OBJECTIVE: To investigate the effect of silencing CD46 and desmoglein 2 (DSG2) in host A549 cells on the entry of human adenovirus type 3 (HAdV-3) and type 7 (HAdV-7) and host cell secretion of inflammatory cytokines. METHODS: RNA interference technique was use to silence the expression of CD46 or DSG2 in human epithelial alveolar A549 cells as the host cells of HAdV-3 or HAdV-7. The binding of the viruses with CD46 and DSG2 were observed with immunofluorescence staining at 0.5 and 1 h after viral infection. The viral load in the host cells was determined with qRT-PCR, and IL-8 secretion level was measured using ELISA. RESULTS: In infected A549 cells, immunofluorescent staining revealed colocalization of HAdV-3 and HAdV-37 with their receptors CD46 and DSG2 at 0.5 h and 2 h after infection, and the copy number of the viruses increased progressively after the infection in a time-dependent manner. In A549 cells with CD46 silencing, the virus titers were significantly lower at 2, 6, 12 and 24 h postinfection in comparison with the cells without gene silencing; the virus titers were also significantly decreased in the cells with DSG2 silencing. The secretion level of IL-8 increased significantly in A549 cells without siRNA transfection following infection with HAdV-3 and HAdV-7 (P < 0.0001), but decreased significantly in cells with CD46 and DSG2 silencing (P < 0.0001). CONCLUSION HAdV-3 and HAdV-7 enter host cells by binding to their receptors CD46 and DSG2, and virus titer and cytokines release increase with infection time. Silencing CD46 and DSG2 can inhibit virus entry and cytokine IL-8 production in host cells.
A549 Cells ; Adenoviruses, Human/metabolism* ; Desmoglein 2/metabolism* ; Humans ; Interleukin-8 ; Membrane Cofactor Protein/genetics* ; RNA, Small Interfering

The intercalated disc (ICD) complex of cardiomyocyte consists of fascia adherens, desmosomes and gap junctions which are mainly constructed by their transmembrane proteins: N-cadherin (N-cad), desmoglein-2 (DSG2) and connexin 43 (Cx43), respectively. The aim of this study was to observe the dynamic changes in colocalization of N-cad, DSG2 and Cx43 with each other in the rat left ventricular myocardium at 1, 7, 14, 28 and 90 day(s) after birth (P1, P7, P14, P28 and P90) using immunofluorescent staining. The results showed that, N-cad, DSG2 and Cx43 located all around the plasma membrane at the P1. These proteins accumulated to the long ends of cardiomyocytes, indicating preliminary formation of the ICD at the P7. The localization of three proteins at the ICD increased progressively, but their lateral localization showed an inverse trend from the P14 to P90. However, Cx43 still kept a certain amount of lateral localization in cardiomyocytes even at the P90 as compared with N-cad and DSG2. Quantitative colocalization of proteins was analyzed by the stereological method. Total percentage of colocalization of N-cad with DSG2 was 33.5% at the P1, and increased to 38.6% at the P7, 9.4% in ICD and 29.2% in lateral side. The total percentage of colocalization of N-cad with DSG2 increased to 65.7% at the P90, ICD colocalization increasing to 60.5% and lateral colocalization decreasing to 5.2%. Total percentage of colocalization of N-cad with Cx43 increased from 10.3% at the P1 to 37.1% at the P90, and only ICD colocalization increased, but lateral colocalization kept about 5%. The colocalization pattern of DSG2 with Cx43 was similar to that of N-cad with Cx43. Total percentage of colocalization of N-cad with DSG2 was higher than those of N-cad or DSG2 with Cx43. The above results suggest that the formation of mechanical junctions at the ICD of cardiomyocyte is prior to that of electrochemistry junctions during postnatal development. In other words, cardiomyocyte growth needs a stable mechanical environment at first.
Adherens Junctions ; metabolism ; Animals ; Cadherins ; metabolism ; Cell Membrane ; metabolism ; Connexin 43 ; metabolism ; Desmoglein 2 ; metabolism ; Desmosomes ; metabolism ; Gap Junctions ; metabolism ; Heart ; growth & development ; Heart Ventricles ; metabolism ; Myocytes, Cardiac ; metabolism ; Rats

BACKGROUNDArrhythmogenic right ventricular cardiomyopathy (ARVC) is a heritable cardiac disease predominantly caused by mutations in desmosomal protein genes. Previous genetic analyses of the Chinese ARVC population are limited to small size and restriction to a single gene. This study was aimed to investigate the genotype in a large series of Chinese patients with ARVC through comprehensively screening nine ARVC-causing genes.

METHODSA total of 100 unrelated ARVC patients and 300 age, gender and ethnicity matched healthy controls were genetically tested with multiplexing targeted resequencing for nine previously reported ARVC-causing genes, including plakophilin-2, desmoplakin, desmoglein-2, desmocollin-2, plakoglobin, transforming growth factor beta-3, transmembrane protein 43, desmin and Lamin A/C.

RESULTSFifty-nine mutations were identified in 64% of the patients, among which, 93% were located in desmosomal protein genes. Plakophilin-2 mutations accounted for 54% of the total and 58% of the desmosomal mutations, with a truncating mutation type making up about 2/3 of the plakophilin-2 mutations. Only four mutations were found in non-desmosomal genes; two in transmembrane protein 43 and two in transforming growth factor beta-3. Two of them (one of each gene) appeared as single missense mutations. No mutation was identified in desmin or Lamin A/C. Multiple mutations were found in 23% of the patients, with plakophilin-2 being found in 57% of the multi-mutation carriers.

CONCLUSIONSPlakophilin-2 was the most common gene mutation that was identified in Chinese ARVC patients. Non-desmosomal genes should be added to desmosomal protein genes when performing molecular genetic screening in patients with suspected ARVC.

Adult ; Arrhythmogenic Right Ventricular Dysplasia ; genetics ; metabolism ; Asian Continental Ancestry Group ; Desmin ; genetics ; Desmoglein 2 ; genetics ; Female ; Humans ; Male ; Middle Aged ; Mutation ; Plakophilins ; genetics ; Young Adult ; gamma Catenin ; genetics

OBJECTIVE: To examine the effect of HPV-16 E6 expression on the transcription of cellular genes, we used cDNA microarray in HPV-16 E6 transfected stable cancer cell lines. METHODS: Using cDNA microarray consisting of 1,024 genes, we have performed a systematic characterization of gene expression in A549E6 human lung adenocarcinoma and RC10.1 human colon adenocarcinoma cell lines stably expressing HPV-16 E6 gene. The up-regulated and down-regulated genes were classified into the different functional categories; oncogenes, apoptosis, cell cycle, signal transduction, gene regulation, immune response, cell adhesion, protein transport, metabolism, redox control and angiogenesis. RESULTS: Among 1,024 known genes and ESTs (expressed sequence tags) tested, we found 27 up- regulated and 43 down-regulated genes in A549E6 (HPV-16 E6) compared to A549. The major up-regulated genes were as follows. GTPase-activating protein Rho 4, transcription factor D2, IKAROS, integrin-alpha 6, cadherin 11, ephrin-beta 2, RAN binding protein 2, branched-chain amino transferase 2. The major down-regulated genes were as follows. K-ras 2, CDC (cell division cycle) 37, CDC16, CDC7L1, IRF3, interferon-gamma-inducible protein 30, cadherin 6, desmoglein 1, desmocollin 2, endothelin 2. Also, we found 48 up-regulated and 34 down-regulated genes in RC10.1 (HPV-16 E6) compared to RKO. The major up-regulated genes were as follows. Colon cancer familial nonpolyposis type 1 (COCA 1), Bcl 2, jagged 1, MAP2K6, E2F1, ephrin receptor-beta 2, ephrin-beta 2, desmoglein 1, transforming growth factor-beta 3. The major down-regulated genes were as follows. KIT, Rad51C, Bcl 2 antagonist killer 1, STAT 4, epidermal growth factor receptor, high mobility group protein 2, cadherin 11, cadherin 12, cadherin 3, integrin-alpha 1, intergrin-alpha 8, chromosome segregation 1-like. CONCLUSION: Various expression patterns of cellular genes by HPV-16 E6 could be wholy grasped and classified into different functional groups using both cell line system stably expressed HPV-16 E6 and cDNA microarray analysis. These analysis methods must be helpful to understand multiple effects of a specific gene on cellular genes in a short period.
Adenocarcinoma ; Apoptosis ; Cadherins ; Carrier Proteins ; Cell Adhesion ; Cell Cycle ; Cell Line ; Centers for Disease Control and Prevention (U.S.) ; Chromosome Segregation ; Colon ; Colonic Neoplasms ; Desmoglein 1 ; DNA, Complementary* ; Endothelin-2 ; Expressed Sequence Tags ; Gene Expression* ; GTPase-Activating Proteins ; Hand Strength ; Human papillomavirus 16* ; Humans ; Lung ; Metabolism ; Oligonucleotide Array Sequence Analysis* ; Oncogenes ; Oxidation-Reduction ; Protein Transport ; Receptor, Epidermal Growth Factor ; Signal Transduction ; Transcription Factors ; Transferases