Transforming growth factor-beta, or TGFB (see TGFB1; MIM 190180), remains biologically latent after secretion, blocked from activity by its N-terminal propeptide (the latency-associated peptide, or LAP). TGFB is activated by its dissociation from LAP. The latent form of TGFB is secreted in association with a latent TGFB-binding protein, or LTBP (see LTBP1; MIM 150390), and assembled into the extracellular matrix. LTBPs are mainly composed of epidermal growth factor (EGF; MIM 131530)-like repeats and protein domains with 8-cysteine repeats, both of which are also found in fibrillins (e.g., MIM 134797). See Oklu and Hesketh (2000) [PubMed 11104663] for a review of the LTBP gene family.[supplied by OMIM]
