Figure 1.

Schematic diagram of the plasmids encoding basic fibroblast growth factor (PL-bFGF), platelet-derived growth factor (PL-PDGF), and bFGF and PDGF (PL-F-P). Two transcription units allowing the combined expression of two genes were first assembled into a single vector. bFGF and PDGF-BB (PDGF homodimer) genes were amplified by polymerase chain reaction (PCR). The amplified fragment was digested with restrictive enzyme and inserted into the multigenic vector. SV40, Simian virus 40. MCS, multiple cloning site.