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Human complement factor B: cDNA cloning, nucleotide sequencing, phenotypic conversion by site-directed mutagenesis and expression.

T Horiuchi·S Kim·M Matsumoto·I Watanabe·S Fujita·J E Volanakis
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Abstract

A full-length cDNA clone, BHL4-1, encoding factor B was isolated from a human liver cDNA library and sequenced in its entirety. It consists of 2388 bp which include a 5'-untranslated region of 40 bp, a single open reading frame, 2292 bp in length, and a 3'-untranslated region of 56 bp followed by a poly-A tail. The deduced amino acid sequence comprises 25 residues of a putative leader peptide and 739 residues of the mature polypeptide chain of the F allele of factor B. We constructed an S allele-like Q7R mutant of BHL4-1 by site-directed mutagenesis. Both the wild-type and mutant factor B cDNA were expressed transiently in a eukaryotic system. The specific hemolytic activities of the two recombinant factor B alleles and of native B were not significantly different from each other.

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AllelesAmino Acid SequenceBase SequenceCell LineCloning, MolecularComplement ActivationComplement C2Complement C3-C5 ConvertasesComplement Factor BDNA, ComplementaryGene ExpressionHumansLiverMolecular Sequence DataMutagenesis, Site-DirectedPhenotypeSequence Analysis, DNAJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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T Horiuchi, S Kim, M Matsumoto, I Watanabe, S Fujita, J E Volanakis. 1993. Human complement factor B: cDNA cloning, nucleotide sequencing, phenotypic conversion by site-directed mutagenesis and expression.. https://doi.org/10.1016/0161-5890(93)90450-p

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