The host takes use of pattern recognition receptors (PRRs) to defend against pathogen invasion or cellular damage. Among microorganism-associated molecular patterns detected by host PRRs, nucleic acids derived from bacteria or viruses are tightly supervised, providing a fundamental mechanism of host defense. Pathogenic DNAs are supposed to be detected by DNA sensors that induce the activation of NFκB or TBK1-IRF3 pathway. DNA sensor cGAS is widely expressed in innate immune cells and is a key sensor of invading DNAs in several cell types. cGAS binds to DNA, followed by a conformational change that allows the synthesis of cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) from adenosine triphosphate and guanosine triphosphate. cGAMP is a strong activator of STING that can activate IRF3 and subsequent type I interferon production. Here we describe recent progresses in DNA sensors especially cGAS in the innate immune responses against pathogenic DNAs.
DNA, Bacterial ; immunology ; metabolism ; DNA, Viral ; immunology ; metabolism ; Gene Expression Regulation ; Host-Pathogen Interactions ; Humans ; Immunity, Innate ; Interferon Regulatory Factor-3 ; genetics ; immunology ; Interferon Type I ; biosynthesis ; immunology ; Membrane Proteins ; genetics ; immunology ; Models, Molecular ; NF-kappa B ; genetics ; immunology ; Nucleotides, Cyclic ; biosynthesis ; immunology ; Nucleotidyltransferases ; genetics ; immunology ; Protein Binding ; Protein-Serine-Threonine Kinases ; genetics ; immunology ; Signal Transduction

To explore the antibacterial activity and mechanism of total alkaloids and berberine from Coptidis Rhizoma on Aeromonas hydrophila, and determine the effect of total alkaloids and berberine from Coptidis Rhizoma on minimum inhibitory concentrations, permeability and fluidity of cell membrane, conformation of membrane proteins and virulence factors of A. hydrophila. The results showed that both total alkaloids and berberine from Coptidis Rhizoma had antibacterial activities on A. hydrophila, with minimum inhibitory concentrations of 62.5 and 125 mg · L(-1), respectively. Total alkaloids and berberine from Coptidis Rhizoma could increase the fluidity of membrane, change the conformation of membrane porteins and increase the permeability of bacteria membrane by 24.52% and 19.66%, respectively. Besides, total alkaloids and berberine from Coptidis Rhizoma significantly decreased the hemolysis of exotoxin and the mRNA expressions of aerA and hlyA (P < 0.05, P < 0.01), the secretion of endotoxin and the mRNA expression of LpxC (P < 0.05, P < 0.01). The results suggested that the antibacterial activity of total alkaloids and berberine from Coptidis Rhizoma on A. hydrophila may be related to the bacteria membrane injury. They inhibited the bacterial growth by increasing membrane lipid fluidity and changing conformation of membrane proteins, and reduced the secretion of virulence factors of A. hydrophila to weaken the pathogenicity.
Aeromonas hydrophila ; drug effects ; genetics ; metabolism ; Alkaloids ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Bacterial Toxins ; biosynthesis ; Berberine ; pharmacology ; Cell Membrane ; drug effects ; genetics ; metabolism ; Coptis ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; Membrane Fluidity ; drug effects ; Rhizome ; chemistry

Transforming growth factor-β (TGF-β) exerts apoptotic effects on various types of malignant cells, including liver cancer cells. However, the precise mechanisms by which TGF-β induces apoptosis remain poorly known. In the present study, we have showed that threonine 32 (Thr32) residue of FoxO3 is critical for TGF-β to induce apoptosis via Bim in hepatocarcinoma Hep3B cells. Our data demonstrated that TGF-β induced FoxO3 activation through specific de-phosphorylation at Thr32. TGF-β-activated FoxO3 cooperated with Smad2/3 to mediate Bim up-regulation and apoptosis. FoxO3 (de)phosphorylation at Thr32 was regulated by casein kinase I-ε (CKI-ε). CKI inhibition by small molecule D4476 could abrogate TGF-β-induced FoxO/Smad activation, reverse Bim up-regulation, and block the sequential apoptosis. More importantly, the deregulated levels of CKI-ε and p32FoxO3 were found in human malignant liver tissues. Taken together, our findings suggest that there might be a CKI-FoxO/Smad-Bim engine in which Thr32 of FoxO3 is pivotal for TGF-β-induced apoptosis, making it a potential therapeutic target for liver cancer treatment.
Apoptosis ; genetics ; Apoptosis Regulatory Proteins ; biosynthesis ; Bcl-2-Like Protein 11 ; Carcinoma, Hepatocellular ; genetics ; pathology ; Cell Line, Tumor ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; genetics ; Gene Expression Regulation, Neoplastic ; Humans ; Liver Neoplasms ; genetics ; pathology ; Membrane Proteins ; biosynthesis ; Proto-Oncogene Proteins ; biosynthesis ; Threonine ; genetics ; Transforming Growth Factor beta ; genetics

OBJECTIVE: To investigate the expression of EBV-encoded latent membrane protein 2A (LMP2A) and epithelial-mesenchymal transformation(EMT) associated markers (E-cadherin and fibronectin) in nasopharyngeal carcinoma (NPC) and its clinical significance. METHOD: The expression of LMP2A, E-cad-herin and fibronectin proteins in 32 cases of chronic nasopharyngeal inflammation, 56 cases of NPC and 18 cases of NPC lymph node metastasis were examined byimmunohistochemical SP method. RESULT: (1)The positive rates of LMP2A in NPC and its lymph node metastasis were significantly higher than those of chronic nasopharyngeal inflammation (89. 3%vs 37. 5%o and 77. 8% vs 37. 5%) respectively (both P<0. 01); The normal expression rates of E-cadherin in NPC and its lymph node metastasis were significantly lower than those of chronic nasopharyngeal inflammation (33. 9% vs 90. 6% and 5. 6% vs 90. 6%) respectively (both P<0. 01); The positive rates of fibronectin in NPC and its lymph node metastasis were significantly higher than those of chronic nasopharyngeal inflammation (83. 9% vs 28. 1% and 72. 2% vs 28. 1%) respectively (both P<0. 01). (2) ZLMP2A expression were negatively correlated with normal expression of E-cadherin (r= -0. 387, P<0. 01), and were positively correlated with fibronectin (r= 0. 421, P<0. 01). (3)LMP2A, E-cadherin and fibronectin expression were significantly correlated with N stage and clinical stage (both P<0. 05), but the three proteins were not significantly correlated with M stage (both P> 0. 05). In addition, LMP2A and E-cadherin expression were significantly correlated with T stage (both P<0. 01). CONCLUSION LMP2A and fibronectin expressions were increased in NPC, but normal expression of E-cadherin were decreased. LMP2A may promote lymph node metastasis and malignant progression of NPC by induce EMT through downregulation of E-cadherin and upregulation of fibronectin.
Cadherins ; biosynthesis ; Carcinoma ; Epithelial-Mesenchymal Transition ; Fibronectins ; biosynthesis ; Humans ; Lymphatic Metastasis ; Membrane Proteins ; biosynthesis ; Nasopharyngeal Carcinoma ; Nasopharyngeal Neoplasms ; metabolism ; pathology ; Nasopharynx

Mitochondrial morphology is dynamically regulated by forming small, fragmented units or interconnected networks, and this is a pivotal process that is used to maintain mitochondrial homeostasis. Although dysregulation of mitochondrial dynamics is related to the pathogenesis of several human diseases, its molecular mechanism is not fully elucidated. In this study, we demonstrate the potential role of miR-27 in the regulation of mitochondrial dynamics. Mitochondrial fission factor (MFF) mRNA is a direct target of miR-27, whose ectopic expression decreases MFF expression through binding to its 3'-untranslated region. Expression of miR-27 results in the elongation of mitochondria as well as an increased mitochondrial membrane potential and mitochondrial ATP level. Our results suggest that miR-27 is a novel regulator affecting morphological mitochondrial changes by targeting MFF.
3' Untranslated Regions ; Cell Line ; Gene Expression Regulation ; Humans ; Membrane Potential, Mitochondrial ; Membrane Proteins/*genetics ; MicroRNAs/*metabolism ; Mitochondria/*genetics/*metabolism ; *Mitochondrial Dynamics ; Mitochondrial Proteins/*genetics ; *Protein Biosynthesis ; RNA, Messenger/genetics/metabolism

This study was aimed to investigated the mRNA expression levels of Notch ligands- Delta-like-1 and Jagged-1 in bone marrow mesenchymal stem cells of patients with myelodysplastic syndrome (MDS), and to explore their relation with onset of MDS. Bone marrow mesenchymal stem cells of 38 patients with MDS and 16 normal subjects as control were collected to detect mRNA expression of Delta-like-1 and Jagged-1 by using real-time quantitative polymerase chain reaction. The results showed that the expression levels of Delta-like-1 and Jagged-1 in mesenchymal stem cells of MDS patients were significantly higher than that in normal controls (P < 0.05). According to WHO criteria, the mRNA expression of Delta-like-1 in RA/RAS, RCMD and RAEB groups were significantly higher than that in normal controls (P < 0.05), the mRNA expression of Jagged-1 in RAEB group was also significantly higher than that in normal controls (P < 0.05). The mRNA expression of Delta-like-1 was significantly correlated with the proportion of blasts in the bone marrow of MDS patients (r = 0.502, P < 0.05). The expression levels of Delta-like-1 and Jagged-1 in MDS patients with abnormal karyotypes were significantly higher than those in MDS patients with normal karyotypes (P < 0.05). The mRNA expression of Delta-like-1 in higher risk group according to International Prognostic Scoring System was significantly higher than that in lower risk group (P < 0.05), there was no significant difference in Jagged-1 expression levels between higher risk group and lower risk group (P > 0.05). It is concluded that the changes of Delta-like-1 and Jagged-1 expression level in MSC may play a role in the pathogenesis of myelodysplastic syndrome.
Calcium-Binding Proteins ; genetics ; Gene Expression Regulation, Neoplastic ; Humans ; Intercellular Signaling Peptides and Proteins ; genetics ; Intracellular Signaling Peptides and Proteins ; genetics ; Jagged-1 Protein ; Membrane Proteins ; genetics ; Mesenchymal Stromal Cells ; metabolism ; Myelodysplastic Syndromes ; genetics ; RNA, Messenger ; biosynthesis ; Serrate-Jagged Proteins

The relationship between T cell immunoglobulin domain and mucin domain protein 3 (Tim-3)/Galectin (Gal)-9 pathway and recurrent spontaneous abortion (RSA) was studied. Thirty-one pregnant women with RSA and 27 normal early gravidas were investigated to detect the levels of Tim-3 and Gal-9 in villi and deciduas by Western blotting. Meanwhile, the concentration of interleukin (IL)-4 and IL-12 in peripheral blood plasma was determined by ELISA in 25 healthy fertile non-pregnant controls, the normal early gravidas and pregnant women with RSA mentioned above, respectively. It was found that the relative expression levels of Tim-3 and Gal-9 in villi and deciduas were significantly increased in pregnant women with RSA as compared with those in the normal early gravidas. The concentration of IL-4 in peripheral blood plasma of pregnant women with RSA was lower than that of the normal early gravidas (P<0.05) and healthy fertile non-pregnant controls (P<0.05), but that of IL-2 in pregnant women with RSA was significantly higher than that of the normal early gravidas (P<0.05) and healthy fertile non-pregnant controls (P<0.05). It was suggested that the overexpression of Tim-3/Gal-9 pathway may be related to the pathogenesis of RSA.
Abortion, Spontaneous ; metabolism ; pathology ; Adolescent ; Adult ; Chorionic Villi ; metabolism ; pathology ; Female ; Galectins ; biosynthesis ; Hepatitis A Virus Cellular Receptor 2 ; Humans ; Interleukin-12 ; blood ; Interleukin-4 ; blood ; Membrane Proteins ; biosynthesis ; Pregnancy ; Pregnancy Proteins ; biosynthesis ; Up-Regulation

Autophagy dysregulation, mitochondrial dynamic abnormality and cell cycle re-entry are implicated in the vulnerable neurons of patients with Alzheimer's disease. This study was designed to testify the association among autophagy, mitochondrial dynamics and cell cycle in dividing neuroblastoma (N2a) cells. The N2a cells were cultured in vitro and treated with different concentrations of 3-methyladenine (3-MA). The cell viability was detected by methyl thiazolyl tetrazolium (MTT) assay. They were randomly divided into control group (cells cultured in normal culture medium) and 3-MA group (cells treated with 10 mmol/L 3-MA). The cell cycle was analyzed in the two groups 3, 6, 12, and 24 h after treatment by flow cytometry. Western blotting was used to evaluate the expression levels of mitofission 1 (Fis1), mitofusin 2 (Mfn2), microtubule-associated protein 1 light chain 3 (LC3), cell cycle-dependent kinase 4 (CDK4) and cdc2. The flow cytometry revealed that the proportion of cells in G(2)/M was significantly increased, and that in G0/G1 was significantly reduced in the 3-MA group as compared with the control group. Western blotting showed that the expression levels of Fis1, LC3, and CDK4 were significantly up-regulated in the 3-MA group at the four indicated time points as compared with the control group. Mfn2 was initially decreased in the 3-MA group, and then significantly increased at 6 h or 12 h. Cdc2 was significantly increased in the 3-MA group at 3 h and 6 h, and then dropped significantly at 12 h and 24 h. Our data indicated that 3-MA-induced suppressed autophagy may interfere with the cell cycle progression and mitochondrial dynamics, and cause cell death. There are interactions among cell cycle, mitochondrial dynamics and autophagy in neurons.
Adenine ; administration & dosage ; analogs & derivatives ; Apoptosis ; drug effects ; Autophagy ; drug effects ; genetics ; CDC2 Protein Kinase ; Cell Cycle ; drug effects ; genetics ; Cell Division ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Cyclin B ; biosynthesis ; Cyclin-Dependent Kinases ; Gene Expression Regulation ; drug effects ; Humans ; Membrane Proteins ; biosynthesis ; Microtubule-Associated Proteins ; biosynthesis ; Mitochondrial Dynamics ; drug effects ; genetics ; Mitochondrial Proteins ; biosynthesis ; Neuroblastoma ; Signal Transduction ; drug effects

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by abnormal proliferation of synoviocytes, leukocyte infiltration, and angiogenesis. The endoplasmic reticulum (ER) is the site of biosynthesis for all secreted and membrane proteins. The accumulation of unfolded proteins in the ER leads to a condition known as ER stress. Failure of the ER's adaptive capacity results in abnormal activation of the unfolded protein response. Recently, we have demonstrated that ER stress-associated gene signatures are highly expressed in RA synovium and synovial cells. Mice with Grp78 haploinsufficiency exhibit the suppression of experimentally induced arthritis, suggesting that the ER chaperone GRP78 is crucial for RA pathogenesis. Moreover, increasing evidence has suggested that GRP78 participates in antibody generation, T cell proliferation, and pro-inflammatory cytokine production, and is therefore one of the potential therapeutic targets for RA. In this review, we discuss the putative, pathophysiological roles of ER stress and GRP78 in RA pathogenesis.
Animals ; Arthritis, Rheumatoid/genetics/*pathology ; Autoantibodies/immunology ; Cell Proliferation ; Cytokines/biosynthesis/immunology ; Endoplasmic Reticulum/immunology/pathology ; Endoplasmic Reticulum Stress/*immunology ; Haploinsufficiency/genetics ; Heat-Shock Proteins/*genetics/*immunology ; Humans ; Lymphocyte Activation ; Mice ; Neovascularization, Pathologic/genetics ; Protein Folding ; Synovial Membrane/cytology ; T-Lymphocytes/immunology ; Unfolded Protein Response/*immunology

Secretory anti-gp96 scFv fragment was expressed in Pichia pastoris to obtain a small molecule antibody that specifically recognizes heat shock protein gp96. The gp96-scFv fragment gene was synthesized and cloned to Pichia pastoris expression plasmid pPICZa-A. Pichia pastoris X33 was electroporated with the linearized recombinant expression vector, and expression of gp96-scFv fragment was induced by methanol. The His-tagged recombinant protein was then purified by affinity chromatography and analyzed with SDS-PAGE and Western blotting assays. The biological activities of recombinant gp96-scFv fragment were determined by Western blotting, Immunofluorescence, ELISA and FACS assays. The gp96-scFv fragment was expressed successfully in Pichia pastoris. About 50 mg of recombinant protein could be purified from 1 liter of the Pichia pastoris culture supernatant. Its molecular weight was about 15 kDa. The gp96-scFv fragment could specifically bind to gp96 protein by Western blotting, immunofluorescence, ELISA and FACS analyses. Pichia pastoris-expressed gp96-scFv fragment specifically recognizes gp96 protein, which could be used for Western blotting, Immunofluorescence, ELISA and FACS analyses.
Blotting, Western ; Chromatography, Affinity ; Electrophoresis, Polyacrylamide Gel ; Enzyme-Linked Immunosorbent Assay ; Membrane Glycoproteins ; immunology ; Pichia ; metabolism ; Plasmids ; Recombinant Proteins ; biosynthesis ; Single-Chain Antibodies ; biosynthesis