Complement C4, Human Complement C4, Human, CAS 80295-48-3,is a native glycoprotein composed of three non-identical subunits of 93, 75, and 32 kDa linked by disulfide bonds.
Complement C4 from human serum has been used in mannose binding lectin (MBL) complex assay of serum samples and in MBL-associated serine proteases based C4 activation assay of plasma samples.
General Description
Complement C4 is mapped to human chromosome 6p21.33. It exists in two isoforms as c4A and c4B. C4 is a 200 kDa protein belonging to α2 macroglobulin (α2M) family. It undergoes posttranslational modification like sulfation and glycosylation and finally proteolysis to become a mature protein.
Biochem/physiol Actions
Variation in the copy number of the complement C4 gene alters the complement c4A and c4B levels in age-related macular degeneration (AMD) and increases risk of developing schizophrenia.
