Kohei Miyazono

Transforming Growth Factor-β Receptors and Signal Transduction

The transforming growth factor-β (TGF-β) superfamily consists of multifunctional proteins that include TGF-βs, activins, inhibins, and bone morphogenetic proteins (BMPs), which regulate growth, differentiation, metabolism, and apoptosis of various cell types (1,2). Members of the TGF-β superfamily transduce signals via heteromeric complexes of two different serine/threonine kinase receptors, denoted type I and type II. Both type I and type II receptors are required for signal transduction (3).

Regulation of Angiogenesis by TGF- β Superfamily

The angiogenesis process is regulated by many growth factors and cytokines, including transforming growth factor-beta (TGF-β) (1–3). The TGF-β superfamily, which contains the TGF-β family, the activin family, and the bone morphogenetic protein (BMP) family (4), exerts various effects on vascular cells. The effects of TGF-β differ between in vitro and in vivo (1–3). In this study, to investigate the mechanisms of regulation of angiogenesis by TGF-β superfamily members, angiogenic activity in vivo and the effects on cultured endothelial cells in vitro of TGF-β 1 activin A, and BMP-2 were examined.