Abstract:STING (stimulator of interferon genes) is a novel regulatory protein in innate immune signaling pathways, which has been shown to be essential for the production of type Ⅰ interferon in response to certain viruses and intracellular bacteria. B type dsDNA and 5′-3p dsRNA are detected by the corresponding pattern recognition receptors (PRRs) after exposing to host cells, which pass signals to STING. STING then recruits TBK1 to activate IRF3 and induce IFN by the similar mechanism. Besides, STING can be a PRR of the cyclic dinucleotides, such as c-di-GMP and c-di-AMP in bacteria, to induce type Ⅰ interferon response. Except IFN, STING also activates STAT6 to induce some specific chemokines capable of attracting various immune cells. Here, we review recent studies on STING's structure, location, function, and regulatory mechanisms in the innate immune pathway, which provide an important theoretical guidance for the development of new antiviral immunotherapy.

Abstract:Interoception is the sense of the physiological condition of the body. Recent studies suggested that interoception is involved in drug addiction and insular cortex is a key anatomical position. The neural mechanisms underlying such phenomena attract growing attention. In an effort to develop working hypotheses for future investigation, the article first reviewed the evidence of interoceptive regulation of addiction, and subsequently presented human and animal data that suggest a central role of the insular cortex in mediating interoception and addiction. On this basis, we proposed potential neurobiological mechanisms through which insular cortex may mediate drug addiction. Further, possible functional roles of neurotransmitters in the insular cortex are discussed in the context of drug addiction.

Abstract:Production of mature mRNA consists of a highly complex pathway of synthesis, and errors often happen. Both prokaryotic and eukaryotic cells have evolved remarkable surveillance mechanisms acting at several steps of mRNA biogenesis, even after translation initiation, to control mRNA quality. In eukaryotic cells, there are 4 translation-dependent mRNA surveillance pathways in cytoplasm, including nonsense-mediated decay(NMD), no-go decay (NGD), non-stop decay (NSD) and ribosome extension-mediated decay(REMD). These mRNA surveillance systems not only contribute to recognize and rapidly degrades aberrant mRNAs, but also play an essential role in gene regulation, and associated with several human diseases. In this review, recent achievements in the investigation of eukaryotic mRNA surveillance pathways will be discussed, and their application perspective will also be speculated.

Abstract:So far, systematic analysis of protein translation process is still far behind that of transcriptome. The ribosome profiling, based on deep sequencing of the ribosome-protected mRNA fragments, makes it possible to deeply and precisely study genome-wide protein translation process and translation regulation. This review introduces the development, construction and analysis of the ribosome profiling, and focuses on its wide applications. These applications include discovering novel ORFs (such as uORF and sORF), deciphering the mechanism of microRNA functional roles, charactering the translation efficiency and differential translation, predicting the protein abundance and illustrating the mechanism of protein translation. Finally, we analyze the broad development prospect of ribosome profiling.

Abstract:Ruiz-Lozano reported that APJ is a bifunctional receptor for both mechanical stretch and the endogenous peptide apelin and play a different role in cardiomyocyte hypertrophy. The paper “APJ acts as a dual receptor in cardiac hypertrophy” is reported in the nature journal (nature,488:394-398, 16 July 2012) . It is reported that APJ is a bifunctional receptor for both mechanical stretch and the endogenous peptide apelin in cardiomyocyte hypertrophy. Activation of APJ by stretch is a G-protein-independent way to induce hypertrophy; while apelin stimulates APJ to activate Gai and elicits a protective response. By sensing the balance between these stimulates, APJ occupies a pivotal point linking sustained overload to cardiomyocyte hypertrophy. This is a significant breakthrough for apelin/APJ system and it provided a new direction of APJ regulation, and it also provides a new treatment of myocardial hypertrophy.

Abstract:The bacterial phage ΦBT1 integrase is a promising tool due to its site-specific transgene character. It enriches the site-specific transgenic tools and provides the possibility for multiple site-specific transgenic manipulations. To improve its safety as a vector of gene therapy, it is necessary to investigate the potential interactions between ΦBT1 and proteins in mammalian host cells. Yeast mating and co-immunoprecipitation assay indicated that a tetrapeptide 433RFAL436 in ΦBT1 integrase was responsible for ΦBT1 and Daxx interaction. It was also demonstrated that over-expression of Daxx could reduce ΦBT1 mediated recombination rate in 293T cells by using ΦBT1 report system. It is the first time to identify a cellular protein interacting with ΦBT1 integrase and inhibiting its recombination efficiency. This result might be useful for improving the ΦBT1 integrase mediated transgene methods and directing the selection of target cells for ΦBT1 integrase.

Abstract:In recent years, OCT-4 and AP-2γ have been widely used as clinical markers of testicular germ cell tumors. Transcription factor OCT-4, which plays an important role in embryonic development, gives full play to a variety of biological functions in different developmental periods and differentiations. The effect of OCT-4 is realized through the regulation of the target genes. In this study, we found OCT-4 binding sites within the sequence of AP-2γ promoter region by a variety of bionemerics. AP-2γ, a novel target gene of OCT-4, was identified by chromatin immunoprecipitation (ChIP) -PCR. A combination of sequence analysis, reporter gene assays, Western blot, immunofluorescence assay and mouse cryptorchidism model experiment further confirmed that AP-2γ was the target gene of OCT-4. OCT-4 inhibited the transcriptive activity of AP-2γ. The expression of AP-2γ gene was confirmed to be significantly altered by silencing or overexpression of OCT-4. This new discovery is conductive to study the malignant process of germ cell tumors at the molecular level.

Abstract:We examined the effect of myricetin on cell dysfunction in cytokine-induced pancreatic β cells and assessed whether Wnt signal pathway was the target of myricetin. RIN-m5f β cells were exposed to a combination of tumor necrosis factor-α, interleukin-1β, and interferon-γ, with or without myricetin pretreatment for 48 h. The cell viability, basal and glucose-stimulated insulin secretion and Wnt-signaling proteins were evaluated with methyl thiazolyl tetrazolium assay, radio immunoassay and Western blotting, respectively. The 48 h multiple-cytokine treatment decreased cell viability and glucose-stimulated insulin secretion, while increasing basal insulin secretion. Western blot analysis showed that Wnt-signaling proteins were decreased in cytokine-treated RIN-m5f cells. However, myricetin pretreatment protected against cytokine-induced cell death. In addition, myricetin (20 μmol/L) obviously decreased basal insulin secretion and increased glucose-stimulated insulin secretion in cytokine-treated RIN-m5f cells. Western blot analysis showed that Wnt-signaling proteins were increased after myricetin pretreatment. Therefore, myricetin might attenuate cell dysfunction in cytokine-induced RIN-m5F cells via the Wnt signal pathway, and the Wnt signal pathway might be used as a new target for protecting pancreatic β cells against cytokine-induced cell dysfunction and death.

Abstract:To investigate the effects of lentivirus on the growth and development of porcine fetal fibroblasts (PFBs), in this study PFBs were repeatedly infected by lentivirus. The results showed that lentivirus-mediated enhanced green fluorescent protein (EGFP) had stable and efficient expression in PFBs. Under the condition with leukemia inhibitory factor (LIF) and basic fibroblast growth factor (bFGF), some PFBs gradually changed their fibrous growth pattern into round cell morphology. These round cells proliferated and formed cell clones with clear edge boundary. Clones grew rapidly on feeder layers and passaged stably with normal karyotypes. These cells were positive for alkaline phosphatase (AP) and expressed stem cell markers Oct4, Nanog, and SSEA1. In addition, these cells formed embryoid bodies (EB) in vitro and three germ layers in vivo. After the cells were used as nuclear donors, the cleavage rate of the cloned embryos was 53.33%, the morula rate 9.03%, the blastocyst rate 2.07%, and the total cell number per hatched blastocyst was 26.5. Compared with embryos cloned from non- lentivirus PFBs, the morula rate and blastocyst rate were lower and significantly different (P < 0.05). Lentivirus can result in the generation of porcine iPS cells from PFBs, so it can be used as ideal material and tool for research such as epigenetic modification and cell reprogramming.

Abstract:Many studies have demonstrated that ZNF185, a LIM domain protein, acts as a tumor suppressor in several types of tumor cell. However, the role of ZNF185 in leukemia cells remains unclear, though it is highly expressed in the cells of human blood system. In the present study, we found dramatically decreased ZNF185 expression in the acute and chronic myeloid leukemia cell line HL-60 and K562 compared with that in normal neutrophils. To explore the role of ZNF185 in the proliferation of myeloid leukemia cells, complete coding sequence of ZNF185 was cloned and transfected into K562 cells, MTT assay showed that over expression of ZNF185 in K562 cells significantly inhibited its proliferation. To explore the molecular mechanism that regulates ZNF185 expression in myeloid leukemia cells, methylation specific PCR (MSP) was performed to determine the methylation status of ZNF185 promoter in the normal PBL neutrophils, HL-60 and K562 cells. Higher methylation of ZNF185 promoter was detected in HL-60 and K562 cells than that in normal PBL neutrophils. Furthermore, treatment of K562 cells with 5-aza-CdR, a DNA demethylation agent, resulted in demethylation of ZNF185 promoter, increased ZNF185 expression and inhibited K562 cell proliferation. Our results indicate that ZNF185 promoter methylation which reduces ZNF185 expression in K562 cells and its ability to inhibit cell proliferation may be one of the molecular mechanisms that are related to the occurrence or development of chromic myeloid leukemia.

Abstract:In order to improve the cloning efficiency and obtain human lysozyme (hLY) gene transgenic pigs, the present study was carried out to investigate the effects of different electric activation parameters and chemicals on in vitro development of embryos derived from parthenogenesis (PA) and somatic cell nuclear transfer (SCNT). The results showed that the electric strength could influence the fusion rate and developmental ability of SCNT embryos (P < 0.05), and number of electric pulses had no significant effect on SCNT embryos development (P > 0.05), yet different variation tendency was found in developmental ability between PA and SCNT embryos under same activation parameters. The blastocyst rate of SCNT embryos was improved when treated with CHX CB for 4 h after electric activation (P < 0.05), whereas 6-DMAP did not (P > 0.05). On the contrary, either CHX CB or 6-DMAP treatment after electric pulses could improve the blastocyst rate of PA embryos, indicating that the best activation method for PA was not necessarily the best for SCNT. The best activation protocol of SCNT embryos in our study is two pulses of 100 μs, direct current of 1.6 kV/cm electric strength with 100 μs interval, and followed by CHX CB treatment for 4 h. With the activation protocol, the mammary gland expressed hLY transgenic pigs were generated. It could help for improving piglets survival rate in transgenic breeding.

Abstract:One basic research for proteomics is protein identification. For large-scale protein identification, shotgun techniques are usually applied, i.e., some digested peptides (precursor ions) are chosen to fragment and produce tandem mass spectra, which can be identified by database search, and then proteins can be inferred from the identified peptides. In the identification, precursor mass is a key parameter. Whether the correct peptide is within the peptide candidates depends on whether the precursor mass is the monoisotopic mass. The number of peptide candidates depends on the accuracy of the precursor mass. This research investigates the accurate determination of precursors in terms of monoisotopic peak determination and systematic error elimination. There are some techniques of monoisotopic peak determination on protein level, including charge state determination, monoisotopic peak determination and overlapping cluster determination. Some of them can be used to the monoisotopic peak determination of precursors. Meanwhile, there are some well-known methods for systematic error elimination. The two kinds of techniques for accurate precursor determination can help increase the large-scale protein identification rate.