SEQUENCE AND EXPRESSION OF A NOVEL MEMBER (LTBP-4) OF THE FAMILY OF LATENT TRANSFORMING GROWTH-FACTOR-BETA BINDING-PROTEINS

Overlapping cDNA clones from human heart and melanoma libraries were u sed to establish the 1587-residue sequence of a novel protein (LTBP-4) belonging to the family of extracellular microfibrillar proteins whic h also bind transforming growth factor-beta. LTBP-4 consists of 20 EG modules, 17 of them with a consensus sequence for calcium binding, 4 T B modules with 8 cysteines and several proline-rich regions, Northern blots demonstrated a single 5 kb mRNA which is highly expressed in hea rt but also present in skeletal muscle, pancreas, placenta and lung. T he modular structure predicts that LTBP-4 should be a microfibrillar p rotein,which probably also binds TGF-beta. (C) 1997 Federation of Euro pean Biochemical Societies.