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. 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. Interacts with EFEMP2; this interaction promotes the incorporation of EFEMP2 into the extracellular matrix (By similarity). Found mainly at the interface between amorphous elastin and microfibrils. Distributed in tissues where resilience and elastic recoil are prominent. Highest levels in the adult small intestine, aorta, lung, uterus, and appendix and in the fetal spleen, kidney, lung, and heart; intermediate expression was detected in adult liver, ovary, colon, stomach, lymph node and spleen; adult heart, bladder, prostate, adrenal gland, mammary gland, placenta and kidney showed low expression whereas a series of other adult tissues, including skeletal muscle and different regions of adult brain show no expression. Its deposition precedes the appearance of elastin and is simultaneous with that of fibrillin 1.