This allows effective cleavage by furin and other proteases and has a role in determining viral infectivity and host range12. In addition, a leading proline is also inserted at this site in SARS-CoV-2; thus, the inserted sequence is PRRA (Fig. 1b). The turn created by the proline is predicted to result in the addition of O-linked glycans to S673, T678 and S686, which flank the cleavage site and are unique to SARS-CoV-2 (Fig. 1b). Polybasic cleavage sites have not been observed in related lineage B betacoronaviruses, although other human betacoronaviruses, including HKU1 (lineage A), have those sites and predicted O-linked glycans13. Given the level of genetic variation in the spike, it is likely that SARS-CoV-2-like viruses with partial or full polybasic cleavage sites will be discovered in other species.. The functional consequence of the ...
The second notable feature of SARS-CoV-2 is a polybasic cleavage site (RRAR) at the junction of S1 and S2, the two subunits of the spike8 (Fig. 1b). This allows effective cleavage by furin and other proteases and has a role in determining viral infectivity and host range12. In addition, a leading proline is also inserted at this site in SARS-CoV-2; thus, the inserted sequence is PRRA (Fig. 1b). The turn created by the proline is predicted to result in the addition of O-linked glycans to S673, T678 and S686, which flank the cleavage site and are unique to SARS-CoV-2 (Fig. 1b). Polybasic cleavage sites have not been observed in related lineage B betacoronaviruses, although other human betacoronaviruses, including HKU1 (lineage A), have those sites and predicted O-linked glycans13. Given the level of genetic variation in the spike, it is likely that SARS-CoV-2-like viruses with partial or full polybasic cleavage sites will be discovered in other species.. The functional consequence of the ...
The FDA recently announced approval of two cholesterol lowering drugs which both work by inhibiting PCSK9 or proprotein convertase subtilisin/kexin type 9. PCSK9 is an enzyme from the subtilisin-like proprotein convertase family which include proteases that process proteins trafficking through various constitutive secretory pathways. PCSK9 increases blood cholesterol levels by binding to low densitiy lipoprotein (LDL) receptors, targeting them for lysosomal…
The MSLN gene encodes a precursor protein that is cleaved into two products, megakaryocyte potentiating factor (MPF) and mesothelin. Mesothelin is a glycosylphosphatidylinositol (GPI)-anchored cell-surface protein that may function as a cell-adhesion protein. Mesothelin is cleaved by a furin-like protease to yield fragments of approximately 31 kDa and 40 kDa. In humans, mesothelin is overexpressed in epithelial mesotheliomas, ovarian cancers, and in some types of squamous cell carcinomas. The ERC (expressed in renal carcinoma) gene, which was identified in a rat model of renal cancer, has been proposed as a homolog of the human MSLN gene. It plays a role in cell adhesion and shape. Rat mesothelin was also shown to be dynamically expressed in the developing pancreas. In rat and mouse, mesothelin is also known as ERC/mesothelin, protein expressed in renal carcinoma, and pre-pro-megakaryocyte-potentiating factor.. ...
Myostatin, a key regulator of muscle mass in vertebrates, is biosynthesised as a latent precursor in muscle and is activated by sequential proteolysis of the pro-domain. To investigate the molecular mechanism by which pro-myostatin remains latent, we have determined the structure of unprocessed pro-myostatin and analysed the properties of the protein in its different forms. Crystal structures and SAXS analyses show that pro-myostatin adopts an open, V-shaped structure with a domain-swapped arrangement. The pro-mature complex, after cleavage of the furin site, has significantly reduced activity compared with the mature growth factor and persists as a stable complex that is resistant to the natural antagonist follistatin ...
Immunization with Human Papillomavirus (HPV) L1 virus‐like particles or L2 capsid protein elicits neutralizing antibodies that mediate protection
The structure of the precursor of the muscle mass regulator myostatin/GDF8 shows an open‐armed conformation, similar to pro‐activin A and distinct from pro‐TGF‐β1. An enhanced interface between prodomains and the mature growth factor allows pro‐myostatin to persist as a latent, antagonist resistant complex even after processing of the precursor by furin‐like proteases.. ...
Seddon, James A.; Perez-Velez, Carlos M.; Schaaf, H. Simon; Furin, Jennifer J.; Marais, Ben J.; Tebruegge, Marc; Detjen, Anne et al. (Journal of the Pediatric Infectious Diseases Society, 2013) Link to Published Version ...
Feline coronaviruses (FCoV) exist as 2 biotypes: feline enteric coronavirus (FECV) and feline infectious peritonitis virus (FIPV). FECV causes subclinical infections; FIPV causes feline infectious peritonitis (FIP), a systemic and fatal disease. It is thought that mutations in FECV enable infection of macrophages, causing FIP. However, the molecular basis for this biotype switch is unknown. We examined a furin cleavage site in the region between receptor-binding (S1) and fusion (S2) domains of the spike of serotype 1 FCoV. FECV sequences were compared with FIPV sequences. All FECVs had a conserved furin cleavage motif. For FIPV, there was a correlation with the disease and >1 substitution in the S1/S2 motif. Fluorogenic peptide assays confirmed that the substitutions modulate furin cleavage. We document a functionally relevant S1/S2 mutation that arises when FIP develops in a cat. These insights into FIP pathogenesis may be useful in development of diagnostic, prevention, and treatment measures
This gene encodes a member of the subtilisin-like proprotein convertase family, which includes proteases that process protein and peptide precursors trafficking through regulated or constitutive branches of the secretory pathway. The encoded protein undergoes an initial autocatalytic processing event in the ER to generate a heterodimer which exits the ER and sorts to subcellular compartments where a second autocatalytic even takes place and the catalytic activity is acquired. The protease is packaged into and activated in dense core secretory granules and expressed in the neuroendocrine system and brain. This gene encodes one of the seven basic amino acid-specific members which cleave their substrates at single or paired basic residues. It functions in the proteolytic activation of polypeptide hormones and neuropeptides precursors. Mutations in this gene have been associated with susceptibility to obesity and proprotein convertase 1/3 deficiency. Alternatively spliced transcript variants ...
Auriculocondylar syndrome (ACS) is a rare craniofacial disorder with mandibular hypoplasia and question-mark ears (QMEs) as major features. QMEs, consisting of a specific defect at the lobe-helix junction, can also occur as an isolated anomaly. Studies in animal models have indicated the essential role of endothelin 1 (EDN1) signaling through the endothelin receptor type A (EDNRA) in patterning the mandibular portion of the first pharyngeal arch. Mutations in the genes coding for phospholipase C, beta 4 (PLCB4) and guanine nucleotide binding protein (G protein), alpha inhibiting activity polypeptide 3 (GNAI3), predicted to function as signal transducers downstream of EDNRA, have recently been reported in ACS. By whole-exome sequencing (WES), we identified a homozygous substitution in a furin cleavage site of the EDN1 proprotein in ACS-affected siblings born to consanguineous parents. WES of two cases with vertical transmission of isolated QMEs revealed a stop mutation in EDN1 in one family and a ...
TY - JOUR. T1 - Sorting of PC2 to the regulated secretory pathway in AtT20 cells. AU - Taylor, N A. AU - Jan, G. AU - Scougall, K T. AU - Docherty, K. AU - Shennan, K I. PY - 1998/10. Y1 - 1998/10. N2 - PC2 and PC3 are neuroendocrine specific members of the eukaryotic subtilisin-like proprotein convertase (PC) family. Both are sorted via the regulated secretory pathway into secretory granules. In order to identify sequences in PC2 which are involved in targeting to the regulated secretory pathway we expressed a series of PC2 cDNAs containing mutations in the C terminal or propeptide domains in the mouse corticotrophic AtT20 cell line. Sorting of endogenous PC3 was used as a control. PC2 and PC3 were secreted with similar kinetics and sorted to secretory granules with similar efficiencies. Deletions of up to 50 amino acids from the C-terminus of proPC2 had no effect on secretion or sorting, but larger deletions completely prevented maturation or secretion. Two large deletions within the ...
Protein ectodomain shedding is crucial for cell−cell interactions because it controls the bioavailability of soluble tumor necrosis factor-α (TNFα) and ligands of the epidermal growth factor (EGF) receptor, and the release of many other membrane proteins. Various stimuli can rapidly trigger ectodomain shedding, yet much remains to be learned about the identity of the enzymes that respond to these stimuli and the mechanisms underlying their activation. Here, we demonstrate that the membrane-anchored metalloproteinase ADAM17, but not ADAM10, is the sheddase that rapidly responds to the physiological signaling pathways stimulated by thrombin, EGF, lysophosphatidic acid and TNFα. Stimulation of ADAM17 is swift and quickly reversible, and does not depend on removal of its inhibitory pro-domain by pro-protein convertases, or on dissociation of an endogenous inhibitor, TIMP3. Moreover, activation of ADAM17 by physiological stimuli requires its transmembrane domain, but not its cytoplasmic domain, ...
A recent study has shown that Cr-1 controls processing of the Nodal proprotein by recruiting proprotein convertases such as furin or PACE4 (Blanchet et al., 2008). Because processing by furin-like convertases (S1 cleavage) is also a prerequisite to generate mature heterodimerized Notch receptors (Logeat et al., 1998), we hypothesized that CR-1 may affect this processing step. Similar to the sequestration of the Nodal precursor protein into lipid rafts (Blanchet et al., 2008), forced expression of CR-1 in CR-1-deficient CHO cells enhanced the localization of the FL Notch1 protein in the lipid raft fraction in which glycosylphosphatidylinositol-anchored proteins such as CR-1 are enriched (Fig. 4 B). Furthermore, we assessed the effect of CR-1 expression on S1 cleavage of Notch1 in the presence of the γ-secretase inhibitor DAPT to exclude the effect on ligand-induced S3 cleavage (Fig. 4, C and D). CR-1 expression caused a dose-dependent increase in enhancement of the cleaved form of Notch1. This ...
(2003) Rosovitz et al. Journal of Biological Chemistry. A panel of variants with alanine substitutions in the small loop of anthrax toxin protective antigen domain 4 was created to determine individual amino acid residues critical for interactions with ...
Harausz, E.P., Garcia-Prats, A.J., Law, S., Schaaf, H.S., Kredo, T., Seddon, J.A., Menzies, D., Turkova, A., Achar, J., Amanullah, F., Barry, P., Becerra, M., Chan, E.D., Chan, P.C., Ioana Chiotan, D., Crossa, A., Drobac, P.C., Fairlie, L., Falzon, D., Flood, J., Gegia, M., Hicks, R.M., Isaakidis, P., Kadri, S.M., Kampmann, B., Madhi, S.A., Marais, E., Mariandyshev, A., Méndez-Echevarría, A., Moore, B.K., Nargiza, P., Ozere, I., Padayatchi, N., ur-Rehman, S., Rybak, N., Santiago-Garcia, B., Shah, N.S., Sharma, S., Shim, T.S., Skrahina, A., Soriano-Arandes, A., van den Boom, M., van der Werf, M.J., van der Werf, T.S., Williams, B., Yablokova, E., Yim, J.-J., Furin, J., Hesseling, A.C.. ...
Harausz, E.P., Garcia-Prats, A.J., Law, S., Schaaf, H.S., Kredo, T., Seddon, J.A., Menzies, D., Turkova, A., Achar, J., Amanullah, F., Barry, P., Becerra, M., Chan, E.D., Chan, P.C., Ioana Chiotan, D., Crossa, A., Drobac, P.C., Fairlie, L., Falzon, D., Flood, J., Gegia, M., Hicks, R.M., Isaakidis, P., Kadri, S.M., Kampmann, B., Madhi, S.A., Marais, E., Mariandyshev, A., Méndez-Echevarría, A., Moore, B.K., Nargiza, P., Ozere, I., Padayatchi, N., ur-Rehman, S., Rybak, N., Santiago-Garcia, B., Shah, N.S., Sharma, S., Shim, T.S., Skrahina, A., Soriano-Arandes, A., van den Boom, M., van der Werf, M.J., van der Werf, T.S., Williams, B., Yablokova, E., Yim, J.-J., Furin, J., Hesseling, A.C.. ...
The first seven members of the proprotein convertase (PC) family activate protein precursors by cleavage after basic residues. While PC7 has no known specific substrates, it shows redundancy with other PCs. A genome-wide association study suggested t
In an attempt to improve the current live-attenuated vaccine (TC-83) for Venezuelan equine encephalitis (VEE), specific mutations associated with attenuation of VEE virus in rodent models were identified. These mutations were inserted into full-length cDNA clones of the Trinidad donkey strain of VEE virus by site-directed mutagenesis, and isogenic virus strains with these mutations were recovered after transfection of baby hamster kidney cells with infectious RNA. We evaluated 10 of these strains for their ability to replicate in and be transmitted by Aedes taeniorhynchus, a natural vector of epizootic VEE virus. Two vaccine candidates, one containing a deletion of the PE2 furin cleavage site, the other a combination of three separate point mutations in the E2 glycoprotein, replicated in mosquitoes and were transmitted to hamsters significantly less efficiently than was either parental (wild type) VEE virus or TC-83 virus. Although the attenuated strains were transmitted to hamsters by mosquitoes, after
Proteolysis of Precursor proteins regulates many cellular processes like gene expression, embryogenesis, cell cycle, programmed cell death, intracellular protein targeting and endocrine/neural functions. All these processes needs proteolytic cleavage of the precursor protein and in this context this can be done by serine proteases in the secretory pathway. These proteases are calcium dependent serine endoproteases and are related to yeast and subtilisin proteases and therefore called Subtilisin-like Proprotein Convertases (SPCs) or PCs. Till now they identified & characterized seven members of this family in mammals and they have conserved signal peptides, pro-regions, catalytic and P-domains but they differ in C-terminal domains. These proteases get activated by autocatalytic cleavage of an N-terminal propeptide just like Subtilisin which is required for folding and activity. Studies predict that an eight-stranded beta barrel is formed due to folding of the P domain which interacts through a ...
Interaction between bacterial toxins and cellular surface receptors is an important component of host-pathogen interaction. Anthrax toxin protective antigen (PA...
Using a retinoic acid deficiency-induced squamous metaplasia model of HNECs, we observed a significant increase in the expression of PC5/6A, a PC member, and BMP-2, a candidate substrate for PC5/6A. Specific lentiviral shRNA-mediated PC5/6A knockdown decreased BMP-2 expression and maturation, decreased expression of squamous cell markers, and increased expression of ciliated cell markers. Dec-RVKR-CMK, a PC inhibitor, and LDN-193189, a BMP receptor inhibitor, suppressed squamous differentiation, promoted mucociliary differentiation, and down-regulated the BMP-2/Smad1/5/8/p38 signalling pathways. Dec-RVKR-CMK also decreased expression of PC5/6A, but not furin, another PC member, suggesting the involvement of PC5/6A in squamous differentiation of HNECs. Overexpression of PC5/6A and BMP-2 in the human nasal epithelial cell line RPMI-2650 demonstrated that PC5/6A can activate BMP-2. Under retinoic acid-sufficient culture conditions for mucociliary differentiation of HNECs, short-term expression of ...
In terms of sequence homology, CVF is 49% identical to human C3 compared with, for example, 77% sequence identity between human and bovine C3. In combination with the functional and structural similarities between CVF and C3b, we expect that C3b in the AP convertases binds the substrates (C3 and C5) in a manner analogously to how CVF recognizes C5. By further extrapolation-which is justified by the pronounced functional similarities between the AP and the CP convertases-we also expect this to apply to C4b in the CP convertases. We therefore propose a general model for substrate-convertase recognition applicable to both C3 and C5 convertases. In this model, the MG4-MG5 domains of C3b/C4b interact with the MG4-MG5 domains of the substrates C3 and C5 at one interface (the MG4-MG5 interface), while the MG6-MG7 domains of C3b/C4b interact with the substrate MG7 domain at a second interface (the MG7 interface). This proposal is compatible with a variety of experimental results.. With respect to the AP ...
This gene encodes a member of the matrix metalloproteinase family of endopeptidases that are involved in remodeling extracellular matrix during, for example, embryonic development and tumor progression. The encoded protein undergoes post-translational proteolytic processing by furin endopeptidase to form an active enzyme. Subcutaneous introduction of cells expressing the encoded protein into nude mice results in increased tumor incidence. Mice lacking the encoded protein exhibit a decreased incidence of chemically-induced tumors. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2015 ...
K08653 MBTPS1; membrane-bound transcription factor site-1 protease [EC:3.4.21.112] K01349 FURIN; furin [EC:3.4.21.75] K01359 PCSK1; proprotein convertase subtilisin/kexin type 1 [EC:3.4.21.93] K01360 PCSK2; proprotein convertase subtilisin/kexin type 2 [EC:3.4.21.94] K08671 PCSK4; proprotein convertase subtilisin/kexin type 4 [EC:3.4.21.-] K08654 PCSK5; proprotein convertase subtilisin/kexin type 5 [EC:3.4.21.-] K08654 PCSK5; proprotein convertase subtilisin/kexin type 5 [EC:3.4.21.-] K08672 PCSK6; proprotein convertase subtilisin/kexin type 6 [EC:3.4.21.-] K08673 PCSK7; proprotein convertase subtilisin/kexin type 7 [EC:3.4.21.-] K08673 PCSK7; proprotein convertase subtilisin/kexin type 7 [EC:3.4.21.-] K13050 PCSK9; proprotein convertase subtilisin/kexin type 9 [EC:3.4.21.-] K01280 TPP2; tripeptidyl-peptidase II [EC:3.4.14.10 ...
K08653 MBTPS1; membrane-bound transcription factor site-1 protease [EC:3.4.21.112] K01349 FURIN; furin [EC:3.4.21.75] K01359 PCSK1; proprotein convertase subtilisin/kexin type 1 [EC:3.4.21.93] K01360 PCSK2; proprotein convertase subtilisin/kexin type 2 [EC:3.4.21.94] K08654 PCSK5; proprotein convertase subtilisin/kexin type 5 [EC:3.4.21.-] K08672 PCSK6; proprotein convertase subtilisin/kexin type 6 [EC:3.4.21.-] K08673 PCSK7; proprotein convertase subtilisin/kexin type 7 [EC:3.4.21.-] K13050 PCSK9; proprotein convertase subtilisin/kexin type 9 [EC:3.4.21.-] K01280 TPP2; tripeptidyl-peptidase II [EC:3.4.14.10 ...
The processing mechanism and gelatinolytic activity of the membrane-type matrix metalloproteinase 1 (MT-MMP-1) were examined by expressing in COS-1 cells a deletion mutant of MT-MMP-1 lacking the trans-membrane domain (delta MT1) and its site-directed mutant with a furin-resistant sequence in the propeptide domain (mutant delta MT1). delta MT1, but not mutant delta MT1, was processed to an active form and exhibited gelatinolytic activity as seen using gelatin zymography. delta MT1 isolated in a complex form with tissue inhibitor of metalloproteinases 2 (TIMP-2) from the stable transfectants demonstrated the NH2-terminal sequence of Ala113-IIe-Gln-Leu, indicating cleavage at one amino acid down-stream from the furin recognition sequence. The delta MT1/TIMP-2 complex formed a ternary complex with proMMP-2 through the COOH termini of TIMP-2 and proMMP-2. A human breast carcinoma cell line (MDA-MB-231 cells) also secreted MT-MMP-1 into culture media, which was purified in a complex form with TIMP-2 and