Human complement factor H: two factor H proteins are derived from alternatively spliced transcripts.
The human complement factor H is an important component in the control of the alternative pathway of complement activation. We have previously shown that a least three factor H homologous mRNA species of 4.3 kb, 1.8 kb and 1.4 kb in length are constitutively expressed in human liver. In addition, several factor H-related proteins have been detected in human sera using antibodies directed against the classical human factor H glycoprotein of 150 kDa. The structure of the additional polypeptides has not been shown so far. Circumstantial evidence suggests that the 1.8-kb mRNA might encode the 43-kDa factor H-like polypeptide. Here we report the isolation, characterization and eukaryotic expression of the first full-length cDNA representing the major 4.3-kb mRNA and the 1.8-kb mRNA of human factor H. We show that the 4.3-kb transcript encodes the 150-kDa-factor H glycoprotein and the 1.8-kb mRNA the 43-kDa factor H polypeptide. The identity of the two cDNA in a region of 1400 nucleotides suggests that the two factor H-related transcripts are derived from one gene by a process of alternative splicing.
Estaller
C
C
Institut für Immunologie, München, FRG.
Schwaeble
W
W
Dierich
M
M
Weiss
E H
EH
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D003180:Complement C3b Inactivator Proteins / Q000235:genetics*; D017242:Complement Factor H; D004247:DNA / Q000235:genetics; D015870:Gene Expression; D005796:Genes; D005822:Genetic Vectors; D006801:Humans; D008969:Molecular Sequence Data; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics; D015183:Restriction Mapping; D014162:Transfection
C493495:CFH protein, human; D003180:Complement C3b Inactivator Proteins; D012333:RNA, Messenger; D017242:Complement Factor H; D004247:DNA