May be responsible for anchoring smooth muscle cells to elastic fibers, and may be involved not only in the formation of the elastic fiber, but also in the processes that regulate vessel assembly. Has cell adhesive capacity (By similarity). May have a function in placenta formation and initial organogenesis and a later role in interstitial connective tissue. Homotrimer associated through a moderately stable interaction of the C-terminal globular C1q domains, allowing the nucleation of the triple helix and then a further quaternary assembly to higher-order polymers via intermolecular disulfide bonds. Interacts with EMILIN2 (By similarity). Interacts with EFEMP2; this interaction promotes the incorporation of EFEMP2 into the extracellular matrix (PubMed:28717224). Found mainly at the interface between amorphous elastin and microfibrils. Detectable in morula and blastocyst. First expressed in ectoplacental cone in embryos of 6.5 days and in extraembryonic visceral endoderm at 7.5 days. Expressed also in the allantois. Expression in the ectoplacental cone-derived secondary trophoblast giant cells and spongiotrophoblast is strong up to 11.5 days and then declines. In the embryo, high levels are initially expressed in blood vessels, perineural mesenchyme and somites at 8.5 days. Later on, intense expression is identified in the mesenchymal component of organs anlage (ie lung and liver) and different mesenchymal condensations (ie limb bud and branchial arches). At late gestation expression is widely distributed in interstitial connective tissue and smooth muscle cell-rich tissues.