Complement C4-B (P01029)

Uniprot ID P01029
Protein Name Complement C4-B
Gene Name C4b
Species Mus musculus (Mouse)
Signal peptide(a) Y Secretome P(b) 0.393
Function Non-enzymatic component of C3 and C5 convertases and thus essential for the propagation of the classical complement pathway. Covalently binds to immunoglobulins and immune complexes and enhances the solubilization of immune aggregates and the clearance of IC through CR1 on erythrocytes. Catalyzes the transacylation of the thioester carbonyl group to form ester bonds with carbohydrate antigens (By similarity). .
GO - Molecular function
  • carbohydrate binding : ISO:MGI
  • complement binding : ISO:MGI
  • complement component C1q binding : ISO:MGI
  • endopeptidase inhibitor activity : IEA:InterPro
GO - Biological process
  • complement activation : IMP:MGI
  • complement activation, classical pathway : IEA:UniProtKB-KW
  • immunoglobulin mediated immune response : IMP:MGI
  • inflammatory response : IEA:UniProtKB-KW
  • innate immune response : IEA:UniProtKB-KW
(a) The Signal peptide D-score cutoff for "YES"(having signal peptide) is 0.45.
(b) Non-classically secreted proteins should obtain an NN-score(Neural Networks score) exceeding the normal threshold of 0.5, but not at the same time be predicted to contain a signal peptide.