Its binding to fibronectin and some other ligands is calcium dependent. May act as an adapter that mediates the interaction between FBN1 and ELN. Homotrimer; disulfide-linked. Interacts with LAMA2 (PubMed:10022829). Interacts with FBN1 (via N-terminal domain). Forms a ternary complex with ELN and FBN1 (By similarity). Additional isoforms seem to exist. Component of both basement membranes and other connective tissues. The differential expression of the fibulin family contributes to the formation of molecularly distinct extracellular matrices already during early developmental stages of a large number of tissues. Glucocorticoids suppressed mRNA expression and protein synthesis. Belongs to the fibulin family.