Role of Virus-Encoded microRNAs in Avian Viral Diseases

To survive in the host cells, viruses have to adapt various strategies, which include the modulation of microRNA (miRNA) pathway through virus-encoded miRNAs to modulate the host cellular environment. It has been shown that several avian viruses, mostly herpesviruses, encode a number of miRNAs. These include 26 miRNAs encoded by the highly oncogenic Marek’s disease virus-1, 36 miRNAs encoded by avirulent Marek’s disease virus-2, 28 miRNAs by herpesvirus of turkeys, 10 miRNAs by infectious laryngotracheitis virus, 41 miRNAs by duck enteritis virus, and 2 miRNAs by avian leukosis virus subgroup J. Although locations of some of the miRNAs are conserved within the repeat regions of the genomes among some of the antigenic and phylogenetic closely related herpesviruses, there are no sequence conservation of miRNAs encoded by different avian herpesviruses. Moreover, some of the virus-encoded miRNAs have the same seed sequence as host miRNAs serve as functional orthologs. For example, mdv1-miR-M4-5p, a functional ortholog of gga-miR-155, is critical for the Marek’s disease virus in inducing tumors. In this review, we describe the advances in our understanding on the role of the herpesvirus-encoded miRNAs in avian diseases. Additionally, we also describe the potential association of avian leukosis virus subgroup J encoded E (XSR) miRNA in the induction of myeloid tumors in certain genetically distinct chicken lines

Neural activity dissociation between thought-based and perception-based response conflict

Based on the idea that intentions have different penetrability to perception and thought (Fodor, 1983), four Stroop-like tasks, AA, AW, WA, and WW are used, where the A represents an arrow and the CPPR (closest processing prior to response) is perception, and the W represents a word and the CPPR is thought. Event-related brain potentials were recorded as participants completed these tasks, and sLORETA (standardized low resolution brain electromagnetic tomography) was used to localize the sources at specific time points. These results showed that there is an interference effect in the AA and WA tasks, but not in the AW or WW tasks. The activated brain areas related to the interference effect in the AA task were the PFC and ACC, and PFC activation took place prior to ACC activation; but only PFC in WA task. Combined with previous results, a new neural mechanism of cognitive control is proposed

MicroRNA-26a-mediated regulation of interleukin-2 expression in transformed avian lymphocyte lines

<p>Abstract</p> <p>Background</p> <p>Micro(mi)RNAs are a class of small non-coding RNAs that play critical roles in the induction of various cancers, including lymphomas induced by oncogenic viruses. While some of the miRNAs are oncogenic, miRNAs such as miR-26a are consistently downregulated in a number of cancers, demonstrating their potential tumor suppressor functions. Global miRNA expression profiles of a number of virus-transformed avian lymphoma cell lines have shown downregulation of gga-miR-26a expression, irrespective of molecular mechanisms of transformation or the viral aetiology. The neoplastic transformation of lymphocytes by many viruses accompanies high levels of proliferative responses, mostly mediated through cytokines such as IL-2. Chicken IL-2 can modulate T-cell proliferation and cytotoxicity <it>in vitro </it>and <it>in vivo </it>and dysregulation of IL-2 expression is observed in diseases such as leukaemia.</p> <p>Results</p> <p>The expression levels of gga-miR-26a in chicken lymphoma cells transformed by 3 distinct avian oncogenic viruses, <it>viz </it>Marek's disease virus (MDV), avian leukosis virus (ALV) and Reticuloendotheliosis virus (REV) were consistently downregulated compared to the levels in the normal lymphocytes. This downregulation of miR-26a regardless of the viral etiology and molecular mechanisms of transformation was consistent with the tumor suppressor role of this miRNA. Notwithstanding this well-established role in cancer, we demonstrate the additional role of this miRNA in directly targeting chicken IL-2 through reporter and biochemical assays. The downregulation of miR-26a can relieve the suppressive effect of this miRNA on IL-2 expression.</p> <p>Conclusions</p> <p>We show that miR-26a is globally downregulated in a number of avian lymphoma cells irrespective of the mechanisms of transformation, reiterating the highly conserved tumor suppressor function of this miRNA. However, with the potential for directly targeting chicken IL-2, the downregulation of miR-26a in these tumor cells could relieve the inhibitory effect on IL-2 expression assisting in the proliferative features of the transformed lymphocyte lines.</p

Left hemisphere predominance of pilocarpine-induced rat epileptiform discharges

<p>Abstract</p> <p>Background</p> <p>The left cerebral hemisphere predominance in human focal epilepsy has been observed in a few studies, however, there is no related systematic study in epileptic animal on hemisphere predominance. The main goal of this paper is to observe if the epileptiform discharges (EDs) of Pilocarpine-induced epileptic rats could present difference between left hemisphere and right hemisphere or not.</p> <p>Methods</p> <p>The electrocorticogram (ECoG) and electrohippocampogram (EHG) from Pilocarpine-induced epileptic rats were recorded and analyzed using Synchronization likelihood (SL) in order to determine the synchronization relation between different brain regions, then visual check and cross-correlation analysis were adopted to evaluate if the EDs were originated more frequently from the left hemisphere than the right hemisphere.</p> <p>Results</p> <p>The data show that the synchronization between left-EHG and right-EHG, left-ECoG and left-EHG, right-ECoG and right-EHG, left-ECoG and right-ECoG, are significantly strengthened after the brain functional state transforms from non-epileptiform discharges to continuous-epileptiform discharges(p < 0.05). When the state transforms from continuous EDs to periodic EDs, the synchronization is significantly weakened between left-ECoG and left-EHG, left-EHG and right-EHG (p < 0.05). Visual check and the time delay (τ) based cross-correlation analysis finds that 10 out of 13 EDs have a left predominance (77%) and 3 out of 13 EDs are right predominance (23%).</p> <p>Conclusion</p> <p>The results suggest that the left hemisphere may be more prone to EDs in the Pilocarpine-induced rat epilepsy model and implicate that the left hemisphere might play an important role in epilepsy states transition.</p

MicroRNA expression profiles in avian haemopoietic cells

MicroRNAs (miRNAs) are small, abundant, non-coding RNAs that modulate gene expression by interfering with translation or stability of mRNA transcripts in a sequence-specific manner. A total of 734 precursor and 996 mature miRNAs have so far been identified in the chicken genome. A number of these miRNAs are expressed in a cell type-specific manner, and understanding their function requires detailed examination of their expression in different cell types. We carried out deep sequencing of small RNA populations isolated from stimulated or transformed avian haemopoietic cell lines to determine the changes in the expression profiles of these important regulatory molecules during these biological events. There were significant changes in the expression of a number of miRNAs, including miR-155, in chicken B cells stimulated with CD40 ligand. Similarly, avian leukosis virus (ALV)-transformed DT40 cells also showed changes in miRNA expression in relation to the na&#239;ve cells. Embryonic stem cell line BP25 demonstrated a distinct cluster of upregulated miRNAs, many of which were shown previously to be involved in embryonic stem cell development. Finally, chicken macrophage cell line HD11 showed changes in miRNA profiles, some of which are thought to be related to the transformation by v-myc transduced by the virus. This work represents the first publication of a catalog of microRNA expression in a range of important avian cells and provides insights into the potential roles of miRNAs in the hematopoietic lineages of cells in a model non-mammalian species

Marek's disease virus-encoded miR-155 ortholog critical for the induction of lymphomas is not essential for the proliferation of transformed cell lines

MicroRNAs (miRNAs) are small noncoding RNAs with profound regulatory roles in many areas of biology, including cancer. MicroRNA 155 (miR-155), one of the extensively studied multifunctional miRNAs, is important in several human malignancies such as diffuse large B cell lymphoma and chronic lymphocytic leukemia. Moreover, miR-155 orthologs KSHV-miR-K12-11 and MDV-miR-M4, encoded by Kaposi's sarcoma-associated herpesvirus (KSHV) and Marek's disease virus (MDV), respectively, are also involved in oncogenesis. In MDV-induced T-cell lymphomas and in lymphoblastoid cell lines derived from them, MDV-miR-M4 is highly expressed. Using excellent disease models of infection in natural avian hosts, we showed previously that MDV-miR-M4 is critical for the induction of T-cell lymphomas as mutant viruses with precise deletions were significantly compromised in their oncogenicity. However, those studies did not elucidate whether continued expression of MDV-miR-M4 is essential for maintaining the transformed phenotype of tumor cells. Here using an in situ CRISPR/Cas9 editing approach, we deleted MDV-miR-M4 from the MDV-induced lymphoma-derived lymphoblastoid cell line MDCC-HP8. Precise deletion of MDV-miR-M4 was confirmed by PCR, sequencing, quantitative reverse transcription-PCR (qRT-PCR), and functional analysis. Continued proliferation of the MDV-miR-M4-deleted cell lines demonstrated that MDV-miR-M4 expression is not essential for maintaining the transformed phenotype, despite its initial critical role in the induction of lymphomas. Ability to examine the direct role of oncogenic miRNAs in situ in tumor cell lines is valuable in delineating distinct determinants and pathways associated with the induction or maintenance of transformation in cancer cells and will also contribute significantly to gaining further insights into the biology of oncogenic herpesviruses.IMPORTANCE Marek's disease virus (MDV) is an alphaherpesvirus associated with Marek's disease (MD), a highly contagious neoplastic disease of chickens. MD serves as an excellent model for studying virus-induced T-cell lymphomas in the natural chicken hosts. Among the limited set of genes associated with MD oncogenicity, MDV-miR-M4, a highly expressed viral ortholog of the oncogenic miR-155, has received extensive attention due to its direct role in the induction of lymphomas. Using a targeted CRISPR-Cas9-based gene editing approach in MDV-transformed lymphoblastoid cell lines, we show that MDV-miR-M4, despite its critical role in the induction of tumors, is not essential for maintaining the transformed phenotype and continuous proliferation. As far as we know, this was the first study in which precise editing of an oncogenic miRNA was carried out in situ in MD lymphoma-derived cell lines to demonstrate that it is not essential in maintaining the transformed phenotype

La profesión de dietista

En la preocupación que ROL demuestra por clarificar los campos de la 'Enfermería', sus especialidades y profesiones paralelas, nos brinda un espacio para presentar la comunicación que sobre 'La profesión de Dietista', expusimos en el 1.er Congreso de la Sociedad Española de Nutrición, celebrado en Galicia en octubre de 1979. La nutrición aplicada, o sea la DIETÉTICA, al igual que las ciencias de la alimentación, relativamente modernas, están en continua evolución. Por esto, no es de extrañar el desconocimiento de la profesión de 'Dietista', que por parte oficial observamos en nuestro país y que nos ha inducido a presentar esta ponencia

Establishment and application of a VP3 antigenic domain-based peptide ELISA for the detection of antibody against goose plague virus infection

The detection of antibody against goose plague virus (GPV) infection has never had a commercialized test kit, which has posed challenges to the prevention and control of this disease. In this study, bioinformatics software was used to analyze and predict the dominant antigenic regions of the main protective antigen VP3 of GPV. Three segments of bovine serum albumin (BSA) vector-coupled peptides were synthesized as ELISA coating antigens. Experimental results showed that the VP3-1 (358-392aa) peptide had the best reactivity and specificity. By using the BSA-VP3-1 peptide, a detection method for antibody against GPV infection was established, demonstrating excellent specificity with no cross-reactivity with common infectious goose pathogen antibodies. The intra-batch coefficient of variation and inter-batch coefficient of variation were both less than 7%, indicating good stability and repeatability. The dynamic antibody detection results of gosling vaccines and the testing of 120 clinical immune goose serum samples collectively demonstrate that BSA-VP3-1 peptide ELISA can be used to detect antibody against GPV in the immunized goose population and has higher sensitivity than traditional agar gel precipitation methods. Taken together, the developed peptide-ELISA based on VP3 358-392aa could be useful in laboratory viral diagnosis, routine surveillance in goose farms. The main application of the peptide-ELISA is to monitor the antibody level and vaccine efficacy for GPV, which will help the prevention and control of gosling plague

Critical Role of the Virus-Encoded MicroRNA-155 Ortholog in the Induction of Marek's Disease Lymphomas

Notwithstanding the well-characterised roles of a number of oncogenes in neoplastic transformation, microRNAs (miRNAs) are increasingly implicated in several human cancers. Discovery of miRNAs in several oncogenic herpesviruses such as KSHV has further highlighted the potential of virus-encoded miRNAs to contribute to their oncogenic capabilities. Nevertheless, despite the identification of several possible cancer-related genes as their targets, the direct in vivo role of virus-encoded miRNAs in neoplastic diseases such as those induced by KSHV is difficult to demonstrate in the absence of suitable models. However, excellent natural disease models of rapid-onset Marek's disease (MD) lymphomas in chickens allow examination of the oncogenic potential of virus-encoded miRNAs. Using viruses modified by reverse genetics of the infectious BAC clone of the oncogenic RB-1B strain of MDV, we show that the deletion of the six-miRNA cluster 1 from the viral genome abolished the oncogenicity of the virus. This loss of oncogenicity appeared to be primarily due to the single miRNA within the cluster, miR-M4, the ortholog of cellular miR-155, since its deletion or a 2-nucleotide mutation within its seed region was sufficient to inhibit the induction of lymphomas. The definitive role of this miR-155 ortholog in oncogenicity was further confirmed by the rescue of oncogenic phenotype by revertant viruses that expressed either the miR-M4 or the cellular homolog gga-miR-155. This is the first demonstration of the direct in vivo role of a virus-encoded miRNA in inducing tumors in a natural infection model. Furthermore, the use of viruses deleted in miRNAs as effective vaccines against virulent MDV challenge, enables the prospects of generating genetically defined attenuated vaccines