Membrane repair against H. pylori promotes cancer cell proliferation

Membrane repair is a universal response against physical and biological insults and enables cell survival. Helicobacter pylori is one of the most common human pathogens and the first formally recognized bacterial carcinogen associated with gastric cancer. However, little is known about host membrane repair in the context of H. pylori infection. Here we show that H. pylori disrupts the host plasma membrane and induces Ca2+ influx, which triggers the translocation of annexin family members A1 and A4 to the plasma membrane. This in turn activates a membrane repair response through the recruitment of lysosomal membranes and the induction of downstream signaling transduction pathways that promote cell survival and proliferation. Based on our data, we propose a new model by which H. pylori infection activates annexin A1 and A4 for membrane repair and how annexin A4 over-expression induced signaling promotes cell proliferation. Continual activation of this membrane repair response signaling cascade may cause abnormal cellular states leading to carcinogenesis. This study links H. pylori infection to membrane repair, providing insight into potential mechanisms of carcinogenesis resulting from membrane damage

Molecular mechanism of ethylene stimulation of latex yield in rubber tree (Hevea brasiliensis) revealed by de novo sequencing and transcriptome analysis

Differential expression of unigenes involved in hormone signaling in E8 and E24 compared to C samples of Hevea brasiliensis. Ethylene signalling pathway: ETR1: ETHYLENE RESPONSE 1; CTR1: CONSTITUTIVE TRIPLE RESPONSE 1; EIN2: ETHYLENE INSENSITIVE 2; EIN3: ETHYLENE INSENSITIVE 3; ERF1/2: ETHYLENE RESPONSE FACTOR 1/2; EBF1/2: EIN3 binding F-Box protein 1/2; BR signaling pathway: BRI1: Brassinosteroid-Insensitive 1; BAK1: BRI1-associated kinase 1; BKI1: BRI1 KINASE INHIBITOR 1; BSK: BR SIGNALING KINASE; BSU1: bri1 SUPPRESSOR 1; BIN2: BRASSINOSTEROID-INSENSITIVE 2; BZR1/2: BRASSINAZOLE RESISTANT 1/2; TCH: TOUCH genes; CYCD3: CYCLIN D3; GA signaling pathway: GID1: GIBBERELLIN INSENSITIVE DWARF 1; GID2: GIBBERELLIN INSENSITIVE DWARF 2; DELLAs: DELLA growth inhibitors; TF: transcriptional factor; Auxin signaling pathway: AUX1: AUXIN1; TIR1: TRANSPORT INHIBITOR RESPONSE 1; IAA: INDOLE ACETIC ACID; ARF: AUXIN RESPONSE FACTOR; SAUR: Small Auxin-Up RNA; G10H: geraniol 10-hydroxylase gene; Cytokinin signaling pathway: CRE1: CYTOKININ RESPONSE 1; AHP: histidine phosphotransfer protein; B-ARR: type-B response regulator (ARR); A-ARR: type-A response regulator (ARR); SA signalling pathway: NPR1: Non-expressor of pathogenesis-related genes 1; TGA: the bZIP transcription factors; PR1: pathogenesis related protein 1; JA signaling pathway: JAR1: JASMONATES RESISTANT 1; JA-Ile: jasmonoyl isoleucine; JAZ: Jasmonate ZIM-domain-containing protein; MYC2: a basic helix-loop-helix (bHLH) transcription factor; ORCA3: Octadecanoid-derivative Responsive Catharanthus AP2-domain gene; ABA signalling pathway: PYR1/PYLs: Pyrabactin Resistance Protein1/PYR-Like proteins; PP2Cs: protein phosphatases which fall under the category of type 2C; SnRK2: SNF1 (Sucrose-Nonfermenting Kinase1)-related protein kinase 2: ABF: ABA responsive element (ABRE) binding factors. Cells with gray border lines in the upper rows represent differentially expressed unigenes in E8 compared to C and cells with green border lines in the lower rows represent differentially expressed unigenes in E24 compared to C. Relative levels of expression are showed by a color gradient from low (blue) to high (red). (JPG 249 kb

Power-Law Decay of Standing Waves on the Surface of Topological Insulators

We propose a general theory on the standing waves (quasiparticle interference pattern) caused by the scattering of surface states off step edges in topological insulators, in which the extremal points on the constant energy contour of surface band play the dominant role. Experimentally we image the interference patterns on both Bi$_2$Te$_3$ and Bi$_2$Se$_3$ films by measuring the local density of states using a scanning tunneling microscope. The observed decay indices of the standing waves agree excellently with the theoretical prediction: In Bi$_2$Se$_3$, only a single decay index of -3/2 exists; while in Bi$_2$Te$_3$ with strongly warped surface band, it varies from -3/2 to -1/2 and finally to -1 as the energy increases. The -1/2 decay indicates that the suppression of backscattering due to time-reversal symmetry does not necessarily lead to a spatial decay rate faster than that in the conventional two-dimensional electron system. Our formalism can also explain the characteristic scattering wave vectors of the standing wave caused by non-magnetic impurities on Bi$_2$Te$_3$.Comment: 4 pages, 3 figure

1,2-Bis(p-tolyl­sulfon­yl)hydrazine

In the title compound, C14H16N2O4S2, the dihedral angle between the aromatic ring planes is 76.8 (3)° and the S—N—N—S torsion angle is 122.5 (3)°. In the crystal structure, mol­ecules form a chain structure by way of N—H⋯O hydrogen bonds

Alternative O-GlcNAcylation/O-Phosphorylation of Ser16 Induce Different Conformational Disturbances to the N Terminus of Murine Estrogen Receptor β

SummarySerine and threonine residues in many proteins can be modified by either phosphorylation or GlcNAcylation. To investigate the mechanism of O-GlcNAc and O-phosphate's reciprocal roles in modulating the degradation and activity of murine estrogen receptor β (mER-β), the conformational changes induced by O-GlcNAcylation and O-phosphorylation of Ser16 in 17-mer model peptides corresponding to the N-terminal intrinsically disordered (ID) region of mER-β were studied by NMR techniques, circular dichroism (CD), and molecular dynamics simulations. Our results suggest that O-phosphorylation discourages the turn formation in the S15STG18 fragment. In contrast, O-GlcNAcylation promotes turn formation in this region. Thus, we postulate that the different changes of the local structure in the N-terminal S15STG18 fragment of mER-β caused by O-phosphate or O-GlcNAc modification might lead to the disturbances to the dynamic ensembles of the ID region of mER-β, which is related to its modulatory activity

Association between Virulence Factors and TRAF1/4-1BB/Bcl-xL

Objective. CagA+/vacAs1+/vacAm1+ Helicobacter pylori upregulates the expression of tumor necrosis factor receptor–associated factor 1 (TRAF1), tumor necrosis factor receptor superfamily member 9 (4-1BB), and B-cell lymphoma-extra large (Bcl-xL) in human gastric epithelial cells. We investigated the correlation between cagA/vacAs1/vacAm1 and TRAF1/4-1BB/Bcl-xL expression in gastric mucosal tissue of patients with gastric disorders. Methods. We collected gastric mucosa samples from 35 chronic, nonatrophic gastritis (CG) patients, 41 atrophic gastritis patients, 44 intestinal metaplasia with atypical hyperplasia (IM) patients, and 28 gastric carcinoma (Ca) patients. The expression of  TRAF1, 4-1BB, and Bcl-xL was determined using western blotting. The expression of cagA, vacAs1, and vacAm1 in H. pylori was examined with polymerase chain reaction. Results. The expression of TRAF1, 4-1BB, and Bcl-xL was significantly upregulated in IM and Ca patients (P<0.05 compared with CG). There were more cases of cagA+/vacAs1+/vacAm1+ H. pylori infection in samples with elevated TRAF1, 4-1BB, or Bcl-xL expression (P<0.05). Additionally, there were a remarkably large number of samples with upregulated TRAF1/4-1BB/Bcl-xL expression in cases of cagA+/vacAs1+/vacAm1+ H. pylori infection (44 cases, 67.7%; P<0.05). Conclusions. The pathogenesis of IM and Ca may be promoted by cagA+/vacAs1+/vacAm1+ H. pylori, possibly via upregulated TRAF1, 4-1BB, and Bcl-xL in gastric mucosal tissue