Human basic fibroblast growth factor gene encodes four polypeptides: three initiate translation from non-AUG codons.
Human basic fibroblast growth factor (bFGF) is an angiogenic polypeptide mitogen present in a wide variety of mesoderm- and neuroectoderm-derived tissues. bFGF cDNA and genomic clones predict a 17.8-kDa (155-amino acid) gene product based on the presence of a single putative translational initiator ATG codon. However, a bFGF protein isolated from human placenta contains two additional amino acids NH2-terminal to the predicted initiator methionine. We report here that the human cell line SK-HEP-1 coexpresses four molecular forms (17.8, 22.5, 23.1, and 24.2 kDa) of bFGF. The 17.8-kDa bFGF protein is translationally initiated at the previously predicted methionine (AUG) codon, whereas the 22.5-, 23.1-, and 24.2-kDa proteins initiate at unusual non-AUG codons. The higher molecular weight forms are colinear NH2-terminal extensions of the 18-kDa bFGF.
Florkiewicz
R Z
RZ
Whittier Institute for Diabetes and Endocrinology, La Jolla, CA 92037.
Sommer
A
A
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003062:Codon / Q000235:genetics*; D005260:Female; D005346:Fibroblast Growth Factors / Q000235:genetics*; D005796:Genes; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D010442:Peptide Chain Initiation, Translational; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics*; D014158:Transcription, Genetic; D014162:Transfection
D003062:Codon; D012333:RNA, Messenger; D005346:Fibroblast Growth Factors