Recent developments in the cell biology of basic fibroblast growth factor (bFGF) have been reviewed, focusing on its structure, synthesis, distribution, biological activities, and interactions with receptors and the extracellular matrix. bFGF was first identified in pituitary and brain extracts, and its structure was characterized as a 146-amino acid protein with a molecular weight of 16,400 in bovine pituitary. It has a basic isoelectric point and exhibits heparin-binding properties. bFGF is a member of the fibroblast growth factor (FGF) family, which includes aFGF, hst/K-fgf, FGF-5, and int-2. These proteins share some structural and functional similarities but also have distinct characteristics. The synthesis of bFGF involves a unique mechanism, with multiple forms of the protein being produced through different translation initiation sites. bFGF is primarily synthesized in the cytoplasm and can be secreted, but its release mechanism is not fully understood. bFGF has been found in various tissues and cells, and its distribution is influenced by factors such as cell type and environment. It plays a role in cell proliferation, migration, and angiogenesis, and is involved in embryonic development and wound healing. Receptors for bFGF have been identified on various cell types, and bFGF can compete with aFGF for receptor binding, suggesting shared receptors. bFGF interacts with heparin and heparan sulfate proteoglycans (HSPG), which may influence its stability and function. The interaction of bFGF with the extracellular matrix is important for its biological activity, as it can be released from the matrix by enzymes such as heparinase and plasmin. bFGF has transforming potential, but its role in tumor development is not fully understood. The expression of bFGF can be influenced by various factors, and its function may differ depending on the cell type and environment. The lack of a signal sequence in bFGF suggests that it may act intracellularly or in a unique manner compared to other growth factors. The presence of multiple forms of bFGF, generated through different translation initiation sites, indicates that they may have distinct functional roles. In conclusion, bFGF is a complex protein with diverse biological functions, and its interactions with the extracellular matrix and receptors are crucial for its activity. Further research is needed to fully understand its role in various biological processes and its potential therapeutic applications.Recent developments in the cell biology of basic fibroblast growth factor (bFGF) have been reviewed, focusing on its structure, synthesis, distribution, biological activities, and interactions with receptors and the extracellular matrix. bFGF was first identified in pituitary and brain extracts, and its structure was characterized as a 146-amino acid protein with a molecular weight of 16,400 in bovine pituitary. It has a basic isoelectric point and exhibits heparin-binding properties. bFGF is a member of the fibroblast growth factor (FGF) family, which includes aFGF, hst/K-fgf, FGF-5, and int-2. These proteins share some structural and functional similarities but also have distinct characteristics. The synthesis of bFGF involves a unique mechanism, with multiple forms of the protein being produced through different translation initiation sites. bFGF is primarily synthesized in the cytoplasm and can be secreted, but its release mechanism is not fully understood. bFGF has been found in various tissues and cells, and its distribution is influenced by factors such as cell type and environment. It plays a role in cell proliferation, migration, and angiogenesis, and is involved in embryonic development and wound healing. Receptors for bFGF have been identified on various cell types, and bFGF can compete with aFGF for receptor binding, suggesting shared receptors. bFGF interacts with heparin and heparan sulfate proteoglycans (HSPG), which may influence its stability and function. The interaction of bFGF with the extracellular matrix is important for its biological activity, as it can be released from the matrix by enzymes such as heparinase and plasmin. bFGF has transforming potential, but its role in tumor development is not fully understood. The expression of bFGF can be influenced by various factors, and its function may differ depending on the cell type and environment. The lack of a signal sequence in bFGF suggests that it may act intracellularly or in a unique manner compared to other growth factors. The presence of multiple forms of bFGF, generated through different translation initiation sites, indicates that they may have distinct functional roles. In conclusion, bFGF is a complex protein with diverse biological functions, and its interactions with the extracellular matrix and receptors are crucial for its activity. Further research is needed to fully understand its role in various biological processes and its potential therapeutic applications.