Journal: Hepatology (Baltimore, Md.)
Article Title: Tumor suppressive role of the antimicrobial lectin REG3A targeting the O -GlcNAc glycosylation pathway
doi: 10.1097/HEP.0000000000000993
Figure Lengend Snippet: REG3A bound to glucose and glucose intermediates is a regulator of protein glycosylation. (A) Quantification of HS and CS disaccharides by ion-pair reversed-phase chromatography in HuH7 cells expressing REG3A or EXTL3 alone, or both, or appropriate empty vectors. (B) Representative sugar slot blot of mono- and polysaccharides deposited at the indicated doses and hybridized with recombinant REG3A lectin. Lactose, mannan: positive control for REG3A binding. (C) Slot blot of indicated sugars in the presence of a full-length human recombinant REG3A protein (rcREG3A) preincubated with BSA or BSA + lactose (Glc-Gal). (D) Slot blot of indicated sugars in the presence of rcREG3A or a mutant recombinant REG3A protein (rcREG3A EPN/GPG ) proteins. (E) Immunoblots for O -GlcNAc (anti-RL2) and REG3A in nuclear fractions of HuH7 cells expressing REG3A, REG3A EPN/GPG or empty vector. Densitometry quantification (n = 3). (F) Enzymatic quantification of cellular UDP-GlcNAc content in preneoplastic (preK), nontumor (NT adjacent to a tumor), and tumor (T) liver samples from MYC/REG3A and MYC-TG transgenic mice. Each dot represents a sample of an individual mouse. (G) Rates of cellular ATP production in HuH7 cells expressing REG3A, REG3A EPN/GPG , or the empty vector, showing significant changes in total, mitochondrial, and glycolytic ATP production under the action of the full-length REG3A protein (n = 3). (H) Lectin blot for biotin-labeled PHA-L (phaseolus vulgaris leucoagglutinin) lectin on preneoplastic liver extracts from mice transgenic for MYC (MYC-TG) and for MYC and REG3A (MYC/REG3A-TG). Densitometry quantification (n = 6). (I) Glycogen concentrations in preneoplastic liver extracts (preK; left) from the mice shown (n = 6) and (J) in HuH7 cells expressing full-length REG3A or the mutant REG3A EPN/GPG (right) (n = 4). (K) Lectin blot for biotin-labeled WGA in extracts of preneoplastic (PreK) liver from MYC and MYC/REG3A transgenic mice and quantification by densitometry (n = 6). (L) A schematic view of carbohydrate metabolism from glucose and its intermediates. Gray = de novo synthesis of UDP-GlcNAc from glucose through the hexosamine synthesis pathway; Blue: salvage of GlcNAc through the metabolic processes that produce UDP-GlcNAc. *sugars bound to REG3A. Red arrows: carbohydrate pathways downregulated by REG3A. Equal symbols: glucose pathways not modulated by REG3A. Data are averages ± SEM. The Mann-Whitney U test was used for analysis, except for (E), (F), (G), and (J) (ANOVA test followed by a post hoc test). NS or no statistical indication, no significance. Abbreviations: CS, chondroitin sulfate; EXTL3, exostosin-like glycosyltransferase 3; HS, heparan sulfate; PHA-L, phytohemaglutinin-L; REG3A, regenerating family member 3 alpha; WGA, wheat germ agglutinin.
Article Snippet: They warmly thank Patricia Duchambon and her colleagues at the Unité d’Expression et de Purification des Protéines for the production of a recombinant human REG3A protein (CNRS UMR9187, Inserm U1196, Institut Curie, Université Paris-Saclay, Orsay, France).
Techniques: Glycoproteomics, Reversed-phase Chromatography, Expressing, Dot Blot, Recombinant, Positive Control, Binding Assay, Mutagenesis, Western Blot, Plasmid Preparation, Transgenic Assay, Labeling, MANN-WHITNEY