Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

The architecture of complement component C9 and poly(C9).

R G DiScipio, T E Hugli

    The Journal of Biological Chemistry
    |November 25, 1985
    PubMed
    Summary
    This summary is machine-generated.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Eosinophil cationic protein damages protoscoleces in vitro and is present in the hydatid cyst.

    Parasite immunology·2006
    Same author

    Examination of several potential mechanisms for the negative outcome in a clinical stroke trial of enlimomab, a murine anti-human intercellular adhesion molecule-1 antibody: a bedside-to-bench study.

    Stroke·2001
    Same author

    Mechanisms for cell activation and its consequences for biorheology and microcirculation: Multi-organ failure in shock.

    Biorheology·2001
    Same author

    Pancreatic enzymes and microvascular cell activation in multiorgan failure.

    Microcirculation (New York, N.Y. : 1994)·2001
    Same author

    Intratracheal administration of anaphylatoxin C5a potentiates antigen-induced pulmonary reactions through the prolonged production of cysteinyl-leukotrienes.

    Immunopharmacology·2000
    Same author

    Plasma activation during splanchnic arterial occlusion shock.

    Shock (Augusta, Ga.)·2000
    Same journal

    Isotope-Edited ESEEM: A New Method for Probing Copper Binding Sites in Neurodegenerative Proteins.

    The Journal of biological chemistry·2026
    Same journal

    Introduction to the Thematic Review Series on Intracellular Protein Degradation. The ubiquitous biology of intracellular protein degradation: a tribute to Alfred L. ("Fred") Goldberg.

    The Journal of biological chemistry·2026
    Same journal

    Correction: Aromatic residue-rich amino-terminal segments of temporin L self-assemble into collagen-mimetic peptides with cell-adhesion properties.

    The Journal of biological chemistry·2026
    Same journal

    YhbO is a DJ-1 family glyoxalase and α-oxoaldehyde hydratase that confers resistance to reactive carbonyl stress (112).

    The Journal of biological chemistry·2026
    Same journal

    ARMH3 acts as a central scaffold at the Golgi/TGN through interactions with Arl5, GBF1, and PI4KB.

    The Journal of biological chemistry·2026
    Same journal

    PAX8 controls proximal tubule epithelial identity and stress response through epigenetic modification of distal regulatory elements.

    The Journal of biological chemistry·2026
    See all related articles

    Human complement component C9 polymerizes into tubular structures. This polymerization, involving both C9a and C9b fragments, confers resistance to denaturation and reveals structural insights into complement activation.

    Area of Science:

    • Biochemistry
    • Immunology
    • Structural Biology

    Background:

    • Human complement component C9 (C9) is a key protein in the terminal pathway of the complement system.
    • Understanding C9 architecture is crucial for elucidating its role in immune responses and membrane attack complex formation.

    Purpose of the Study:

    • To investigate the three-dimensional structure of monomeric C9 and its polymerized form, poly(C9).
    • To determine the contribution of different C9 fragments (C9a and C9b) to the stability and structure of poly(C9).

    Main Methods:

    • Transmission electron microscopy (TEM) was used to visualize the architecture of C9 and poly(C9).
    • Alpha-thrombin cleavage was employed to generate C9a and C9b fragments.
    • Immunoelectron microscopy mapped polypeptide regions on poly(C9).

    Related Experiment Videos

  • Concanavalin A-gold labeling visualized oligosaccharide locations.

    • Main Results:

    • Monomeric C9 is ellipsoid; it spontaneously polymerizes into hollow tubules (poly(C9)) with specific dimensions.
    • Poly(C9) exhibits a torus structure formed by radial polypeptide strands, with subunits tilted relative to the axis.
    • Cleavage into C9a and C9b fragments, when polymerized, yields sodium dodecyl sulfate-resistant poly(C9), indicating collective stability.
    • C9a and C9b regions are distributed across the torus, base, and midsection of poly(C9), not clearly segregated.
    • Oligosaccharides are located on the periphery of the torus and base.

    Conclusions:

    • C9 appears to be a single-domain protein that undergoes significant rearrangement upon polymerization.
    • The stability of poly(C9) against denaturation is a collective property of both C9a and C9b polypeptide segments.
    • Polymerization involves major folding of the C9 polypeptide chain parallel to the tubule axis.