Description
Twisted gastrulation protein (TSG) is a secreted protein1 that is involved in osteoblast differentiation and mineralization by regulating bone morphogenetic protein (BMP) signaling.2 It also regulates dorsoventral axis formation in early Drosophila and Xenopus development.3 TSG is one of five secreted proteins required to pattern the dorsal part of the early Drosophila embryo.4 TSG bears a weak resemblance to human connective tissue growth factor (CTGF), a TGF-beta-induced protein.5