scholarly journals P029 TRIM 21 protects against ulcerative colitis and colitic cancer via smad7 inhibition

2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S146-S146
Author(s):  
K B Hahm
Keyword(s):  
Ulcerative Colitis ◽  
Coiled Coil ◽  
Type I ◽  
Typical Structure ◽  
Th17 Cell Differentiation ◽  
Bowel Diseases ◽  
Colitic Cancer ◽  
Β Receptor ◽  
Trim Proteins

Abstract Background Proteins of the tripartite motif-containing (TRIM) superfamily are critical in a variety of biological processes in either innate immunity or eliminating invading pathogens, by which had been implicated in pathogenesis of autoimmune diseases including inflammatory bowel diseases. The typical structure of TRIM proteins contains a RING motif in the N-terminal end, followed by a B-box motif, a coiled-coil domain and a B30.2/PRYSPRY region in the C-terminal end led to the regulation of TGF-β anti-inflammatory cytokines, by which TRIM21 has been reported to regulate IBD negatively through inhibiting Th1/Th17 cell differentiation. Methods Since antisense oligonucleotide targeting smad7 was withdrawn from clinical trial due to insufficient efficacy, in this study, we generated TRIM21 overexpressed cell lines to study the binding of TRIM21 to smad7 as well as the regulation of consequent TGF-β receptor. Results TRIM21 significantly binds to smad7 as well as repressed levels of TGF-b type I/II receptor. SBE-luc and 3TP-luc assay showed significantly decreased activities under TRIM21 + TGF-β. Since TRIM21 contains ubiquitin ligase, PRYSPRY, TRIM21 with TGF-β significantly decreased TGFRII via UPL. These in vitro evidences that TRIM21 significantly repressed TGF-β after binding smad7 were validated with DSS-induced colitis and colitic cancer model. TRIM21 was significantly decreased in DSS-induced ulcerative colitis, whereas ameliorated colitis showed significant restoration of TRIM21 Conclusion Leading to conclusion that loss of TRIM21 led to significant bout of IBD.

scholarly journals Site-specific ubiquitination exposes a linear motif to promote interferon-α receptor endocytosis

2007 ◽  
Vol 179 (5) ◽  
pp. 935-950 ◽  
Author(s):  
K.G. Suresh Kumar ◽  
Hervé Barriere ◽  
Christopher J. Carbone ◽  
Jianghuai Liu ◽  
Gayathri Swaminathan ◽  
...  
Keyword(s):  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
Interferon Α ◽  
Type I ◽  
Lysosomal Degradation ◽  
Linear Motif ◽  
Site Specific ◽  
Receptor Endocytosis ◽  
Β Receptor

Ligand-induced endocytosis and lysosomal degradation of cognate receptors regulate the extent of cell signaling. Along with linear endocytic motifs that recruit the adaptin protein complex 2 (AP2)–clathrin molecules, monoubiquitination of receptors has emerged as a major endocytic signal. By investigating ubiquitin-dependent lysosomal degradation of the interferon (IFN)-α/β receptor 1 (IFNAR1) subunit of the type I IFN receptor, we reveal that IFNAR1 is polyubiquitinated via both Lys48- and Lys63-linked chains. The SCFβTrcp (Skp1–Cullin1–F-box complex) E3 ubiquitin ligase that mediates IFNAR1 ubiquitination and degradation in cells can conjugate both types of chains in vitro. Although either polyubiquitin linkage suffices for postinternalization sorting, both types of chains are necessary but not sufficient for robust IFNAR1 turnover and internalization. These processes also depend on the proximity of ubiquitin-acceptor lysines to a linear endocytic motif and on its integrity. Furthermore, ubiquitination of IFNAR1 promotes its interaction with the AP2 adaptin complex that is required for the robust internalization of IFNAR1, implicating cooperation between site-specific ubiquitination and the linear endocytic motif in regulating this process.

Use of Synbiotics for Ulcerative Colitis Treatment

2020 ◽  
Vol 15 (3) ◽  
pp. 174-182 ◽  
Author(s):  
Marianna Roselli ◽  
Alberto Finamore
Keyword(s):  
Ulcerative Colitis ◽  
Gastrointestinal Tract ◽  
Intestinal Microbiota ◽  
Strong Impact ◽  
Beneficial Effects ◽  
System A ◽  
Bowel Diseases ◽  
Ulcerative Colitis Treatment ◽  
Inflammatory Bowel

Inflammatory bowel diseases, namely Crohn's disease and ulcerative colitis, are currently considered multifactorial pathologies in which various combined environmental factors act on genetic background, giving rise to chronic inflammation of the gastrointestinal tract. Ulcerative colitis is an inflammation of the colon caused by a dysregulated immune response to host intestinal microbiota in genetically susceptible subjects. Ulcerative colitis has a strong impact on patients' quality of life, as well as high costs for the health-care system. A great interest on the role of intestinal microbiota modulation in ulcerative colitis is emerging. Several studies have shown an improvement of inflammatory markers and symptoms in ulcerative colitis patients through treatments with probiotics and prebiotics separately. Despite the low number of studies on the treatment of ulcerative colitis by specific strains of probiotics plus selected prebiotics, i.e. synbiotics, the results are promising, even if discordant. The mechanism of action in synbiotics supplementation is still unclear and needs more investigation, although there is a large number of data indicating that the synergism between probiotics and prebiotics favours the survival and implantation of probiotics into the gastrointestinal tract with beneficial effects on human health by modulating the inflammatory response and gut microbiota composition. The aim of this minireview is to describe the main in vitro, animal and human studies performed up to now, that have used synbiotics to treat ulcerative colitis, and to highlight limitations and future perspectives.

scholarly journals Identification of protein IT of the intestinal cytoskeleton as a novel type I cytokeratin with unusual properties and expression patterns.

1990 ◽  
Vol 111 (2) ◽  
pp. 567-580 ◽  
Author(s):  
R Moll ◽  
D L Schiller ◽  
W W Franke
Keyword(s):  
Mammalian Species ◽  
Expression Patterns ◽  
Prostate Gland ◽  
Coiled Coil ◽  
Immunological Methods ◽  
Type I ◽  
Peptide Fragments ◽  
Binding Assays ◽  
Human Intestinal Epithelium

A major cytoskeletal polypeptide (Mr approximately 46,000; protein IT) of human intestinal epithelium was characterized by biochemical and immunological methods. The polypeptide, which was identified as a specific and genuine mRNA product by translation in vitro, reacted, in immunoblotting after SDS-PAGE, only with one of numerous cytokeratin (CK) antisera tested but with none of many monoclonal CK antibodies. In vitro, it formed heterotypic complexes with the type II CK 8, as shown by blot binding assays and gel electrophoresis in 4 M urea, and these complexes assembled into intermediate filaments (IFs) under appropriate conditions. A chymotrypsin-resistant Mr approximately 38,000 core fragment of protein IT could be obtained from cytoskeletal IFs, indicating its inclusion in a coiled coil. Antibodies raised against protein IT decorated typical CK fibril arrays in normal and transformed intestinal cells. Four proteolytic peptide fragments obtained from purified polypeptide IT exhibited significant amino acid sequence homology with corresponding regions of coils I and II of the rod domain of several other type I CKs. Immunocytochemically, the protein was specifically detected as a prominent component of intestinal and gastric foveolar epithelium, urothelial umbrella cells, and Merkel cells of epidermis. Sparse positive epithelial cells were noted in the thymus, bronchus, gall bladder, and prostate gland. The expression of protein IT was generally maintained in primary and metastatic colorectal carcinomas as well as in cell cultures derived therefrom. A corresponding protein was also found in several other mammalian species. We conclude that polypeptide IT is an integral IF component which is related, though somewhat distantly, to type I CKs, and, therefore, we propose to add it to the human CK catalogue as CK 20.

scholarly journals Regulation of TGF-β receptor hetero-oligomerization and signaling by endoglin

2015 ◽  
Vol 26 (17) ◽  
pp. 3117-3127 ◽  
Author(s):  
Leslie Pomeraniec ◽  
Melissa Hector-Greene ◽  
Marcelo Ehrlich ◽  
Gerard C. Blobe ◽  
Yoav I. Henis
Keyword(s):  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Cell Surface Receptor ◽  
Live Cells ◽  
Type I ◽  
Intact Cells ◽  
Surface Receptor ◽  
Β Receptor ◽  
Complex Signaling

Complex formation among transforming growth factor-β (TGF-β) receptors and its modulation by coreceptors represent an important level of regulation for TGF-β signaling. Oligomerization of ALK5 and the type II TGF-β receptor (TβRII) has been thoroughly investigated, both in vitro and in intact cells. However, such studies, especially in live cells, are missing for the endothelial cell coreceptor endoglin and for the ALK1 type I receptor, which enables endothelial cells to respond to TGF-β by activation of both Smad2/3 and Smad1/5/8. Here we combined immunoglobulin G–mediated immobilization of one cell-surface receptor with lateral mobility studies of a coexpressed receptor by fluorescence recovery after photobleaching (FRAP) to demonstrate that endoglin forms stable homodimers that function as a scaffold for binding TβRII, ALK5, and ALK1. ALK1 and ALK5 bind to endoglin with differential dependence on TβRII, which plays a major role in recruiting ALK5 to the complex. Signaling data indicate a role for the quaternary receptor complex in regulating the balance between TGF-β signaling to Smad1/5/8 and to Smad2/3.

scholarly journals LY2109761, Transforming Growth Factor β Receptor Type I and Type II Dual Inhibitor, is a Novel Approach to Suppress Endothelial Mesenchymal Transformation in Human Corneal Endothelial Cells

2018 ◽  
Vol 50 (3) ◽  
pp. 963-972 ◽  
Author(s):  
Zhi-hua Zhang ◽  
Yu-yu Miao ◽  
Bi-lian Ke ◽  
Kun Liu ◽  
Xun Xu
Keyword(s):  
Receptor Type ◽  
Functional Markers ◽  
Type I ◽  
Type Ii ◽  
Corneal Endothelial Cells ◽  
Dual Inhibitor ◽  
In Vitro Expansion ◽  
Β Receptor ◽  
Mesenchymal Transformation

Background/Aims: Preventing undesirable endothelial-mesenchymal transformation (EnMT) with repetitious in vitro expansion of human corneal endothelial cells (CECs) is a pivotal issue in cornea regeneration. Previous studies have shown that inhibition of the TGF-β pathway reduces epithelial-mesenchymal transformation. However, its potential role in EnMT remains poorly understood. As such, the effect of LY2109761, a novel TGF-β receptor type I and type II dual inhibitor, was investigated on EnMT. Methods: CECs cultured with various concentrations of LY2109761 were evaluated for their growth rate and phenotype. Additionally, the expression of functional markers (sodium-potassium pump Na+/K+-ATPase and the tight junction protein ZO-1) and mesenchymal markers (CD73, fibronectin, and vimentin) was detected using immunostaining and western blot. The mRNA expressions were also assayed by real-time polymerase chain reaction analysis. Results: At a 1 μM concentration, LY2109761 did not influence the proliferation of CECs and subsequent experiments were therefore performed using this concentration. Furthermore, CECs cultured in the presence of 1 μM LY2109761 maintained their ability to grow as a monolayer of hexagonal-shaped cells. The expression of functional markers increased in LY2109761-treated CECs, while the expression of mesenchymal markers decreased (both in protein and mRNA levels). Conclusion: Inhibition of TGF-β receptor type I and type II by LY2109761 maintained the phenotype of CECs and inhibited the EnMT process. These results indicate the possible continuous in vitro expansion of CECs with normal function.

TGF-β signaling promotes survival and repair in rat alveolar epithelial type 2 cells during recovery after hyperoxic injury

2008 ◽  
Vol 294 (4) ◽  
pp. L739-L748 ◽  
Author(s):  
S. Buckley ◽  
W. Shi ◽  
L. Barsky ◽  
D. Warburton
Keyword(s):  
Dna Damage ◽  
Transforming Growth Factor ◽  
Type I ◽  
Alveolar Epithelial ◽  
Repair Activity ◽  
A Cell ◽  
Β Receptor ◽  
Tgf Β1

Hyperoxic rats treated with inosine during oxygen exposure have increased levels of active transforming growth factor (TGF)-β in the bronchoalveolar lavage (BAL), yet alveolar epithelial type 2 cells (AEC2) isolated from these animals demonstrate less hyperoxia-induced DNA damage and increased expression of active Smad2. To determine whether TGF-β1 signaling per se protected AEC2 against hyperoxic damage, freshly isolated AEC2 from hyperoxic rats were incubated with TGF-β1 for 24 h and assayed for DNA damage by fluorescein-activated cell sorter analysis of TdT-mediated dUTP nick end labeling. TGF-β1 was protective over a concentration range similar to that in BAL of inosine-treated hyperoxic animals (50–5,000 pg/ml). TGF-β1 also augmented hyperoxia-induced DNA repair activity and cell migration, stimulated autocrine secretion of fibronectin, accelerated closure of a monolayer scratch wound, and restored hyperoxia-depleted VEGF secretion by AEC2 to normoxic levels. The TGF-β receptor type I activin-like kinase-4, -5, and -7 inhibitor peptide SB-505124 abolished the protective effect of TGF-β on hyperoxic DNA damage and increased TdT-mediated dUTP nick end labeling in normoxic cells. These data suggest that endogenous TGF-β-mediated Smad signaling is required for AEC2 homeostasis in vitro, while exogenous TGF-β1 treatment of hyperoxia-damaged AEC2 results in a cell that is equipped to survive, repair, migrate, secrete matrix, and induce new blood vessel formation more efficiently than AEC2 primed by hyperoxia alone.

scholarly journals An unusual intermediate filament subunit from the cytoskeletal biopolymer released extracellularly into seawater by the primitive hagfish (Eptatretus stouti)

1994 ◽  
Vol 107 (11) ◽  
pp. 3133-3144 ◽  
Author(s):  
E.A. Koch ◽  
R.H. Spitzer ◽  
R.B. Pithawalla ◽  
D.A. Parry
Keyword(s):  
Intermediate Filament ◽  
Coiled Coil ◽  
Total Content ◽  
Data Bank ◽  
Peripheral Region ◽  
Amino Acid Sequences ◽  
Type I ◽  
10 Nm Filaments ◽  
Terminal Domains

Each slime gland thread cell from the primitive Pacific hagfish (Eptatretus stouti) contains a massive, conical, intermediate filament (IF)-rich biopolymer (‘thread,’ approximately 60 cm length, approximately 3 microns width). In view of the unusual ultrastructure of the thread, its extracellular role in modulation of the viscoelastic properties of mucus, and the ancient lineage of this primitive vertebrate, we report the nucleotide and deduced amino acid sequences of one major thread IF subunit, alpha (pI 7.5), which is coexpressed with a second polypeptide, gamma (pI 5.3). These two polypeptides coassemble in vitro into approximately 10 nm filaments. The alpha-thread chain, a 66.6 kDa polypeptide, has an unusual central rod domain containing 318 residues flanked by N- and C-terminal domains of 192 and 133 residues, respectively. Each peripheral region exhibits some epidermal keratin-like features including peptide repeats and a high total content of glycine and serine residues. The terminal domains, however, lack the H1 and H2 subdomains characteristic of known keratins. Moreover, when the central rod is aligned either in relation to established homology profiles (J. F. Conway and D. A. D. Parry (1988) Int. J. Biol. Macromol. 10, 79–98) of other IF subunits (types I-V, nestin, non-neuronal invertebrate), or by computer-based homology searches of the GenBank/EMBL Data Bank, a low identity (< 30%) is evident, with no preferred identity to keratins or other known IF types. Although the central rod of 318 residues consists of the canonical apolar heptad repeats interspersed with three linker regions, a discontinuity in phasing of the heptad substructure in rod 2B, and conserved sequences at either end of the rod domain, other collective characteristics are atypical: overall high threonine content (13.2% vs 2.3-5.4% for other IFs), high threonine content in rod 1B (18.8% vs 1–6%), five Thr-Thr repeats in coiled coil segments, L12 of length greater than in keratins, substitution of phenylalanine for a highly conserved glutamate in the sixth position of L2, and a glycine-proline sequence in segment 2B. Possibly as a result of the high threonine content, the percentage of both acidic and basic residues in most helical subdomains is reduced relative to type I and II chains. Fast Fourier transform analyses show that only the acidic residues in segment 1B and basic residues in segment 2 have near typical IF periods.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Do the ends justify the mean? Proline mutations at the ends of the keratin coiled-coil rod segment are more disruptive than internal mutations.

1992 ◽  
Vol 116 (5) ◽  
pp. 1181-1195 ◽  
Author(s):  
A Letai ◽  
P A Coulombe ◽  
E Fuchs
Keyword(s):  
Amino Acid ◽  
Amino Acid Residue ◽  
Network Formation ◽  
Coiled Coil ◽  
Type I ◽  
Cellular Interactions ◽  
Filament Assembly ◽  
Filament Network

Intermediate filament (IF) assembly is remarkable, in that it appears to be self-driven by the primary sequence of IF proteins, a family (40-220 kd) with diverse sequences, but similar secondary structures. Each IF polypeptide has a central 310 amino acid residue alpha-helical rod domain, involved in coiled-coil dinner formation. Two short (approximately 10 amino acid residue) stretches at the ends of this rod are more highly conserved than the rest, although the molecular basis for this is unknown. In addition, the rod is segmented by three short nonhelical linkers of conserved location, but not sequence. To examine the degree to which different conserved helical and nonhelical rod sequences contribute to dimer, tetramer, and higher ordered interactions, we introduced proline mutations in residues throughout the rod of a type I keratin, and we removed existing proline residues from the linker regions. To further probe the role of the rod ends, we introduced more subtle mutations near the COOH-terminus. We examined the consequences of these mutations on (a) IF network formation in vivo, and (b) 10-nm filament assembly in vitro. Surprisingly, all proline mutations located deep in the coiled-coil rod segment showed rather modest effects on filament network formation and 10-nm filament assembly. In addition, removing the existing proline residues was without apparent effect in vivo, and in vitro, these mutants assembled into 10-nm filaments with a tendency to aggregate, but with otherwise normal appearance. The most striking effects on filament network formation and IF assembly were observed with mutations at the very ends of the rod. These data indicate that sequences throughout the rod are not equal with respect to their role in filament network formation and in 10-nm filament assembly. Specifically, while the internal rod segments seem able to tolerate considerable changes in alpha-helical conformation, the conserved ends seem to be essential for creating a very specific structure, in which even small perturbations can lead to loss of IF stability and disruption of normal cellular interactions. These findings have important implications for the disease Epidermolysis Bullosa Simplex, arising from point mutations in keratins K5 or K14.

scholarly journals The stem cell markerProm1promotes axon regeneration by down-regulating cholesterol synthesis via Smad signaling

2020 ◽  
Vol 117 (27) ◽  
pp. 15955-15966 ◽  
Author(s):  
Jinyoung Lee ◽  
Jung Eun Shin ◽  
Bohm Lee ◽  
Hyemin Kim ◽  
Yewon Jeon ◽  
...  
Keyword(s):  
Stem Cell ◽  
Axon Regeneration ◽  
Cholesterol Metabolism ◽  
Stem Cell Marker ◽  
Type I ◽  
Dependent Manner ◽  
Axonal Regrowth ◽  
Β Receptor

Axon regeneration is regulated by a neuron-intrinsic transcriptional program that is suppressed during development but that can be reactivated following peripheral nerve injury. Here we identifyProm1, which encodes the stem cell marker prominin-1, as a regulator of the axon regeneration program.Prom1expression is developmentally down-regulated, and the genetic deletion ofProm1in mice inhibits axon regeneration in dorsal root ganglion (DRG) cultures and in the sciatic nerve, revealing the neuronal role ofProm1in injury-induced regeneration. Elevating prominin-1 levels in cultured DRG neurons or in mice via adeno-associated virus-mediated gene delivery enhances axon regeneration in vitro and in vivo, allowing outgrowth on an inhibitory substrate.Prom1overexpression induces the consistent down-regulation of cholesterol metabolism-associated genes and a reduction in cellular cholesterol levels in a Smad pathway-dependent manner, which promotes axonal regrowth. We find that prominin-1 interacts with the type I TGF-β receptor ALK4, and that they synergistically induce phosphorylation of Smad2. These results suggest thatProm1and cholesterol metabolism pathways are possible therapeutic targets for the promotion of neural recovery after injury.

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