Analysis of virion associated host proteins in vesicular stomatitis virus using a proteomics approach

<p>Abstract</p> <p>Background</p> <p>Vesicular stomatitis virus (VSV) is the prototypic rhabdovirus and the best studied member of the order <it>Mononegavirales</it>. There is now compelling evidence that enveloped virions released from infected cells carry numerous host (cellular) proteins some of which may play an important role in viral replication. Although several cellular proteins have been previously shown to be incorporated into VSV virions, no systematic study has been done to reveal the host protein composition for virions of VSV or any other member of <it>Mononegavirales</it>.</p> <p>Results</p> <p>Here we used a proteomics approach to identify cellular proteins within purified VSV virions, thereby creating a "snapshot" of one stage of virus/host interaction that can guide future experiments aimed at understanding molecular mechanisms of virus-cell interactions. Highly purified preparations of VSV virions from three different cell lines of human, mouse and hamster origin were analyzed for the presence of cellular proteins using mass spectrometry. We have successfully confirmed the presence of several previously-identified cellular proteins within VSV virions and identified a number of additional proteins likely to also be present within the virions. In total, sixty-four cellular proteins were identified, of which nine were found in multiple preparations. A combination of immunoblotting and proteinase K protection assay was used to verify the presence of several of these proteins (integrin β1, heat shock protein 90 kDa, heat shock cognate 71 kDa protein, annexin 2, elongation factor 1a) within the virions.</p> <p>Conclusion</p> <p>This is, to our knowledge, the first systematic study of the host protein composition for virions of VSV or any other member of the order <it>Mononegavirales</it>. Future experiments are needed to determine which of the identified proteins have an interaction with VSV and whether these interactions are beneficial, neutral or antiviral with respect to VSV replication. Identification of host proteins-virus interactions beneficial for virus would be particularly exciting as they can provide new ways to combat viral infections via control of host components.</p

Mitochondrial function contributes to oxysterol-induced osteogenic differentiation in mouse embryonic stem cells

AbstractOxysterols, oxidized derivatives of cholesterol, are biologically active molecules. Specific oxysterols have potent osteogenic properties that act on osteoprogenitor cells. However, the molecular mechanisms underlying these osteoinductive effects on embryonic stem cells (ESCs) are unknown. This study investigated the effect of an oxysterol combination of 22(S)-hydroxycholesterol and 20(S)-hydroxycholesterol (SS) on osteogenic differentiation of ESCs and the alterations to mitochondrial activity during differentiation. Osteogenic differentiation was assessed by alkaline phosphatase (ALP) activity, matrix mineralization, mRNA expression of osteogenic factors, runt-related transcription factor 2, osterix, and osteocalcin, and protein levels of collagen type IA (COLIA) and osteopontin (OPN). Treatment of cells with SS increased osteoinductive activity compared to the control group. Intracellular reactive oxygen species production, intracellular ATP content, mitochondrial membrane potential, mitochondrial mass, mitochondrial DNA copy number, and mRNA expression of peroxisome proliferator-activated receptor-γ coactivators 1α and β, transcription factors involved in mitochondrial biogenesis, were significantly increased during osteogenesis, indicating upregulation of mitochondrial activity. Oxysterol combinations also increased protein levels of mitochondrial respiratory complexes I–V. We also found that SS treatment increased hedgehog signaling target genes, Smo and Gli1 expression. Inhibition of Hh signaling by cyclopamine suppressed mitochondrial biogenesis and ESC osteogenesis. Subsequently, oxysterol-induced Wnt/β-catenin pathways were inhibited by repression of Hh signaling and mitochondrial biogenesis. Transfection of β-catenin specific siRNA decreased the protein levels of COLIA and OPN, as well as ALP activity. Collectively, these data suggest that lipid-based oxysterols enhance differentiation of ESCs toward the osteogenic lineage by regulating mitochondrial activity, canonical Hh/Gli, and Wnt/β-catenin signaling

Akt1-Inhibitor of DNA binding2 is essential for growth cone formation and axon growth and promotes central nervous system axon regeneration.

Mechanistic studies of axon growth during development are beneficial to the search for neuron-intrinsic regulators of axon regeneration. Here, we discovered that, in the developing neuron from rat, Akt signaling regulates axon growth and growth cone formation through phosphorylation of serine 14 (S14) on Inhibitor of DNA binding 2 (Id2). This enhances Id2 protein stability by means of escape from proteasomal degradation, and steers its localization to the growth cone, where Id2 interacts with radixin that is critical for growth cone formation. Knockdown of Id2, or abrogation of Id2 phosphorylation at S14, greatly impairs axon growth and the architecture of growth cone. Intriguingly, reinstatement of Akt/Id2 signaling after injury in mouse hippocampal slices redeemed growth promoting ability, leading to obvious axon regeneration. Our results suggest that Akt/Id2 signaling is a key module for growth cone formation and axon growth, and its augmentation plays a potential role in CNS axonal regeneration

A simple and accurate SNP scoring strategy based on typeIIS restriction endonuclease cleavage and matrix-assisted laser desorption/ionization mass spectrometry

<p>Abstract</p> <p>Background</p> <p>We describe the development of a novel matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF)-based single nucleotide polymorphism (SNP) scoring strategy, termed Restriction Fragment Mass Polymorphism (RFMP) that is suitable for genotyping variations in a simple, accurate, and high-throughput manner. The assay is based on polymerase chain reaction (PCR) amplification and mass measurement of oligonucleotides containing a polymorphic base, to which a typeIIS restriction endonuclease recognition was introduced by PCR amplification. Enzymatic cleavage of the products leads to excision of oligonucleotide fragments representing base variation of the polymorphic site whose masses were determined by MALDI-TOF MS.</p> <p>Results</p> <p>The assay represents an improvement over previous methods because it relies on the direct mass determination of PCR products rather than on an indirect analysis, where a base-extended or fluorescent report tag is interpreted. The RFMP strategy is simple and straightforward, requiring one restriction digestion reaction following target amplification in a single vessel. With this technology, genotypes are generated with a high call rate (99.6%) and high accuracy (99.8%) as determined by independent sequencing.</p> <p>Conclusion</p> <p>The simplicity, accuracy and amenability to high-throughput screening analysis should make the RFMP assay suitable for large-scale genotype association study as well as clinical genotyping in laboratories.</p

Gene Expression Profile of the Hypothalamus in DNP-KLH Immunized Mice Following Electroacupuncture Stimulation

Clinical evidence indicates that electroacupuncture (EA) is effective for allergic disorder. Recent animal studies have shown that EA treatment reduces levels of IgE and Th2 cytokines in BALB/c mice immunized with 2,4-dinitrophenylated keyhole limpet protein (DNP-KLH). The hypothalamus, a brain center of the neural-immune system, is known to be activated by EA stimulation. This study was performed to identify and characterize the differentially expressed genes in the hypothalamus of DNP-KLH immunized mice that were stimulated with EA or only restrained. To this aim, we conducted a microarray analysis to evaluate the global gene expression profiles, using the hypothalamic RNA samples taken from three groups of mice: (i) normal control group (no treatments); (ii) IMH group (DNP-KLH immunization + restraint); and (iii) IMEA group (immunization + EA stimulation). The microarray analysis revealed that total 39 genes were altered in their expression levels by EA treatment. Ten genes, including T-cell receptor alpha variable region family 13 subfamily 1 (Tcra-V13.1), heat shock protein 1B (Hspa1b) and 2′–5′ oligoadenylate synthetase 1F (Oas1f), were up-regulated in the IMEA group when compared with the IMH group. In contrast, 29 genes, including decay accelerating factor 2 (Daf2), NAD(P)H dehydrogenase, quinone 1 (Nqo1) and programmed cell death 1 ligand 2 (Pdcd1lg2) were down-regulated in the IMEA group as compared with the IMH group. These results suggest that EA treatment can modulate immune response in DNP-KLH immunized mice by regulating expression levels of genes that are associated with innate immune, cellular defense and/or other kinds of immune system in the hypothalamus

Endometrial Stromal Sarcoma Presenting as Prevesical Mass Mimicking Urachal Tumor

Endometrial stromal sarcoma (ESS) is a mesenchymal neoplasm that usually occurs as a primary tumor of the uterine corpus, but rarely arises in other sites, such as the ovary, pelvic cavity, mesentery, omentum and intestine. Herein, we present a rare case of low-grade ESS presented as prevesical mass. A 60-yr-old woman who had undergone total hysterectomy for endometriosis eleven years ago was presented with incidentally detected prevesical pelvic mass. Since malignant transformation of urachal remnants was possible, the mass was suspected to be a urachal tumor. Extraction of the mass was performed, and the histopathologic diagnosis was low-grade ESS. In summary, prevesical tumor is rare but in patients with endometriosis, we suggest endometriosis and its possible malignant changes should be taken into account in the differential diagnosis of prevesical mass

Relationships between Tumor Volume and Lymphatic Metastasis and Prognosis in Early Oral Tongue Cancer

ObjectivesAlthough T stage is an important prognostic tool for oral tongue cancer, it fails to define the depth of invasion and true three-dimensional volume of primary tumors. The purpose of this paper is to determine the relations between tumor volume and lymph node metastasis and survival in early oral tongue cancer.MethodsForty-seven patients with T1-2 tongue cancer were included. Tumor volumes were measured by the computerized segmentation of T2-weighted magnetic resonance imaging.ResultsThe overall average tumor volume was 27.7 cm3 (range, 1.4 to 60.1 cm3). A significant positive correlation was found between tumor volume and pathological T stage, depth of invasion, and cervical lymph node metastasis (P<0.001, P<0.001, and P=0.002, respectively). When the tumor volume exceeded 20 cm3, the cervical metastasis rate increased to 69.2%. The overall 5-year disease specific survival rate was 80%. There was a statistically significant association between large tumor volume (≥20 cm3) and the 5-year disease-specific survival (P=0.046).ConclusionTumor volume larger than 20 cm3 was associated with greater risk cervical lymph node metastasis and poor 5-year disease-specific survival rate in early oral tongue cancer patients