Read by QxMD icon Read


Chao Shi, Bei-Qing Pan, Feng Shi, Zhi-Hui Xie, Yan-Yi Jiang, Li Shang, Yu Zhang, Xin Xu, Yan Cai, Jia-Jie Hao, Ming-Rong Wang
Esophageal squamous cell carcinoma (ESCC) is one of the malignancies in digestive system, with a low 5-year survival rate. We previously revealed that Sequestosome 1 (SQSTM1/p62) protein levels were upregulated in ESCC tissues. However, it is unclear about the function of p62 and the underlying mechanism. Here, we used immunofluorescence and immunohistochemistry to investigate the expression of p62 in ESCC. Western blotting, quantitative RT-PCR, colony formation assay, flow cytometry, immunoprecipitation and xenograft tumor assay were used to analyze the role of p62 in vitro and vivo...
March 19, 2018: Oncogene
Meenakshi Ravichandran, Steffen Priebe, Giovanna Grigolon, Leonid Rozanov, Marco Groth, Beate Laube, Reinhard Guthke, Matthias Platzer, Kim Zarse, Michael Ristow
Whether and how regulation of genes and pathways contributes to physiological aging is topic of intense scientific debate. By performing an RNA expression-based screen for genes downregulated during aging of three different species, we identified glycine-C-acetyltransferase (GCAT, EC Impairing gcat expression promotes the lifespan of C. elegans by interfering with threonine catabolism to promote methylglyoxal (MGO; CAS 78-98-8) formation in an amine oxidase-dependent manner. MGO is a reactive dicarbonyl inducing diabetic complications in mammals by causing oxidative stress and damaging cellular components, including proteins...
March 3, 2018: Cell Metabolism
Qin Chen, Rong Deng, Xian Zhao, Haihua Yuan, Hailong Zhang, Jinzhuo Dou, Ran Chen, Hui Jin, Yanli Wang, Jian Huang, Jianxiu Yu
BACKGROUND/AIMS: An increasing number of studies have linked <unterline>e</unterline>rythropoietin-<unterline>p</unterline>roducing <unterline>h</unterline>epatocellular carcinoma (Eph) family receptor tyrosine kinases to cancer progression. However, little knowledge is available about the regulation of their functions in cancer. METHODS: SUMOylation was analyzed by performing Ni2+-NTA pull-down assay and immunoprecipitation. Cell proliferation, anchorage-independent growth, and tumorigenesis in vivo were examined by cell counting kit-8, soft agar colony formation assay, and a xenograft tumor mouse model, respectively...
March 13, 2018: Cellular Physiology and Biochemistry
Huichen Li, Ye Liang, Xiaofeng Lai, Weidong Wang, Jiang Zhang, Suning Chen
Fbw7 is a type of E3 ubiquitin ligase that targets various proteins for degradation and has been found to have a high expression level in progenitor cells. Deletion of Fbw7 in the intestine results in the accumulation of progenitor cells. Moreover, Fbw7 loss increases the susceptibility of colorectal cancer. However, the involvement of Fbw7 in the progress and development of inflammatory bowel disease (IBD) is still controversial. To identify the function of Fbw7 on dextran sodium sulfate (DSS)-induced colonic inflammation, we generated Fbw7ΔG mice, lacking Fbw7 specifically in intestinal epithelium...
March 16, 2018: Biochemical and Biophysical Research Communications
Hironao Nakayama, Tomohisa Sakaue, Masashi Maekawa, Ayako Fujisaki, Shigeki Higashiyama
A disintegrin and metalloproteinase (ADAM) family are crucial enzymes for ectodomain shedding of multiple substrates and are involved in diverse biologic and pathologic processes. However, the molecular mechanism underlying substrate selectivity of ADAMs is poorly understood. In this study, we observed that disruption of actin polymerization by pharmacological inhibitors, latrunculin A (LatA) and cytochalasin D (CyD), induced ectodomain shedding of epidermal growth factor (EGF) family ligands. Induced shedding activity by LatA or CyD was suppressed by a metalloprotease inhibitor KB-R7785, indicating that ADAMs-mediated shedding is tightly controlled by actin cytoskeleton...
March 14, 2018: Biochemical and Biophysical Research Communications
Chris Chin Wah Chen, Avigail T Erlich, David A Hood
BACKGROUND: Parkin is a ubiquitin ligase that is involved in the selective removal of dysfunctional mitochondria. This process is termed mitophagy and can assist in mitochondrial quality control. Endurance training can produce adaptations in skeletal muscle toward a more oxidative phenotype, an outcome of enhanced mitochondrial biogenesis. It remains unknown whether Parkin-mediated mitophagy is involved in training-induced increases in mitochondrial content and function. Our purpose was to determine a role for Parkin in maintaining mitochondrial turnover in muscle, and its requirement in mediating mitochondrial biogenesis following endurance exercise training...
March 17, 2018: Skeletal Muscle
Karolin Eifler, Sabine A G Cuijpers, Edwin Willemstein, Jonne A Raaijmakers, Dris El Atmioui, Huib Ovaa, René H Medema, Alfred C O Vertegaal
Signal transduction by small ubiquitin-like modifier (SUMO) regulates a myriad of nuclear processes. Here we report on the role of SUMO in mitosis in human cell lines. Knocking down the SUMO conjugation machinery results in a delay in mitosis and defects in mitotic chromosome separation. Searching for relevant SUMOylated proteins in mitosis, we identify the anaphase-promoting complex/cyclosome (APC/C), a master regulator of metaphase to anaphase transition. The APC4 subunit is the major SUMO target in the complex, containing SUMO acceptor lysines at positions 772 and 798...
March 16, 2018: Nature Communications
Chen Katz, Ana Maria Low-Calle, Joshua Choe, Oleg Laptenko, David Tong, Jazmine-Saskya N Joseph-Chowdhury, Francesca Garofalo, Yan Zhu, Assaf Friedler, Carol Prives
The p53 tumor suppressor protein is the most well studied as a regulator of transcription in the nucleus, where it exists primarily as a tetramer. However, there are other oligomeric states of p53 that are relevant to its regulation and activities. In unstressed cells, p53 is normally held in check by MDM2 that targets p53 for transcriptional repression, proteasomal degradation, and cytoplasmic localization. Here we discovered a hydrophobic region within the MDM2 N-terminal domain that binds exclusively to the dimeric form of the p53 C-terminal domain in vitro...
March 16, 2018: Genes & Development
Cheng-Dong Ji, Yan-Xia Wang, Dong-Fang Xiang, Qiang Liu, Zhi-Hua Zhou, Feng Qian, Lang Yang, Yong Ren, Wei Cui, Sen-Lin Xu, Xi-Long Zhao, Xia Zhang, Yan Wang, Peng Zhang, Ji-Ming Wang, You-Hong Cui, Xiu-Wu Bian
Potassium ion channels are emerging as pro-malignant factors involved in cancer progression. In this study, we found that invading human gastric cancer (GC) cells express high level of inwardly rectifying potassium channel 2.1 (Kir2.1). Silencing Kir2.1 markedly reduced the invasive and metastatic capabilities as well as the epithelial-mesenchymal transition (EMT) of GC cells. The pro-malignant nature of Kir2.1 in GC cells was independent of potassium permeation but relied on its interaction with serine/threonine-protein kinase 38 (Stk38) to inhibit ubiquitination and degradation of mitogen-activated protein kinase kinase kinase 2 (MEKK2)...
March 16, 2018: Cancer Research
Hyeyoon Lee, Seong-Moon Cheong, Wonhee Han, Youngmu Koo, Saet-Byeol Jo, Gun-Sik Cho, Jae-Seong Yang, Sanguk Kim, Jin-Kwan Han
Dishevelled (Dvl/Dsh) is a key scaffold protein that propagates Wnt signaling essential for embryogenesis and homeostasis. However, whether antagonism of Wnt signaling necessary for vertebrate head formation can be achieved through regulation of Dsh protein stability is unclear. Here we show that membrane-associated RING-CH2 (March2), a RING-type E3 ubiquitin ligase, antagonizes Wnt signaling by regulating the turnover of Dsh protein via ubiquitin-mediated lysosomal degradation in prospective head region of Xenopus We further found that March2 acquires regional and functional specificities for head formation from the Dsh-interacting protein Dapper1 (Dpr1)...
March 16, 2018: Development
Yukihiro Itoh, Miki Suzuki
Ubiquitin-activating enzyme (E1), which catalyzes the activation of ubiquitin in the initial step of the ubiquitination cascade, is a potential therapeutic target in multiple myeloma and breast cancer treatment. However, only a few E1 inhibitors have been reported to date. Moreover, there has been little medicinal chemistry research on the three-dimensional structure of E1. Therefore, in the present study, we attempted to identify novel E1 inhibitors using structure-based drug design. Following the rational design, synthesis, and in vitro biological evaluation of several such compounds, we identified a reversible E1 inhibitor (4b)...
March 3, 2018: Bioorganic & Medicinal Chemistry Letters
Tales Rocha de Moura, Sina Mozaffari-Jovin, Csaba Zoltán Kibédi Szabó, Jana Schmitzová, Olexandr Dybkov, Constantin Cretu, Michael Kachala, Dmitri Svergun, Henning Urlaub, Reinhard Lührmann, Vladimir Pena
Human nineteen complex (NTC) acts as a multimeric E3 ubiquitin ligase in DNA repair and splicing. The transfer of ubiquitin is mediated by Prp19-a homotetrameric component of NTC whose elongated coiled coils serve as an assembly axis for two other proteins called SPF27 and CDC5L. We find that Prp19 is inactive on its own and have elucidated the structural basis of its autoinhibition by crystallography and mutational analysis. Formation of the NTC core by stepwise assembly of SPF27, CDC5L, and PLRG1 onto the Prp19 tetramer enables ubiquitin ligation...
March 15, 2018: Molecular Cell
Ipsita Subudhi, James Shorter
Ubiquilin 2 (UBQLN2) is an amyotrophic lateral sclerosis-linked molecular chaperone with a prion-like domain that directly engages ubiquitin to triage clients for proteasomal degradation. Dao et al. (2018) now establish that UBQLN2 forms ubiquitin-labile liquids, which may enable UBQLN2 to specifically extract ubiquitylated clients from stress granules for degradation.
March 15, 2018: Molecular Cell
Yani Zhao, Pawel Dabrowski-Tumanski, Szymon Niewieczerzal, Joanna I Sulkowska
The folding of proteins with a complex knot is still an unresolved question. Based on representative members of Ubiquitin C-terminal Hydrolases (UCHs) that contain the 52 knot in the native state, we explain how UCHs are able to unfold and refold in vitro reversibly within the structure-based model. In particular, we identify two, topologically different folding/unfolding pathways and corroborate our results with experiment, recreating the chevron plot. We show that confinement effect of chaperonin or weak crowding greatly facilitates folding, simultaneously slowing down the unfolding process of UCHs, compared with bulk conditions...
March 16, 2018: PLoS Computational Biology
Ziling Fang, Bo Cao, Jun-Ming Liao, Jun Deng, Kevin D Plummer, Peng Liao, Tao Liu, Wensheng Zhang, Kun Zhang, Li Li, David Margolin, Shelya X Zeng, Jianping Xiong, Hua Lu
Ribosomal proteins (RPs) play important roles in modulating the MDM2-p53 pathway. However, less is known about the upstream regulators of the RPs. Here we identify SPIN1 (Spindlin 1) as a novel binding partner of human RPL5/uL18 that is important for this pathway. SPIN1 ablation activates p53, suppresses cell growth, reduces clonogenic ability, and induces apoptosis of human cancer cells. Mechanistically, SPIN1 sequesters uL18 in the nucleolus, preventing it from interacting with MDM2, and thereby alleviating uL18-mediated inhibition of MDM2 ubiquitin ligase activity towards p53...
March 16, 2018: ELife
Lan Hai, Maria M Szwarc, Bin He, David M Lonard, Ramakrishna Kommagani, Francesco J DeMayo, John P Lydon
Speckle-type poz protein (SPOP) is an E3-ubiquitin ligase adaptor for turnover of a diverse number of proteins involved in key cellular processes from chromatin remodeling, transcriptional regulation to cell signaling. Genomic analysis revealed that SPOP somatic mutations are found in a subset of endometrial cancers, suggesting that these mutations act as oncogenic drivers of this gynecologic malignancy. These studies also raise the question as to the role of wild type SPOP in normal uterine function. To address this question, we generated a mouse model (Spopd/d) in which SPOP is ablated in uterine cells that express the PGR...
March 13, 2018: Biology of Reproduction
Matthew R Marcello, Marina Druzhinina, Andrew Singson
The interaction and organization of proteins in the sperm membrane are important for all aspects of sperm function. We have determined the interactions between twelve known mutationally defined and cloned sperm membrane proteins in a model system for reproduction, the nematode Caenorhabditis elegans. Identification of the interactions between sperm membrane proteins will improve our understanding of and ability to characterize defects in sperm function. To identify interacting proteins, we conducted a split-ubiquitin membrane yeast two-hybrid (MYTH) analysis of gene products identified through genetic screens that are necessary for sperm function and predicted to encode transmembrane proteins...
March 13, 2018: Biology of Reproduction
Lorenza Tulli, Francesca Cattaneo, Juliette Vinot, Cosima T Baldari, Ugo D'Oro
Toll-like receptors (TLRs) play a key role in the activation of innate immune cells, in which their engagement leads to production of cytokines and co-stimulatory molecules. TLRs signaling requires recruitment of toll/IL-1R (TIR) domain-containing adaptors, such as MyD88 and/or TRIF, and leads to activation of several transcription factors, such as NF-κB, the AP1 complex, and various members of the interferon regulatory factor (IRF) family, which in turn results in triggering of several cellular functions associated with these receptors...
2018: Frontiers in Immunology
Sheng Zhang, Chengrong Xie, Honghe Li, Kang Zhang, Jie Li, Xiaomin Wang, Zhenyu Yin
Ubiquitin-specific protease 11 (USP11) is a deubiquitinating enzyme that exerts its biological functions by regulating multiple signaling pathways such as p53, NF-κB, TGF-β, and Hippo. A large body of evidence supports a link between UPS11 and tumorigenesis. However, the clinical significance and biological function of USP11 in hepatocellular carcinoma (HCC) remains unclear. Here, USP11 expression was assessed by immunohistochemistry in a pilot series of 71 HCC clinical samples, and the association between USP11 expression and clinicopathological features and overall survival time was analyzed...
March 15, 2018: Laboratory Investigation; a Journal of Technical Methods and Pathology
Sébastien Gillotin, John D Davies, Anna Philpott
The proneural transcription factor Ascl1 is a master regulator of neurogenesis, coordinating proliferation and differentiation in the central nervous system. While its expression is well characterised, post-translational regulation is much less well understood. Here we demonstrate that a population of chromatin-bound Ascl1 can be found associated with short chains of ubiquitin while cytoplasmic Ascl1 harbours much longer ubiquitin chains. Only cytoplasmic ubiquitylation targets Ascl1 for destruction, which occurs by conjugation of ubiquitin to lysines in the basic helix-loop-helix domain of Ascl1 and requires the E3 ligase Huwe1...
March 15, 2018: Scientific Reports
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"