scholarly journals Linear Ubiquitin Code: Its Writer, Erasers, Decoders, Inhibitors, and Implications in Disorders

2020 ◽  
Vol 21 (9) ◽  
pp. 3381 ◽  
Author(s):  
Daisuke Oikawa ◽  
Yusuke Sato ◽  
Hidefumi Ito ◽  
Fuminori Tokunaga
Keyword(s):  
Ubiquitin Ligase ◽  
Specific Binding ◽  
Nuclear Factor Κb ◽  
Innate Immune Responses ◽  
Deubiquitinating Enzymes ◽  
Ubiquitin Chain ◽  
Interacting Protein ◽  
Binding Domains ◽  
Ubiquitination Pathway ◽  
And Control

The linear ubiquitin chain assembly complex (LUBAC) is a ubiquitin ligase composed of the Heme-oxidized IRP2 ubiquitin ligase-1L (HOIL-1L), HOIL-1L-interacting protein (HOIP), and Shank-associated RH domain interactor (SHARPIN) subunits. LUBAC specifically generates the N-terminal Met1-linked linear ubiquitin chain and regulates acquired and innate immune responses, such as the canonical nuclear factor-κB (NF-κB) and interferon antiviral pathways. Deubiquitinating enzymes, OTULIN and CYLD, physiologically bind to HOIP and control its function by hydrolyzing the linear ubiquitin chain. Moreover, proteins containing linear ubiquitin-specific binding domains, such as NF-κB-essential modulator (NEMO), optineurin, A20-binding inhibitors of NF-κB (ABINs), and A20, modulate the functions of LUBAC, and the dysregulation of the LUBAC-mediated linear ubiquitination pathway induces cancer and inflammatory, autoimmune, and neurodegenerative diseases. Therefore, inhibitors of LUBAC would be valuable to facilitate investigations of the molecular and cellular bases for LUBAC-mediated linear ubiquitination and signal transduction, and for potential therapeutic purposes. We identified and characterized α,β-unsaturated carbonyl-containing chemicals, named HOIPINs (HOIP inhibitors), as LUBAC inhibitors. We summarize recent advances in elucidations of the pathophysiological functions of LUBAC-mediated linear ubiquitination and identifications of its regulators, toward the development of LUBAC inhibitors.

scholarly journals LUBAC Formation Is Impaired in the Livers of Mice with MCD-Dependent Nonalcoholic Steatohepatitis

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Yasuka Matsunaga ◽  
Yusuke Nakatsu ◽  
Toshiaki Fukushima ◽  
Hirofumi Okubo ◽  
Misaki Iwashita ◽  
...  
Keyword(s):  
Ubiquitin Ligase ◽  
Nonalcoholic Steatohepatitis ◽  
Molecular Mechanisms ◽  
Regulatory Protein ◽  
Gel Filtration ◽  
Native Page ◽  
Ubiquitin Chain ◽  
Interacting Protein ◽  
Hepatic Lipid Accumulation ◽  
Pathway Activation

Nonalcoholic steatohepatitis (NASH) is a disorder characterized by hepatic lipid accumulation followed by the inflammation-induced death of hepatocytes and fibrosis. In this process, oxidative stress contributes to the induction of several inflammatory cytokines including TNF-αand　IL-1βin macrophages, while, in hepatocytes, NF-κB reportedly induces the expressions of cell survival genes for protection from apoptosis. Recently, it was reported that the new ubiquitin ligase complex termed linear ubiquitin chain assembly complex (LUBAC), composed of SHARPIN (SHANK-associated RH domain-interacting protein), HOIL-1L (longer isoform of heme-oxidized iron-regulatory protein 2 ubiquitin ligase-1), and HOIP (HOIL-1L interacting protein), forms linear ubiquitin on NF-κB essential modulator (NEMO) and thereby induces NF-κB pathway activation. In this study, we demonstrated the formation of LUBAC to be impaired in the livers of NASH rodent models produced by methionine and choline deficient (MCD) diet feeding, first by either gel filtration or Blue Native-PAGE, with subsequent confirmation by western blotting. The reduction of LUBAC is likely to be attributable to markedly reduced expression of SHARPIN, one of its components. Thus, impaired LUBAC formation, which would result in insufficient NF-κB activation, may be one of the molecular mechanisms underlying the enhanced apoptotic response of hepatocytes in MCD diet-induced NASH livers.

scholarly journals Crosstalk Between NDP52 and LUBAC in Innate Immune Responses, Cell Death, and Xenophagy

2021 ◽  
Vol 12 ◽  
Author(s):  
Hirohisa Miyashita ◽  
Daisuke Oikawa ◽  
Seigo Terawaki ◽  
Daijiro Kabata ◽  
Ayumi Shintani ◽  
...  
Keyword(s):  
Immune Responses ◽  
Hela Cells ◽  
Nuclear Factor Κb ◽  
Suppressive Effect ◽  
Innate Immune ◽  
Bacterial Invasion ◽  
Innate Immune Responses ◽  
Apoptotic Pathway ◽  
Ubiquitin Chain ◽  
Tnf Α

Nuclear dot protein 52 kDa (NDP52, also known as CALCOCO2) functions as a selective autophagy receptor. The linear ubiquitin chain assembly complex (LUBAC) specifically generates the N-terminal Met1-linked linear ubiquitin chain, and regulates innate immune responses, such as nuclear factor-κB (NF-κB), interferon (IFN) antiviral, and apoptotic pathways. Although NDP52 and LUBAC cooperatively regulate bacterial invasion-induced xenophagy, their functional crosstalk remains enigmatic. Here we show that NDP52 suppresses canonical NF-κB signaling through the broad specificity of ubiquitin-binding at the C-terminal UBZ domain. Upon TNF-α-stimulation, NDP52 associates with LUBAC through the HOIP subunit, but does not disturb its ubiquitin ligase activity, and has a modest suppressive effect on NF-κB activation by functioning as a component of TNF-α receptor signaling complex I. NDP52 also regulates the TNF-α-induced apoptotic pathway, but not doxorubicin-induced intrinsic apoptosis. A chemical inhibitor of LUBAC (HOIPIN-8) cancelled the increased activation of the NF-κB and IFN antiviral pathways, and enhanced apoptosis in NDP52-knockout and -knockdown HeLa cells. Upon Salmonella-infection, colocalization of Salmonella, LC3, and linear ubiquitin was detected in parental HeLa cells to induce xenophagy. Treatment with HOIPIN-8 disturbed the colocalization and facilitated Salmonella expansion. In contrast, HOIPIN-8 showed little effect on the colocalization of LC3 and Salmonella in NDP52-knockout cells, suggesting that NDP52 is a weak regulator in LUBAC-mediated xenophagy. These results indicate that the crosstalk between NDP52 and LUBAC regulates innate immune responses, apoptosis, and xenophagy.

Tanshinone IIA attenuates elastase-induced AAA in rats via inhibition of MyD88-dependent TLR-4 signaling

VASA ◽  
2014 ◽  
Vol 43 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Tao Shang ◽  
Feng Ran ◽  
Qian Qiao ◽  
Zhao Liu ◽  
Chang-Jian Liu
Keyword(s):  
Nuclear Factor Κb ◽  
Tanshinone Iia ◽  
Myeloid Differentiation ◽  
Aortic Tissue ◽  
Toll Like Receptor ◽  
Sprague Dawley ◽  
Toll Like Receptor 4 ◽  
Tissue Samples ◽  
Myeloid Differentiation Factor ◽  
And Control

Background: The purpose of this study was to determine whether myeloid differentiation factor88-dependent Toll-Like Receptor-4 (TLR-4) signaling contributed to the inhibition of abdominal aortic aneurysm (AAA) by Tanshinone IIA (Tan IIA). Materials and methods: Male Sprague-Dawley rats (n = 12 / group) were randomly distributed into three groups: Tan IIA, control, and sham. The rats from Tan IIA and control groups under-went intra-aortic elastase perfusion to induce AAAs, and those in the sham group were perfused with saline. Only the Tan IIA group received Tan IIA (2 mg / rat / d). Aortic tissue samples were harvested at 24 d after perfusion and evaluated using reverse transcriptase-polymerase chain reaction, Western blot, immunohistochemistry and immunofluorescence. Results: The over-expression of Toll-Like Receptor-4 (TLR-4), Myeloid Differentiation factor 88 (MyD88), Phosphorylated Nuclear Factor κB (pNF-κB) and Phosphorylated IκBα (pIκBα) induced by elastase perfusion were significantly decreased by Tan IIA treatment. Conclusions: Tan IIA attenuates elastase-induced AAA in rats possibly via the inhibition of MyD88-dependent TLR-4 signaling, which may be one potential explanation of why Tan IIA inhibits AAA development through multiple effects.

scholarly journals Engineering of Bio-Adhesive Ligand Containing Recombinant RGD and PHSRN Fibronectin Cell-Binding Domains in Fusion with a Colored Multi Affinity Tag: Simple Approach for Fragment Study from Expression to Adsorption

2021 ◽  
Vol 22 (14) ◽  
pp. 7362
Author(s):  
Amina Ben Abla ◽  
Guilhem Boeuf ◽  
Ahmed Elmarjou ◽  
Cyrine Dridi ◽  
Florence Poirier ◽  
...  
Keyword(s):  
Specific Binding ◽  
Cellular Adhesion ◽  
High Yield ◽  
Adhesion Assay ◽  
Cell Binding ◽  
Affinity Tag ◽  
Binding Domains ◽  
Rational Development ◽  
Fibronectin Type Iii ◽  
Arginine Glycine Aspartic Acid

Engineering of biomimetic motives have emerged as promising approaches to improving cells’ binding properties of biomaterials for tissue engineering and regenerative medicine. In this study, a bio-adhesive ligand including cell-binding domains of human fibronectin (FN) was engineered using recombinant protein technology, a major extracellular matrix (ECM) protein that interacts with a variety of integrins cell-surface’s receptors and other ECM proteins through specific binding domains. 9th and 10th fibronectin type III repeat containing Arginine-Glycine-Aspartic acid (RGD) and Pro-His-Ser-Arg-Asn (PHSRN) synergic site (FNIII9-10) were expressed in fusion with a Colored Multi Affinity Tag (CMAT) to develop a simplified production and characterization process. A recombinant fragment was produced in the bacterial system using E. coli with high yield purified protein by double affinity chromatography. Bio-adhesive surfaces were developed by passive coating of produced fragment onto non adhesive surfaces model. The recombinant fusion protein (CMAT-FNIII9/10) demonstrated an accurate monitoring capability during expression purification and adsorption assay. Finally, biological activity of recombinant FNIII9/10 was validated by cellular adhesion assay. Binding to α5β1 integrins were successfully validated using a produced fragment as a ligand. These results are robust supports to the rational development of bioactivation strategies for biomedical and biotechnological applications.

scholarly journals Essential role of IPS-1 in innate immune responses against RNA viruses

2006 ◽  
Vol 203 (7) ◽  
pp. 1795-1803 ◽  
Author(s):  
Himanshu Kumar ◽  
Taro Kawai ◽  
Hiroki Kato ◽  
Shintaro Sato ◽  
Ken Takahashi ◽  
...  
Keyword(s):  
Rna Viruses ◽  
Rna Virus ◽  
Critical Role ◽  
Nuclear Factor Κb ◽  
Type I ◽  
Innate Immune Responses ◽  
Antiviral Responses ◽  
Deficient Mice

IFN-β promoter stimulator (IPS)-1 was recently identified as an adapter for retinoic acid–inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (Mda5), which recognize distinct RNA viruses. Here we show the critical role of IPS-1 in antiviral responses in vivo. IPS-1–deficient mice showed severe defects in both RIG-I– and Mda5-mediated induction of type I interferon and inflammatory cytokines and were susceptible to RNA virus infection. RNA virus–induced interferon regulatory factor-3 and nuclear factor κB activation was also impaired in IPS-1–deficient cells. IPS-1, however, was not essential for the responses to either DNA virus or double-stranded B-DNA. Thus, IPS-1 is the sole adapter in both RIG-I and Mda5 signaling that mediates effective responses against a variety of RNA viruses.

scholarly journals Prognostic value of the ubiquitin ligase carboxyl terminus of the Hsc70‐interacting protein in postmenopausal breast cancer

2016 ◽  
Vol 5 (8) ◽  
pp. 1873-1882 ◽  
Author(s):  
Sasagu Kurozumi ◽  
Yuri Yamaguchi ◽  
Shin‐ichi Hayashi ◽  
Hiromi Hiyoshi ◽  
Tetsuji Suda ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Ubiquitin Ligase ◽  
Prognostic Value ◽  
Postmenopausal Breast Cancer ◽  
Carboxyl Terminus ◽  
Interacting Protein
Sign in / Sign up

Export Citation Format

Share Document