IFI207, a young and fast-evolving protein, controls retroviral replication via the STING pathway.

Mammalian AIM-2-like receptor (ALR) proteins bind nucleic acids and initiate production of type I interferons or inflammasome assembly, thereby contributing to host innate immunity. In mice, the Alr locus is highly polymorphic at the sequence and copy number level, and we show here that it is one of the most dynamic regions of the genome. One rapidly evolving gene within this region, Ifi207, was introduced to the Mus genome by gene conversion or an unequal recombination event a few million years ago. Ifi207 has a large, distinctive repeat region that differs in sequence and length among Mus species and even closely related inbred Mus musculus strains. We show that IFI207 controls murine leukemia virus (MLV) infection in vivo and that it plays a role in the STING-mediated response to cGAMP, dsDNA, DMXXA, and MLV. IFI207 binds to STING, and inclusion of its repeat region appears to stabilize STING protein. The Alr locus and Ifi207 provide a clear example of the evolutionary innovation of gene function, possibly as a result of host-pathogen co-evolution.IMPORTANCEThe Red Queen hypothesis predicts that the arms race between pathogens and the host may accelerate evolution of both sides, and therefore causes higher diversity in virulence factors and immune-related proteins, respectively . The Alr gene family in mice has undergone rapid evolution in the last few million years and includes the creation of two novel members, MndaL and Ifi207. Ifi207, in particular, became highly divergent, with significant genetic changes between highly related inbred mice. IFI207 protein acts in the STING pathway and contributes to anti-retroviral resistance via a novel mechanism. The data show that under the pressure of host-pathogen coevolution in a dynamic locus, gene conversion and recombination between gene family members creates new genes with novel and essential functions that play diverse roles in biological processes.

Murine leukemia virus infection of non-dividing dendritic cells is dependent on nucleoporins.

Retroviral reverse transcription starts within the capsid and uncoating and reverse transcription are mutually dependent. There is still debate regarding the timing and cellular location of HIV's uncoating and reverse transcription and whether it occurs solely in the cytoplasm, nucleus or both. HIV can infect non-dividing cells because there is active transport of the preintegration complex (PIC) across the nuclear membrane, but Murine Leukemia Virus (MLV) is thought to depend on cell division for replication and whether MLV uncoating and reverse transcription is solely cytoplasmic has not been studied. Here, we used NIH3T3 and primary mouse dendritic cells to determine where the different stages of reverse transcription occur and whether cell division is needed for nuclear entry. Our data strongly suggest that in both NIH3T3 cells and dendritic cells (DCs), the initial step of reverse transcription occurs in the cytoplasm. However, we detected MLV RNA/DNA hybrid intermediates in the nucleus of dividing NIH3T3 cells and non-dividing DCs, suggesting that reverse transcription can continue after nuclear entry. We also confirmed that the MLV PIC requires cell division to enter the nucleus of NIH3T3 cells. In contrast, we show that MLV can infect non-dividing primary DCs, although integration of MLV DNA in DCs still required the viral p12 protein. Knockdown of several nuclear pore proteins dramatically reduced the appearance of integrated MLV DNA in DCs but not NIH3T3 cells. Additionally, MLV capsid associated with the nuclear pore proteins NUP358 and NUP62 during infection. These findings suggest that simple retroviruses, like the complex retrovirus HIV, gain nuclear entry by traversing the nuclear pore complex in non-mitotic cells.

Phosphoproteome Reveals Extracellular Regulated Protein Kinase Phosphorylation Mediated by Mitogen-Activated Protein Kinase Kinase-Regulating Granulosa Cell Apoptosis in Broody Geese.

Geese have strong brooding abilities, which severely affect their egg-laying performance. Phosphorylation is widely involved in regulating reproductive activities, but its role in goose brooding behavior is unclear. In this study, we investigated differences in the phosphoprotein composition of ovarian tissue between laying and brooding geese. Brooding geese exhibited ovarian and follicular atrophy, as well as significant oxidative stress and granulosa cell apoptosis. We identified 578 highly phosphorylated proteins and 281 lowly phosphorylated proteins, and a KEGG pathway analysis showed that these differentially phosphorylated proteins were mainly involved in cell apoptosis, adhesion junctions, and other signaling pathways related to goose brooding behavior. The extracellular regulated protein kinase (ERK)-B-Cell Lymphoma 2(BCL2) signaling pathway was identified as playing an important role in regulating cell apoptosis. The phosphorylation levels of ERK proteins were significantly lower in brooding geese than in laying geese, and the expression of mitogen-activated protein kinase kinase (MEK) was downregulated. Overexpression of MEK led to a significant increase in ERK phosphorylation and BCL2 transcription in H2O2-induced granulosa cells (p < 0.05), partially rescuing cell death. Conversely, granulosa cells receiving MEK siRNA exhibited the opposite trend. In conclusion, geese experience significant oxidative stress and granulosa cell apoptosis during brooding, with downregulated MEK expression, decreased phosphorylation of ERK protein, and inhibited expression of BCL2.

MACdb: A Curated Knowledgebase for Metabolic Associations across Human Cancers.

Cancer is one of the leading causes of human death. As metabolomics techniques become more and more widely used in cancer research, metabolites are increasingly recognized as crucial factors in both cancer diagnosis and treatment. In this study, we developed MACdb (https://ngdc.cncb.ac.cn/macdb), a curated knowledgebase to recruit the metabolic associations between metabolites and cancers. Unlike conventional data-driven resources, MACdb integrates cancer-metabolic knowledge from extensive publications, providing high quality metabolite associations and tools to support multiple research purposes. In the current implementation, MACdb has integrated 40,710 cancer-metabolite associations, covering 267 traits from 17 categories of cancers with high incidence or mortality, based entirely on manual curation from 1,127 studies reported in 462 publications (screened from 5,153 research papers). MACdb offers intuitive browsing functions to explore associations at multi-dimensions (metabolite, trait, study, and publication), and constructs knowledge graph to provide overall landscape among cancer, trait, and metabolite. Furthermore, NameToCid (map metabolite name to PubChem Cid) and Enrichment tools are developed to help users enrich the association of metabolites with various cancer types and traits. IMPLICATION: MACdb paves an informative and practical way to evaluate cancer-metabolite associations and has a great potential to help researchers identify key predictive metabolic markers in cancers.

YKL-40 as a novel biomarker related to white matter damage and cognitive impairment in patients with cerebral small vessel disease.

YKL-40 is a novel neuroinflammatory marker associated with white matter damage and cognitive dysfunction. 110 CSVD patients, including 54 with mild cognitive impairment (CSVD-MCI), 56 with no cognitive impairment (CSVD-NCI), and 40 healthy controls (HCs) underwent multimodal magnetic resonance examination, serum YKL-40 level detection and cognitive function assessment to investigate the association between YKL-40 and white matter damage and cognitive impairment in cerebral small vessel disease (CSVD) patients. White matter hyperintensities volume was calculated using the Wisconsin White Matter Hyperintensity Segmentation Toolbox (W2MHS) for white matter macrostructural damage evaluation. For white matter microstructural damage evaluation, fractional anisotropy (FA) and mean diffusivity (MD) indices of the region of interest were analyzed based on diffusion tensor imaging (DTI) images using the Tract-Based Spatial Statistics (TBSS) pipeline. The serum YKL-40 level of CSVD was significantly higher than those of HCs, and the CSVD-MCI was higher than in HCs and CSVD-NCI. Furthermore, serum YKL-40 provided high diagnostic accuracy for CSVD and CSVD-MCI. The macroscopic and microstructure of white matter in CSVD-NCI and CSVD-MCI patients indicated different degrees of damage. Disruption of white matter macroscopic and microstructure was significantly associated with YKL-40 levels and cognition deficits. Moreover, the white matter damage mediated the associations between the increased serum YKL-40 levels and cognitive impairment. Our findings demonstrated that YKL-40 might be a potential biomarker of white matter damage in CSVD, whereas white matter damage was associated with cognitive impairment. Serum YKL-40 measurement provides complementary information regarding the neural mechanism of CSVD and its associated cognitive impairment.

Altered serum amyloid beta and cerebral perfusion and their associations with cognitive function in patients with subcortical ischemic vascular disease.

Subcortical ischemic vascular disease (SIVD) is one of the important causes of cognitive dysfunction, altered amyloid-beta (Aß) and cerebral perfusion may be involved in the pathophysiological mechanism of SIVD and are closely related to cognitive function. We aimed to investigate altered serum Aß and cerebral perfusion in patients with SIVD and their correlation with cognitive function. Seventy-four healthy controls (HCs) and 74 SIVD patients, including 38 SIVD patients with no cognitive impairment (SIVD-NCI) and 36 SIVD patients with mild cognitive impairment (SIVD-MCI) underwent the measurement of serum Aß40 and Aß42 levels, pseudo-continuous arterial spin labeling MRI scanning, and cognitive evaluation. Compared to the healthy controls (HCs), the level of serum Aß40 and Aß40/42 ratio increased and Aß42 decreased in SIVD patients. The serum Aß40 level and Aß40/42 ratio in patients with SIVD-MCI were significantly higher than those in the HCs and SIVD-NCI, and the level of Aß42 in the SIVD-MCI was lower than the HCs. In addition, the serum Aß40/42 ratio provided high diagnostic accuracy for SIVD and SIVD-MCI, it was further identified as an independent risk factor for cognitive impairment. Patients with SIVD-NCI and SIVD-MCI exhibited both increased and decreased cerebral blood flow (CBF) in regional. The Aß40/42 ratio was associated with global CBF, while altered global and regional CBF was associated with cognitive deficits. In addition, white matter hyperintensities volume (WMHV) correlated with Aß40/42 ratio, CBF, and cognition. The relationship between Aß40/42 ratio and cognition was partially mediated by altered CBF. Based on these results, we conclude that the serum Aß40/42 ratio may be a potential biomarker that can complement current methods for the prediction and diagnosis of cognitive impairment in SIVD patients. In addition, serum Aß may play a role in cognitive function by regulating CBF, which provides new insights into the intervention, treatment, and prevention of cognitive impairment in SIVD.

Diagnosis and Prediction of Endometrial Carcinoma Using Machine Learning and Artificial Neural Networks Based on Public Databases.

Endometrial carcinoma (EC), a common female reproductive system malignant tumor, affects thousands of people with high morbidity and mortality worldwide. This study was aimed at developing a prediction model for the diagnosis of EC in the general population. First, we obtained datasets GSE63678, GSE106191, and GSE115810 from the Gene Expression Omnibus (GEO) database, dataset GSE17025 from the GEO database, and the RNA sequence of EC from The Cancer Genome Atlas (TCGA) database to constitute the training, test, and validation groups, respectively. Subsequently, the 96 most significantly differentially expressed genes (DEGs) were identified and analyzed for function and pathway enrichment in the training group. Next, we acquired the disease-specific genes by random forest and established an artificial neural network for the diagnosis. Receiver operating characteristic (ROC) curves were utilized to identify the signature across the three groups. Finally, immune infiltration was analyzed to reveal tumor-immune microenvironment (TIME) alterations in EC. The top 96 DEGs (77 down-regulated and 19 up-regulated genes) were primarily enriched in the interleukin-17 signaling pathway, protein digestion and absorption, and transcriptional misregulation in cancer. Subsequently, 14 characterizing genes of EC were identified by random forest. In the training, test, and validation groups, the artificial neural network was constructed with high diagnostic accuracies of 0.882, 0.864, and 0.839, respectively, and areas under the ROC curve (AUCs) of 0.928, 0.921, and 0.782, respectively. Finally, resting and activated mast cells were found to have increased in TIME. We constructed an artificial diagnostic model with excellent reliability for EC and uncovered variations in the immunological ecosystem of EC through integrated bioinformatics approaches, which might be potential diagnostic targets for EC.

Safety, tolerance, pharmacokinetic and pharmacodynamic properties of thrombopoietin mimetic peptide for injection in Chinese healthy volunteers: a randomized, placebo-controlled, double-blind study.

The thrombopoietin mimetic peptide for injection is a second-generation thrombopoietin receptor agonist (TPO-RA) used in the treatment of patients with immune thrombocytopenia. The aim of the present study was to assess the safety, tolerance, pharmacokinetic and pharmacodynamic properties of thrombopoietin mimetic peptide for injection in Chinese healthy volunteers. A randomized, placebo-controlled, double-blind, dose-escalation study was conducted in healthy Chinese subjects aged 18-50 years. Thirty subjects received single subcutaneous injection of 0.3 µg/kg, 1.0 µg/kg, 2.0 µg/kg thrombopoietin mimetic peptide or placebo. Thrombopoietin mimetic peptide was safe and well tolerated at doses of 0.3-2.0 µg/kg. There was no significant change in mean platelet count (PLT) from baseline at the 0.3 µg/kg or placebo groups. The mean PLT of subjects in the 1.0 µg/kg and 2.0 µg/kg groups peaked at day 12 (± 1), began to decline around day 17, and returned to the baseline level at day 28 (± 1). Platelet aggregation rates of the three dose groups showed no significant change before and after administration. Serum concentrations of thrombopoietin mimetic peptide in all subjects were below the quantization limit. This was the first study to demonstrate that subcutaneous injection of thrombopoietin mimetic peptide at doses of 0.3-2.0 µg/kg was safe and well tolerated in Chinese healthy subjects. As a second-generation TPO-RA, thrombopoietin mimetic peptide is effective at improving PLT after single subcutaneous injection at dose of ≥1 µg/kg.P lain l anguage s ummaryWhat is the context?● Immune thrombocytopenia (ITP) is a rare, serious autoimmune disorder characterized by low platelet count (PLT) without an alternate cause. The treatment goal of ITP is to increase the platelet count to a safe level that can stop active bleeding and reduce the risks of future bleeding.● Thrombopoietin receptor agonists (TPO-RAs, e.g. eltrombopag, avatrombopag, hetrombopag, and romiplostim) have shown high response rates in stimulating platelet production and reducing the risk of bleeding. TPO-RAs provide ITP patients with well-tolerated, long-term treatment choices.What is new?● The thrombopoietin mimetic peptide for injection is a new TPO-RAs developed by Shandong Quangang Pharmaceutical Co., Ltd. (China).● This study showed that thrombopoietin mimetic peptide is effective at improving PLT after a single subcutaneous injection.● The thrombopoietin mimetic peptide is safe and well-tolerated in Chinese healthy subjects.What is the impact?● This study provides evidence for the further development potential of the thrombopoietin mimetic peptide.

Relationship between illness duration, corpus callosum changes, and sustained attention dysfunction in major depressive disorder.

BACKGROUND: Illness duration is the main index of cumulative illness severity during depression progression. Corpus callosum (CC) damage is among the most replicated neurobiological findings in major depressive disorder (MDD). We aimed to investigate the nature and extent of the association between illness duration and CC changes. METHODS: Ninety-six MDD patients and 50 controls underwent diffusion and resting-state functional magnetic resonance imaging (fMRI). White matter micro-structure and inter-hemispheric functional connectivity were quantified by fractional anisotropy (FA) and voxel-mirrored homotopic connectivity (VMHC). The CC was reconstructed by tractography and divided into five sub-regions. The associations of illness duration with FA of each CC sub-region and voxel-wise VMHC were examined using correlation analyses. Also, we investigated the potential relationship between illness duration, CC changes, and clinical variables using mediation analyses. RESULTS: In MDD patients, longer illness duration was selectively associated with lower FA of CC sub-regions 2 [partial correlation coefficient (pr) =-0.269, P=0.009] and 5 (pr=-0.296, P=0.004) as well as higher VMHC in the supplementary motor areas (pr=0.378, P<0.001), precuneus (pr=0.384, P<0.001), and lingual gyrus (pr=0.373, P<0.001) connected by the affected CC sub-regions. Further subgroup analyses demonstrated pronounced FA decrease and VMHC increase in patients with illness duration over 20 years relative to healthy controls (HC) and other patient subgroups with shorter illness durations. Moreover, lower FA of CC sub-regions 2 and 5 mediated the association between longer illness duration and more severe sustained attention dysfunction. CONCLUSIONS: These findings provide evidence for compromised structure yet compensatory function of the CC with increasing depression illness duration, which may inform effective antidepressant treatment strategies at different disease stages.

Declined miR-181a-5p expression is associated with impaired natural killer cell development and function with aging.

MicroRNAs (miRNAs) regulate gene expression and thereby influence cell development and function. Numerous studies have shown the significant roles of miRNAs in regulating immune cells including natural killer (NK) cells. However, little is known about the role of miRNAs in NK cells with aging. We previously demonstrated that the aged C57BL/6 mice have significantly decreased proportion of mature (CD27- CD11b+ ) NK cells compared with young mice, indicating impaired maturation of NK cells with aging. Here, we performed deep sequencing of CD27+ NK cells from young and aged mice. Profiling of the miRNome (global miRNA expression levels) revealed that 49 miRNAs displayed a twofold or greater difference in expression between young and aged NK cells. Among these, 30 miRNAs were upregulated and 19 miRNAs were downregulated in the aged NK cells. We found that the expression level of miR-l8la-5p was increased with the maturation of NK cells, and significantly decreased in NK cells from the aged mice. Knockdown of miR-181a-5p inhibited NK cell development in vitro and in vivo. Furthermore, miR-181a-5p is highly conserved in mice and human. MiR-181a-5p promoted the production of IFN-γ and cytotoxicity in stimulated NK cells from both mice and human. Importantly, miR-181a-5p level markedly decreased in NK cells from PBMC of elderly people. Thus, our results demonstrated that the miRNAs profiles in NK cells change with aging, the decreased level of miR-181a-5p contributes to the defective NK cell development and function with aging. This opens new strategies to preserve or restore NK cell function in the elderly.

Mouse APOBEC3 Restriction of Retroviruses.

Apolipoprotein B mRNA editing enzyme, catalytic peptide 3 (APOBEC3) proteins are critical host proteins that counteract and prevent the replication of retroviruses. Unlike the genome of humans and other species, the mouse genome encodes a single Apobec3 gene, which has undergone positive selection, as reflected by the allelic variants found in different inbred mouse strains. This positive selection was likely due to infection by various mouse retroviruses, which have persisted in their hosts for millions of years. While mouse retroviruses are inhibited by APOBEC3, they nonetheless still remain infectious, likely due to the actions of different viral proteins that counteract this host factor. The study of viruses in their natural hosts provides important insight into their co-evolution.

Murine Leukemia Virus P50 Protein Counteracts APOBEC3 by Blocking Its Packaging.

Apolipoprotein B editing enzyme, catalytic polypeptide 3 (APOBEC3) family members are cytidine deaminases that play important roles in intrinsic responses to retrovirus infection. Complex retroviruses like human immunodeficiency virus type 1 (HIV-1) encode the viral infectivity factor (Vif) protein to counteract APOBEC3 proteins. Vif induces degradation of APOBEC3G and other APOBEC3 proteins and thereby prevents their packaging into virions. It is not known if murine leukemia virus (MLV) encodes a Vif-like protein. Here, we show that the MLV P50 protein, produced from an alternatively spliced gag RNA, interacts with the C terminus of mouse APOBEC3 and prevents its packaging without causing its degradation. By infecting APOBEC3 knockout (KO) and wild-type (WT) mice with Friend or Moloney MLV P50-deficient viruses, we found that APOBEC3 restricts the mutant viruses more than WT viruses in vivo Replication of P50-mutant viruses in an APOBEC3-expressing stable cell line was also much slower than that of WT viruses, and overexpressing P50 in this cell line enhanced mutant virus replication. Thus, MLV encodes a protein, P50, that overcomes APOBEC3 restriction by preventing its packaging into virions.IMPORTANCE MLV has existed in mice for at least a million years, in spite of the existence of host restriction factors that block infection. Although MLV is considered a simple retrovirus compared to lentiviruses, it does encode proteins generated from alternatively spliced RNAs. Here, we show that P50, generated from an alternatively spliced RNA encoded in gag, counteracts APOBEC3 by blocking its packaging. MLV also encodes a protein, glycoGag, that increases capsid stability and limits APOBEC3 access to the reverse transcription complex (RTC). Thus, MLV has evolved multiple means of preventing APOBEC3 from blocking infection, explaining its survival as an infectious pathogen in mice.

α-Santalol functionalized chitosan nanoparticles as efficient inhibitors of polo-like kinase in triple negative breast cancer.

Polo-like kinase 1 (PLK-1) is a protein kinase that plays a significant role in the initiation, maintenance, and completion of mitotic processes in the cell cycle. PLK-1 has been recorded to be over-expressed in various human cancers and is associated with poor prediction; thus it is an attractive target for anticancer therapy. Novel α-santalol functionalized chitosan nanoparticles were synthesized using the sol gel method and were assessed for their in vitro (MTT, apoptotic staining assays, and cell cycle analysis) and in vivo activities. α-Santalol loaded chitosan NPs inhibited the proliferation of triple negative breast cancer (MDA-MB-231) at an inhibitory concentration of (IC50) about 4.5 µg mL; meanwhile, in normal cells, no adverse effects were exhibited up to 100 µg mL-1. The findings also implicated a decreased expression of the anti-apoptotic protein, BCL-2 with PLK-1 and an increase in the expression of BAD, caspases and BAX. However, in in vivo studies, the treated animal group exhibited no aberrant effects in vital organs or blood parameters. Tumor growth was significantly inhibited after i.v. injection of α-santalol loaded chitosan NPs at a dose of 5 mg kg-1. Taken together, the α-santalol functionalized chitosan NPs hold great potential in biomedical applications, especially cancer theranostics, due to their versatile nature as well as diagnostics for clinical tumor biology.

MiR-942 regulates the function of breast cancer cell by targeting FOXA2.

MicroRNA (MiR)-942 regulates the development of a variety of tumors, however, its function in breast cancer (BCa) has been less reported. Therefore, the present study investigated the regulatory effects of miR-942 on BCa cells. The expression of miR-942 in whole blood samples and BCa cell lines was detected by quantitative real-time (qRT)-PCR. Direct target gene for miR-942 was confirmed by dual-luciferase reporter assay. FOXA2 expression in adjacent tissues was detected by qRT-PCR. The effects of miR-942, or miR-942 with FOXA2, on the cell viability, proliferation, apoptosis, migration and invasion of BCa cells were determined by cell counting kit-8 (CCK-8), colony formation assay, flow cytometry, wound scratch and Transwell, respectively. The levels of N-Cadherin, E-Cadherin and Snail were determined by Western blot. Kaplan-Meier was used to explore the relationship among the expressions of miR-942 and FOXA2 and the prognosis of BCa patients. MiR-942 had high expressed in BCa, while its low expression significantly suppressed the cell viability, proliferation, migration and invasion of BCa, but increased cell apoptosis. Down-regulation of N-Cadherin and Snail and up-regulation of E-Cadherin were also induced by low-expression of miR-942. FOXA2, which was proved as the direct target gene for miR-942 and was low-expressed in BCa, partially reversed the effect of overexpressed miR-942 on promoting cell viability, proliferation, migration and invasion, and suppressed cell apoptosis. A lower survival rate was observed in BCa patients with a high expression of miR-942 and a low expression of FOXA2. MiR-942 promoted the progression of BCa by down-regulating the expression of FOXA2.

Pineal gland abnormality in major depressive disorder.

Patients with major depressive disorder (MDD) often have circadian rhythm alteration and sleep disturbance. The pineal gland regulates the circadian rhythm and sleep by the secretion of melatonin neurohormone. However, the relationship between pineal abnormality and MDD remains elusive. 50 patients with MDD and 35 gender- and age-matched healthy controls underwent high-resolution structural MRI. Pineal parenchymal volume (PPV) was measured manually. Inter-group differences in prevalence of pineal cyst and PPV were examined. In addition, we investigated the correlations between PPV and symptom severity as well as sleep variables in the patient group. Compared to healthy controls, patients with MDD had a higher prevalence of pineal cyst. Moreover, patients had significantly decreased PPV relative to controls. However, no significant correlations were observed between PPV and symptom severity as well as sleep variables. Our findings suggest that pineal abnormality may play a critical role in depression.

Screening and bioinformatics analysis of circular RNA expression profiles in hepatitis B-related hepatocellular carcinoma.

BACKGROUND: Circular RNAs (circRNAs) play an important role in pathogenesis and development of hepatocellular carcinoma (HCC). However, circRNA expression profiles in hepatitis B Virus (HBV)-related HCC remain to be studied. METHODS: Total 13 HBV-related HCC patients were enrolled for study. Three HCC and 3 paired adjacent non-tumorous (NT) tissues from 3 patients were performed for microarray. Ten pairs of HCC tissues were used to verify the identified up-regulated and down-regulated circRNAs obtained from the microarray data by quantitative real-time reverse transcription PCR (qRT-PCR). Total RNA was isolated and treated with Rnase R to remove linear RNA, then hybridized to the array to screen for circRNAs. Bioinformatics analyses including clustering, differential expression, annotation of circRNA/microRNA (miRNA) interactions, Go analysis and KEGG pathway analysis, were performed. RESULTS: Based on the microarray data, we found significantly up-regulation of 24 circRNAs and down-regulation of 23 circRNAs in the HCC samples compared to NT samples (fold change ⩾ 2.0 and P< 0.05). Of them, 6 candidate circRNAs (hsa_circRNA_102814, 100381, 103489, 101764, 100327, and 103361) were verified by qRT-PCR. Of them, hsa_circRNA 100381, 103489 up-regulation and 101764 down-regulation were found to be significantly different in the 10 validation HCC tissue. Clusters of circRNAs were aberrantly expressed in HCC compared with NT samples. CircRNA_101764 was the largest nodes in circRNA/microRNA co-expression network, especially co-expression with hsa-miR-181 family, which plays an important role in cell network. Annotation of circRNA/miRNA interactions indicated that the biological effects of circRNA may be achieved by binding of miRNAs. GO analysis revealed that numerous target genes were involved in the biological processes, cellular component and molecular function. There was nearly 30 target genes enrichment on KEGG pathways analysis, PI3K-Akt signaling pathway which the most number of genes involved. CONCLUSION: In this study, we comprehensively explored the expression of differentially expressed circRNAs in HBV-related HCC, and our results indicate that circRNA_101764 may play an important role in the development of HCC.

Deaminase-Dead Mouse APOBEC3 Is an In Vivo Retroviral Restriction Factor.

The apolipoprotein B editing complex 3 (APOBEC3) proteins are potent retroviral restriction factors that are under strong positive selection, both in terms of gene copy number and sequence diversity. A common feature of all the members of the APOBEC3 family is the presence of one or two cytidine deamination domains, essential for cytidine deamination of retroviral reverse transcripts as well as packaging into virions. Several studies have indicated that human and mouse APOBEC3 proteins restrict retrovirus infection via cytidine deaminase (CD)-dependent and -independent means. To understand the relative contribution of CD-independent restriction in vivo, we created strains of transgenic mice on an APOBEC3 knockout background that express a deaminase-dead mouse APOBEC3 due to point mutations in both CD domains (E73Q/E253Q). Here, we show that the CD-dead APOBEC3 can restrict murine retroviruses in vivo Moreover, unlike the wild-type protein, the mutant APOBEC3 is not packaged into virions but acts only as a cell-intrinsic restriction factor that blocks reverse transcription by incoming viruses. Finally, we show that wild-type and CD-dead mouse APOBEC3 can bind to murine leukemia virus (MLV) reverse transcriptase. Our findings suggest that the mouse APOBEC3 cytidine deaminase activity is not required for retrovirus restriction.IMPORTANCE APOBEC3 proteins are important host cellular restriction factors essential for restricting retrovirus infection by causing mutations in the virus genome and by blocking reverse transcription. While both methods of restriction function in vitro, little is known about their role during in vivo infection. By developing transgenic mice with mutations in the cytidine deamination domains needed for enzymatic activity and interaction with viral RNA, we show that APOBEC3 proteins can still restrict in vivo infection by interacting with reverse transcriptase and blocking its activity. These studies demonstrate that APOBEC3 proteins have evolved multiple means for blocking retrovirus infection and that all of these means function in vivo.

Discovery of novel long non-coding RNAs induced by subgroup J avian leukosis virus infection in chicken.

Avian leukosis virus subgroup J (ALV-J) is an avian oncogenic retrovirus that has led to severe economic losses in the poultry industry in China in recent decades. Here, using high throughput transcriptome sequencing of HD11 and CEF cells infected with ALV-J, a set of 4804 novel long non-coding transcripts and numerous differentially expressed long non-coding RNAs (lncRNAs) were identified. We also found that they share relatively shorter transcripts and fewer exon numbers compared to mRNA. Correlation analysis suggested that many lncRNAs may activate gene expression in an enhancer-like manner other than through transcriptional regulation. Expression level analyses in vivo showed that three lncRNAs (NONGGAT001975.2, NONGGAT005832.2 and NONGGAT009792.2) may be associated with immune response regulation and could function as novel biomarkers for ALV-J infection. Our findings provides new insight into the pathological process of ALV-J infection and should serve as a high-quality resource for further research on epigenetic influences on disease-resistance breeding as well as immune system and genomic studies.

Aryl hydrocarbon receptor suppresses the osteogenesis of mesenchymal stem cells in collagen-induced arthritic mice through the inhibition of ß-catenin.

The contributions of aryl hydrocarbon receptor (Ahr) to the pathogenesis of rheumatoid arthritis (RA), particularly bone loss, have not been clearly explored. The imbalance between osteoblasts and osteoclasts is a major reason for bone loss. The dysfunction of osteoblasts, which are derived from mesenchymal stem cells (MSCs), induced bone erosion occurs earlier and is characterized as more insidious. Here, we showed that the nuclear expression and translocation of Ahr were both significantly increased in MSCs from collagen-induced arthritis (CIA) mice. The enhanced Ahr suppressed the mRNA levels of osteoblastic markers including Alkaline phosphatase (Alp) and Runt-related transcription factor 2 (Runx2) in the differentiation of MSCs to osteoblasts in CIA. The 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)-mediated activation of Ahr dose-dependently suppressed the expression of osteoblastic markers. In addition, the expression of ß-catenin was reduced in CIA MSCs compared with control, and the TCDD-mediated activation of the Ahr significantly inhibited ß-catenin expression. The Wnt3a-induced the activation of Wnt/ß-catenin pathway partly rescued the osteogenesis decline induced by TCDD. Taken together, these results indicate that activated Ahr plays a negative role in CIA MSCs osteogenesis, possibly by suppressing the expression of ß-catenin.

A Truncated IL-17RC Peptide Ameliorates Synovitis and Bone Destruction of Arthritic Mice.

Peptide-based therapy, such as modified peptides, has attracted increased attention. IL-17 is a promising therapeutic target for autoimmune diseases, and levels of circulating bioactive IL-17 are associated with rheumatoid arthritis severity. In this study, a modified truncated IL-17RC is generated to ameliorate inflammation and bone destruction in arthritis. The truncated IL-17RC binds to both IL-17A and IL-17F with higher binding capacity compared to nonmodified IL-17RC. In addition, the truncated IL-17RC reduces the secretion of inflammatory and osteoclastogenic factors induced by IL-17A/F in vitro. Moreover, the administration of truncated IL-17RC dramatically improves symptoms of inflammation and inhibited bone destruction in collagen-induced arthritis mice. Collectively, these data demonstrate that modified truncated IL-17RC peptide may be a more effective treatment strategy in the simultaneous inhibition of both IL-17A and IL-17F signaling, whereas the existing agents neutralize IL-17A or IL-17F alone. These suggest that the truncated IL-17RC may be a potential candidate in the treatment of inflammatory associated bone diseases.