This family consists of several eukaryotic BMP and activin membrane-bound inhibitor (BAMBI) proteins. Members of the transforming growth factor-beta (TGF-beta) superfamily, including TGF-beta, bone morphogenetic proteins (BMPs), activins and nodals, are vital for regulating growth and differentiation. BAMBI is related to TGF-beta-family type I receptors but lacks an intracellular kinase domain. BAMBI is co-expressed with the ventralising morphogen BMP4 during Xenopus embryogenesis and requires BMP signalling for its expression. The protein stably associates with TGF-beta-family receptors and inhibits BMP and activin as well as TGF-beta signalling [1].

1: Silencing of TGF-beta signalling by the pseudoreceptor BAMBI. Onichtchouk D, Chen YG, Dosch R, Gawantka V, Delius H, Massague J, Niehrs C; Nature 1999;401:480-485. PMID:10519551