The quaternary structure in solution of human complement subcomponent C1r2C1s2.

摘要: C1r2C1s2 is a subcomponent of first component C1 the complement cascade. Previously two distinct models for its structure have been described, in which either linear rod-like assembly globular domains found each C1s and C1r, or these are arranged to form an asymmetric X-shaped structure. These were evaluated by using hydrodynamic simulations neutron scattering. The data on C1s, C1s2 C1r readily represented straight cylinders, but not C1r2 C1r2C1s2. Tests X-structure successfully predicted experimental sedimentation coefficients, thus supporting this model. Neutron scattering analyses consistent with C1r2. An was give good account at large angles. total length monomers determined as 17-20 nm, compatible electron microscopy. On basis known sequences accounted arrangement serine-proteinase domain (length 4 nm), short consensus repeat (2 x entity containing I, II III (4-7 nm).