[C1q component of complement and collagen reaction with nucleic acids and polyanions]

Interaction of acid-soluble collagen and C1a component of complement with nucleic acids (NA) is defined by their polyanionic properties. Occurrence of the exocyclic amino group in the structure of nitrous bases from which polynucleotides are made up inhibits their interaction with the proteins are made up inhibits their interaction with the proteins even when this group is within the double helix. This takes place during the formation of the hybrid molecule poly I-poly C. It is assumed that the collagen-like part of C1q greatly contributes to its interaction with nucleic acids.