Sequence, recombinant expression and tissue localization of two novel extracellular matrix proteins, fibulin-3 and fibulin-4.

摘要: Abstract Fibulin-1 and fibulin-2 have previously been identified as basement membrane microfibrillar proteins with a broad binding repertoire for other extracellular ligands. Here we report on the cloning sequence analysis of human fibulin-3 (487 residues), also known protein S1–5, fibulin-4 (443 residues). These novel members this family are most closely related to fibulin-1C. They consist C-terminal globular domain III, shared by fibrillins, central rod-like element composed five calcium-binding epidermal growth factor-like (EG) modules (domain II) an N-terminal interrupted EG module I) which replaces anaphylatoxin-like fibulins. This predicted structure was supported electron microscopy fibulin-4, demonstrated short rods. Northern blots showed that both fibulins expressed in several tissues variable extent they up-regulated quiescent fibroblasts. Specific antibodies were raised against each did not cross-react fibulin-1. Immunohistology adult mouse fibulin-3, fibulin-1 overlapping but distinct tissue localizations. A particularly prominent feature staining sets large small blood vessels.