Related Experiment Video
Updated: Jul 14, 2026
09:39
Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein
Published on: April 21, 2015
Interferon-induced Mx proteins in antiviral host defense.
Otto Haller1, Peter Staeheli, Georg Kochs
1Abteilung Virologie, Institut für Medizinische Mikrobiologie und Hygiene, Universität Freiburg, D-79008 Freiburg, Germany. otto.haller@uniklinik-freiburg.de
Biochimie
|June 16, 2007
Summary
Mx proteins, a type of guanosine triphosphatase (GTPase), provide antiviral defense by trapping viral components. These proteins inhibit RNA viruses like influenza by interfering with early life cycle stages.
Area of Science:
- Molecular Biology
- Virology
- Cell Biology
Background:
- Mx proteins are dynamin-like guanosine triphosphatases (GTPases) crucial for the interferon-induced antiviral state.
- They exhibit self-assembly and membrane association, similar to dynamin.
- A key feature is their broad-spectrum antiviral activity against RNA viruses.
Purpose of the Study:
- To elucidate the mechanism of antiviral activity of Mx GTPases against RNA viruses.
- To understand the role of Mx proteins in inhibiting viral replication at early stages.
- To investigate the specific interactions and cellular localization of mouse Mx1 and human MxA GTPases.
Main Methods:
- Localization studies of mouse Mx1 and human MxA GTPases within host cells.
- Analysis of interactions between Mx GTPases and viral components (nucleoproteins).
- Investigation of the role of GTP-binding and effector functions in antiviral activity.
Main Results:
- Mouse Mx1 GTPase localizes to the nucleus, inhibiting nuclear-replicating viruses like influenza.
- Human MxA GTPase localizes to the cytoplasm and endoplasmic reticulum, interfering with bunyavirus and Thogoto virus replication.
- MxA recognizes viral nucleocapsid proteins, disrupting viral genome replication and nucleocapsid transport.
Conclusions:
- Mx GTPases detect viral infection by sensing nucleocapsid-like structures.
- They trap viral components, preventing new virus particle formation.
- GTP-binding and effector functions are essential for Mx GTPase antiviral activity.
Related Concept Videos
01:30Inhibitors of Viral Protein Synthesis
Protein synthesis is indispensable for viral replication, as viruses lack the cellular machinery required for this process and must hijack the host's translational apparatus. In response, host cells deploy a critical innate immune defense involving interferons, specialized cytokines that play a central role in inhibiting viral propagation.Upon viral detection, infected cells release interferons that bind to receptors on adjacent uninfected cells, activating the JAK-STAT signaling pathway and...
01:29Immune Response Against Viral Pathogens
The immune system's response to viral infections is a complex and coordinated process involving natural killer (NK) cells, T cell-mediated responses, and antibody-mediated responses.
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
01:23Antimicrobial Proteins
Antimicrobial proteins are important components of the immune system. They aid the body in combating pathogens by either killing them directly or hindering their replication processes. Four main types of antimicrobial substances are interferons, the complement system, iron-binding proteins, and antimicrobial proteins.
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
01:19Inhibitors of Virion Maturation and Assembly
As part of their replication cycle, certain viruses synthesize long precursor proteins called polyproteins within infected host cells. In human immunodeficiency virus (HIV), two major polyproteins are produced: Gag and Gag-Pol. The Gag polyprotein supplies the structural components of the virus, while Gag-Pol includes essential viral enzymes such as reverse transcriptase, integrase, and protease. After synthesis, these polyproteins move to the host cell membrane, where they assemble into an...
01:25Inhibitors Of Virion Release
Viral replication and dissemination rely on efficient mechanisms for host cell entry, genome replication, assembly, and release. Influenza viruses, such as types A and B, are negative-sense single-stranded RNA viruses with a segmented genome, that depend on two critical surface glycoproteins to carry out these processes: hemagglutinin (HA) and neuraminidase (NA). HA initiates infection by binding to sialic acid residues on the surface of host epithelial cells, facilitating receptor-mediated...
01:26Antigens Involved in Adaptive Immunity
An antigen is any substance the immune system identifies as foreign and potentially harmful to the body, prompting an immune response. Antigens have two functional properties: immunogenicity and reactivity. Immunogenicity is the ability of an antigen to stimulate a specific immune response. At the same time, reactivity describes the antigen's ability to react with the cells and antibodies produced in response to it.
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.