Recovery of mitogenic activity of a growth factor mutant with a nuclear translocation sequence.
Heparin-binding growth factor-1 (HBGF-1) is an angiogenic polypeptide mitogen for mesoderm- and neuroectoderm-derived cells in vitro and remains biologically active after truncation of the amino-terminal domain (HBGF-1 alpha) of the HBGF-1 beta precursor. Polymerase chain reaction mutagenesis and prokaryotic expression systems were used to prepare a mutant of HBGF-1 alpha lacking a putative nuclear translocation sequence (amino acid residues 21 to 27; HBGF-1U). Although HBGF-1U retains its ability to bind to heparin, HBGF-1U fails to induce DNA synthesis and cell proliferation at concentrations sufficient to induce intracellular receptor-mediated tyrosine phosphorylation and c-fos expression. Attachment of the nuclear translocation sequence from yeast histone 2B at the amino terminus of HBGF-1U yields a chimeric polypeptide (HBGF-1U2) with mitogenic activity in vitro and indicates that nuclear translocation is important for this biological response.
Imamura
T
T
Laboratory of Molecular Biology, Jerome H. Holland Laboratory for the Biomedical Sciences, American Red Cross, Rockville, MD 20855.
Engleka
K
K
Zhan
X
X
Tokita
Y
Y
Forough
R
R
Roeder
D
D
Jackson
A
A
Maier
J A
JA
Hla
T
T
Maciag
T
T
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D004261:DNA Replication / Q000187:drug effects; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D016220:Fibroblast Growth Factor 1 / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D007700:Kinetics; D051379:Mice; D008934:Mitogens / Q000494:pharmacology; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D011975:Receptors, Mitogen / Q000378:metabolism; D040262:Receptors, Vascular Endothelial Growth Factor; D011994:Recombinant Proteins / Q000378:metabolism / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
D008934:Mitogens; D015345:Oligonucleotide Probes; D011975:Receptors, Mitogen; D011994:Recombinant Proteins; D016220:Fibroblast Growth Factor 1; D040262:Receptors, Vascular Endothelial Growth Factor