Linking lignocellulosic dietary patterns with gut microbial Enterotypes of Tsaitermes ampliceps and comparison with Mironasutitermes shangchengensis.

Tsaitermes ampliceps (lower termites) and Mironasutitermes shangchengensis (higher termites) are highly eusocial insects that thrive on recalcitrant lignocellulosic diets through nutritional symbioses with gut dwelling prokaryotes and eukaryotes. We used denaturing gradient gel electrophoresis and a 16S rRNA clone library to investigate i) how microbial communities adapt to lignocellulosic diets with different cellulose and lignin content, ii) the differences in the dominant gut microbial communities of the 2 types of termites. The results indicated that gut microbiota composition in T. ampliceps was profoundly affected by 2-week diet shifts. Comparison of these changes indicated that Bacteroidetes and Spirochaetes act in cellulose degradation, while Firmicutes were responsible for lignin degradation. Additionally, Proteobacteria consistently participated in energy production and balanced the gut environment. Bacteroidetes may function without hindgut protozoans in higher termites. The diversity of enteric microorganisms in M. shangchengensis was higher than that in T. ampliceps, possibly because of the more complicated survival mechanisms of higher termites.

Three branches of phospholipase C signaling pathway promote hepatocyte growth in rat liver regeneration.

In general, the phospholipase C (PLC) signaling pathway is involved in many physiological activities, including cell growth. However, little is known regarding how the PLC signaling pathway participates in regulating hepatocyte (HC) growth during liver regeneration (LR). To further explore the influence of the PLC signaling pathway on HCs at the cellular level, HCs of high purity and vitality were isolated using Percoll density-gradient centrifugation after partial hepatectomy. The genes of the PLC signaling pathway and target genes of transcription factors in the pathway were obtained by searching the pathways and transcription factor databases, and changes in gene expression of isolated HCs were examined using the Rat Genome 230 2.0 Microarray. The results suggested that various genes involved in the pathway (including 151 known genes and 39 homologous genes) and cell growth (including 262 known genes and 37 homologous genes) were associated with LR. Subsequently, the synergetic effect of these genes in LR was analyzed using a mathematical model (Et) according to their expression profiles. The results showed that the Et values of G protein-coupled receptor/PLC, integrin/PLC, and growth factor receptor/PLC branches of the PLC pathway were all significantly strengthened during the progression and termination phases of LR. The synergetic effect of target genes, in parallel with target gene-related cell growth, was also enhanced during whole rat LR, suggesting the potential positive effect of PLC on HC growth. The present data indicate that the PLC signaling pathway may promote HC growth through 3 mechanisms during rat LR after partial hepatectomy.

Protective role of neuregulin-1 toward doxorubicin-induced myocardial toxicity.

The aim of this study was to investigate the role of the rat neuregulin-1 (NRG-1) protein in reducing doxorubicin (DOX)-induced myocardial toxicity and its underlying mechanism. The prokaryotic expression of the NRG-1 protein and the CCK8-determined activity of rat primary myocardial cells were evaluated under different DOX concentrations. Myocardial cells were divided into three groups: the control group, the 5 µM DOX (DOX5) group, and the DOX5+NRG-1 group. Western blotting was used to determine the Na+-Ca2+ exchanger (NCX-1) and cardiac myosin light-chain kinase (cMLCK) protein expression levels and real-time quantitative polymerase chain reaction methods were used to determine the mRNA expression levels. The prokaryotic expression of NRG-1 in the DOX5 group produced toxicity in the rat myocardial cells, and cell activity was significantly restored with the addition of NRG-1. The protective effect of NRG-1 was limited at higher DOX concentrations (DOX10), and the degree of cellular activity restoration was positively correlated with NRG-1 concentration. The addition of NRG-1 to DOX5 intervention inhibited NCX-1 protein and mRNA expression, and increased cMLCK protein and mRNA expression. In conclusion, DOX-induced toxicity in rat myocardial cells could be protected by NRG-1, and the mechanism may be related to the role of NRG-1 in up-regulating the cMLCK expression level and down-regulating the NCX-1 expression level.

Identification of a novel human testicular interstitial gene, RNF148, and its expression regulated by histone deacetylases.

Multiple genes are restrictively expressed in mammalian testicular tissues, and they play important roles in the complex process of spermatogenesis. Investigation of these genes and their expression regulation mechanisms is valuable to elucidate the molecular process of spermatogenesis. In this study, we identified a novel human gene, ring finger protein 148 (RNF148) that is abundantly expressed in testes and slightly expressed in pancreas. In situ hybridization analysis showed that RNF148 messenger RNA was mainly present in the interstitial cells of human testicular tissues, and immunohistochemical analysis confirmed protein levels in that location. Treatment with histone deacetylase inhibitor trichostatin A activated the expression of RNF148 messenger RNA in a time- and concentration-dependent manner in HEK293T and HeLa cells, neither of which normally express RNF148. Chromatin immunoprecipitation analysis showed that trichostatin A treatment increased the binding of acetylated histone H3 to the RNF148 gene promoter. We identified a novel human testicular interstitial gene and observed that histone deacetylases regulate RNF148 expression.

Target replacement strategy for selection of DNA aptamers against the Fc region of mouse IgG.

Aptamers that recognize the IgG Fc region are of great interest because of their wide application as an immunology probing tool, for diagnostics, and as affinity agents for antibody purification. We developed a target replacement strategy as a modification of conventional Systematic Evolution of Ligands by EXponential enrichment (SELEX) in order to efficiently select and identify novel DNA aptamers against the Fc region of mouse IgG. In this new approach, multiple IgG subclasses (IgG1, IgG2a, mouse IgG Fc, and anti-HBs IgG) were sequentially used to select aptamers in one continuous SELEX. After 8 rounds of selection, the aptamers were analyzed using dot blot and an electrophoretic mobility shift assay, which showed universal binding capability to different IgG subclasses. Secondary structure analysis of the aptamers indicated that the stem-loop structure of the aptamers play an important role in binding to the common site in different mouse IgG subclasses. This demonstrated the feasibility of using multiple target replacement SELEX for the selection of aptamers. This target replacement strategy is also expected to be useful for selecting aptamers that bind common regions of molecules other than antibodies.

Parallel proteomic analysis in muscle-invasive bladder transitional cell carcinoma and cancer-related stroma.

To bring about improvements in cancer biology research and elucidate mechanism-based therapeutic targets, we studied the proteome expression profile of purified normal urothelial cells (cancer cells) and normal stromal cells (cancerous stromal cells). Based on the expression profile, biomarker discovery and the mechanisms of multi-step carcinogenesis were explored. We found that 1412/1403 unique proteins commonly appeared in 4 sets of paired cancer/normal tissue, and 1753 proteins were differentially expressed. Three hundred and forty-one proteins were repeatedly expressed in both cancer and cancer stromal cells; 358 proteins were repeatedly expressed in both normal urothelial and normal stromal cells. Among them, 186/203 proteins were specific repeat expressions in cancer/normal tissue and thought to play an important role in cancer-stroma interactions. Differential proteins were further analyzed using bioinformatic tools and compared with the published literature. GO enrichment/depletion analysis indicated that carcinogenesis involved all the biological processes and all the cellular components. Five hundred and sixty-eight differential proteins were located in the well-known biological Kyoto Encyclopedia of Genes and Genomes pathways, including metabolic pathways, ribosome spliceosome, and endocytosis. One hundred and thirty-nine of the 186 proteins that displayed specific repeat expressions in cancer tissue were located in the biological Kyoto Encyclopedia of Genes and Genomes pathways and are thought to be candidate biomarkers for targeted therapy.

Association of killer cell immunoglobulin-like receptors with pulmonary tuberculosis in Chinese Han.

Killer cell immunoglobulin-like receptors (KIRs) are involved in the pathogenesis of a variety of diseases. However, whether KIR polymorphism is associated with susceptibility to pulmonary tuberculosis was unknown. We examined a possible association of KIR polymorphism with susceptibility to pulmonary tuberculosis in Chinese Han. We analyzed 15 KIR genes in 109 pulmonary tuberculosis patients and 110 healthy controls using sequence-specific primer PCR analysis of genomic DNA. We found that the frequencies of KIR2DS1, 2DS3 and 3DS1 were significantly higher in patients than in the control group. In addition, the number of subjects carrying more than two activating KIR genes in the patient group was significantly higher than in the control group. The gene cluster containing KIR3DS1-2DL5-2DS1-2DS5 was also significantly more frequent in the patient group. In conclusion, KIR genes 2DS1, 2DS3 and 3DS1 appear to be associated with resistance to pulmonary tuberculosis in the Chinese Han population. KIR genes apparently have a role in resistance to pulmonary tuberculosis.