• Elucidating these mechanisms and identifying which cellular factors are exploited by the retroviruses and which hinder their life cycle, will certainly lead to the discovery of new ways to inhibit viral replication and to improve retroviral vectors for gene transfer. (biomedcentral.com)
  • DNA sequences that form the coding region for retroviral enzymes including reverse transcriptase, protease, and endonuclease/integrase. (lookformedical.com)
  • The life cycle of retroviruses is arbitrarily divided into two distinct phases: the early phase refers to the steps of infection from cell binding to the integration of the viral cDNA into the cell genome, whereas the late phase begins with the expression of viral genes and continues through to the release and maturation of progeny virions (see Figure 1 for a schematic view of the retroviral life cycle). (biomedcentral.com)
  • The surge in Human Immunodeficiency Virus (HIV) research in order to identify new therapeutic targets has led to a better understanding of the retroviral life cycle. (biomedcentral.com)
  • The Env proteins of the Avian Sarcoma and Leukosis virus (ASLV) and the Murine Leukemia Virus (MLV) are both trimers of SU-TM heterodimers. (wikipedia.org)
  • DNA sequences that form the coding region for the viral envelope (env) proteins in retroviruses. (lookformedical.com)
  • The envelope consists of an inner layer of lipids and virus specified proteins also called membrane or matrix proteins. (lookformedical.com)
  • Proteins synthesized by HUMAN IMMUNODEFICIENCY VIRUSES such as the HIV-1 and HIV-2 . (lookformedical.com)
  • Much has been learned regarding nuclear entry, but the cellular proteins involved are still unknown and the exact role of each viral component remains controversial [ 7 ]. (biomedcentral.com)
  • In this study, we analyzed for the first time circRNAs expression profile and the biological function of these genes after FMDV infection of host cells. (biomedcentral.com)
  • The env gene codes for the gp160 protein which forms a homotrimer, and is cleaved into gp120 and gp41 by the host cell protease, furin. (wikipedia.org)
  • Env is a viral gene that encodes the protein forming the viral envelope. (wikipedia.org)
  • The mature product of the env gene is the viral spike protein, which has two main parts: the surface protein (SU) and the transmembrane protein (TM). (wikipedia.org)
  • External envelope protein of the human immunodeficiency virus which is encoded by the HIV env gene. (lookformedical.com)
  • Transmembrane envelope protein of the HUMAN IMMUNODEFICIENCY VIRUS which is encoded by the HIV env gene. (lookformedical.com)
  • The biological function of the differentially expressed circRNAs was determined by protein interaction network, Gene Ontology (GO), and Kyoto Encyclopedia of Gene and Genome (KEGG) pathway enrichment. (biomedcentral.com)
  • However, it is not clear whether they are involved in foot-and-mouth disease virus (FMDV) infection and host response. (biomedcentral.com)
  • Although studies have demonstrated that circRNAs are involved in the regulation of host cells after viral infection, there is a lot to unravel to understand the role that circRNAs play in virus-host interactions and viral pathogenesis. (biomedcentral.com)
  • Layers of protein which surround the capsid in animal viruses with tubular nucleocapsids. (lookformedical.com)
  • Exposed on the surface of the viral envelope, the glycoprotein gp120 binds to the CD4 receptor on any target cell that has such a receptor, particularly the helper T-cell. (wikipedia.org)
  • Gp120 has been shown to interfere with the normal function of CD4 and is at least partly responsible for the cytopathic effect of HIV . (lookformedical.com)
  • They are usually synthesized as protein precursors (POLYPROTEINS) and later cleaved into the final viral envelope glycoproteins by a viral protease. (lookformedical.com)
  • As novel regulatory molecules, circRNAs mediate the regulation of viral infections and the cellular immune response, which provide a new perspective for understanding virus-cell interactions. (biomedcentral.com)
  • Species of the genus LENTIVIRUS, subgenus primate immunodeficiency viruses (IMMUNODEFICIENCY VIRUSES, PRIMATE), that induces acquired immunodeficiency syndrome in monkeys and apes (SAIDS). (lookformedical.com)
  • The tropism of the virus is determined by the SU protein domain because it is responsible for the receptor-binding function of the virus. (wikipedia.org)
  • The Env protein of Human Immunodeficiency Virus (HIV) also has a trimeric structure of heterodimers. (wikipedia.org)
  • Without proper folding, protein transport and function can be severely compromised. (wikipedia.org)
  • The products are usually synthesized as protein precursors or POLYPROTEINS, which are then cleaved by viral proteases to yield the final products. (lookformedical.com)
  • The fusion peptide inserts itself in the host cell membrane and brings the host cell membrane very close to the viral membrane to facilitate membrane fusion. (wikipedia.org)
  • Antibodies that reduce or abolish some biological activity of a soluble antigen or infectious agent, usually a virus. (lookformedical.com)
  • Viruses can also use circRNAs to interfere with the host antiviral immune response and help to escape immune surveillance and antiviral immunity. (biomedcentral.com)
  • However, while the late stages of the retrovirus life cycle, consisting of virus replication and egress, have been partly unraveled, the early steps remain largely enigmatic. (biomedcentral.com)
  • In today's study, we looked into the immunological function of Kupffer cells/macrophages in CCl4-induced hepatitis in mice. (enmd-2076.com)
  • The SU domain therefore determines the specificity of the virus for a single receptor molecule. (wikipedia.org)
  • The Env proteins of the Avian Sarcoma and Leukosis virus (ASLV) and the Murine Leukemia Virus (MLV) are both trimers of SU-TM heterodimers. (wikipedia.org)
  • Additional retroviruses, such as Moloney murine leukemia virus (MoMLV), LP-BM5 leukemia virus (MLV), Rous-Sarcoma virus (RSV), avian myeloblastosis virus (AMV), and avian sarcoma/leukosis virus (ASLV) have all recently undergone proteomic analysis and have shown similarities to human afflictions. (medscape.com)
  • To monitor the recovery of HIV-1 from patient plasma, samples are spiked with an internal virion standard, consisting of the replication-competent avian sarcoma)-leukosis retroviral vector RCAS BP(A) (RCAS), derived from an unrelated retrovirus based on Rous sarcoma virus (RSV). (abt-888.net)
  • Although most global proteomics analyses to date have been performed on the human retroviruses HIV and HTLV, the integration of viral DNA into a host genome is the hallmark of this family of viruses. (medscape.com)
  • The need to understand these and other aspects of retroviruses has become more urgent with the dis- covery that AIDS is caused by a retrovirus, the hu- man immunodeficiency virus (HIV). (nih.gov)
  • Although we continue to perform most of these studies with avian and murine retroviruses, we are giving increasing attention to HIV. (nih.gov)
  • The remarkable specificity of virus-host interactions has been known for over twenty years from studies of the polymorphic envelope proteins of avian retroviruses, yet little biochemical information is available about the receptors or about the nature of their interactions with viral envelope glycoproteins. (nih.gov)
  • Paul Bates, John Young, and Suzanne Ortiz are attempting to clone the chicken genes that encode the receptors for multiple subgroups of avian retroviruses. (nih.gov)
  • After viral DNA is synthesized by reverse transcriptase, it is efficiently inserted into chromosomes by a small viral protein, integrase, that performs a recombination reac- tion required for transposition of many types of elements. (nih.gov)
  • Background: The 2009 pandemic H1N1 influenza A virus (pdm09) continue to evolve, and few studies have systemically analyzed the evolution, replication, and transmission of pmd09 viruses in China. (bvsalud.org)
  • Methods: To better understand the evolution and pathogenicity of pdm09 viruses, we systematically analyzed viruses that were confirmed in 2009-2020 in China and characterized their replication and transmission ability. (bvsalud.org)
  • AB - The pneumotropism of Sendai virus in mice was studied in relation to the activation and replication of the virus in the lung. (nih.gov)
  • When trypsin treatment was made which cleaved F into F(1) and F(2) subunits, the virus became activated so that it could initiate replication in the bronchial epithelium of the lung. (nih.gov)
  • In this case, the progeny virus was produced in the activated form and multiple-cycle replication occurred successively. (nih.gov)
  • A parallel relationship was found between the degree of the viral replication and that of clinical signs of the respiratory disease, body weight loss, and histopathological changes in the lung. (nih.gov)
  • A protease mutant, TR-2, which was able to be activated only by chymotrypsin but not by trypsin, could also initiate replication in the bronchial epithelium, when activated by chymotrypsin before inoculation into mice. (nih.gov)
  • The progeny virus, however, remained inactive, and the replication was limited to a single cycle, which resulted in the limited lung lesion. (nih.gov)
  • Throughout contamination an extraordinarily large number of viral replication cycles occurs, and this high replicative capacity of HIV-1 prospects to both varied genetic pools and high viral loads (2, 8). (abt-888.net)
  • Viremia could arise either from activation of virus expression from latently infected cell reservoirs or from ongoing cycles of viral replication, for example, in a sanctuary site where there is usually suboptimal drug penetration (1, 6, 31). (abt-888.net)
  • A few of the co-transformed colonies were found to be infectable by avian retrovirus vectors (subgroup A) carrying another selectable marker. (nih.gov)
  • we have recently cloned avian genes encoding receptors for a subgroup of Rous sar- coma virus (RSV) and shown that the receptors resemble the receptor for low-density lipoproteins (LDL). (nih.gov)
  • The Env protein of Human Immunodeficiency Virus (HIV) also has a trimeric structure of heterodimers. (wikipedia.org)
  • More sensitive assays for individual immunodeficiency virus type 1 (HIV-1) RNA are had a need to detect, quantify, and characterize persistent viremia in sufferers who are receiving antiretroviral therapy and whose plasma HIV-1 RNA amounts are suppressed to significantly less than 50 to 75 copies/ml. repeatedly tests a low-copy-number panel that contains 200 to 0.781 copies of HIV-1 RNA per ml of plasma. (abt-888.net)
  • Untreated human immunodeficiency virus type 1 (HIV-1) contamination is characterized by an early acute phase with high levels of viremia that leads to a clinically asymptomatic phase of variable duration, followed by immunodeficiency (15, 23). (abt-888.net)
  • Env is a viral gene that encodes the protein forming the viral envelope. (wikipedia.org)
  • The SU domain therefore determines the specificity of the virus for a single receptor molecule. (wikipedia.org)
  • and 5) the regulation of viral gene expression displays many features characteristic of cellular genes and some thus far unique to viruses. (nih.gov)
  • The results suggest two mechanisms by which ts 1 survivors exhibit resistance to CVB3(m) induction of myocarditis, namely, the rapid production of high-titered anti-CVB3(m) neutralizing antibody in response to CVB3(m) inoculation and altered cell-mediated immune responses against CVB3(m) induced viral or novel cellular antigens. (nih.gov)
  • General, these total results indicate that P10 acts as a significant effector in virus interactions. (researchensemble.com)
  • The tropism of the virus is determined by the SU protein domain because it is responsible for the receptor-binding function of the virus. (wikipedia.org)
  • Exposed on the surface of the viral envelope, the glycoprotein gp120 binds to the CD4 receptor on any target cell that has such a receptor, particularly the helper T-cell. (wikipedia.org)
  • Recently, the receptor for ecotropic murine leukemia virus (MLV) was shown to be a very different type of protein, with about fourteen transmembrane domains. (nih.gov)
  • The mature product of the env gene is the viral spike protein, which has two main parts: the surface protein (SU) and the transmembrane protein (TM). (wikipedia.org)
  • The fusion peptide inserts itself in the host cell membrane and brings the host cell membrane very close to the viral membrane to facilitate membrane fusion. (wikipedia.org)
  • The env gene codes for the gp160 protein which forms a homotrimer, and is cleaved into gp120 and gp41 by the host cell protease, furin. (wikipedia.org)
  • Chicken DNA was introduced into monkey cells (presumed to lack avian 250 virus receptors) by co-transformation with a selectable marker. (nih.gov)
  • Inactive Sendai virus grown in LLC-MK(2) cells, which possessed an uncleaved precursor glycoprotein, F, and was noninfectious to tissue culture cells, neither grew nor caused pathological changes in the lung of mice. (nih.gov)
  • The arrangement of these heterodimers determines the 3D structure of the knobbed spike on the viral surface. (wikipedia.org)
  • The overall results suggest that some activating mechanism for the progeny virus of wild-type Sendai virus exists in the lung of mice and the principle (activator) responsible for this phenomenon has a character similar to trypsin. (nih.gov)
  • Multiple isolates of viruses or transposable elements are considered distinct if at least one promoter region fails to fulfill the above similarity criterion. (expasy.org)
  • At the other end of the spectrum, MMTV (Mouse Mammary Tumor Virus has only 4 sites for oligosaccharide addition (two on gp52 and two on gp37). (wikipedia.org)
  • Note that the expression "active in" does not always refer to the source organism of the promoter (e.g. in viruses). (expasy.org)
  • Virus was not detected in heart tissues of adolescent ts 1 survivors, but inoculation of these mice with CVB3(m) resulted in virus concentrations similar in titers to those found in CVB3(m)-inoculated normal adolescent mice. (nih.gov)
  • PMID- 6299951 TI - Pneumotropism of Sendai virus in relation to protease-mediated activation in mouse lungs. (nih.gov)