Expression and processing of biologically active fibroblast growth factors in the yeast Saccharomyces cerevisiae.
Chemically synthesized genes for bovine and human fibroblast growth factors (FGFs) were expressed in heterologous microorganisms. Although the intracellular expression or secretion of acidic and basic FGFs in Escherichia coli or Saccharomyces cerevisiae yielded recombinant growth factors with high biological activity, the resulting proteins had structural microheterogeneity due to modified amino termini. Expression of amino-terminal extended forms of human acidic and basic FGFs in S. cerevisiae gave rise to soluble, but cell-associated polypeptides, with potent biological activity. These yeast-derived proteins were processed in vivo by removal of initiation codon-derived methionine residues and by amino-terminal acetylation. Both of these processes have been observed in mammalian tissues. The yeast systems described here, therefore, provide a good model system for the expression of FGFs as intracellular proteins, but more importantly they give high levels of authentically processed human FGFs with many potential medical applications. Since the recombinant proteins have all the biological activities of their native counterparts, their possible applications in wound healing, tissue grafting, nerve regeneration, and treatment of ischemia are discussed.
Barr
P J
PJ
Chiron Corporation, Emeryville, California 94608.
Cousens
L S
LS
Lee-Ng
C T
CT
Medina-Selby
A
A
Masiarz
F R
FR
Hallewell
R A
RA
Chamberlain
S H
SH
Bradley
J D
JD
Lee
D
D
Steimer
K S
KS
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001681:Biological Assay; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D003315:Cornea / Q000187:drug effects; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics; D005346:Fibroblast Growth Factors / Q000235:genetics* / Q000494:pharmacology; D005796:Genes; D005813:Genes, Synthetic; D006801:Humans; D008969:Molecular Sequence Data; D009389:Neovascularization, Pathologic; D010957:Plasmids; D011817:Rabbits; D011994:Recombinant Proteins / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D014158:Transcription, Genetic
D011994:Recombinant Proteins; D005346:Fibroblast Growth Factors