Structural component of the 10-12 nm diameter microfibrils of the extracellular matrix, which conveys both structural and regulatory properties to load-bearing connective tissues. Fibrillin-1-containing microfibrils provide long-term force bearing structural support. In tissues such as the lung, blood vessels and skin, microfibrils form the periphery of the elastic fiber, acting as a scaffold for the deposition of elastin. In addition, microfibrils can occur as elastin-independent networks in tissues such as the ciliary zonule, tendon, cornea and glomerulus where they provide tensile strength and have anchoring roles. Fibrillin-1 also plays a key role in tissue homeostasis through specific interactions with growth factors, such as the bone morphogenetic proteins (BMPs), growth and differentiation factors (GDFs) and latent transforming growth factor-beta-binding proteins (LTBPs), cell-surface integrins and other extracellular matrix protein and proteoglycan components. Regulates osteoblast maturation by controlling TGF-beta bioavailability and calibrating TGF-beta and BMP levels, respectively. Negatively regulates osteoclastogenesis by binding and sequestering an osteoclast differentiation and activation factor TNFSF11. This leads to disruption of TNFSF11-induced Ca(2+) signaling and impairment of TNFSF11-mediated nuclear translocation and activation of transcription factor NFATC1 which regulates genes important for osteoclast differentiation and function. Mediates cell adhesion via its binding to cell surface receptors integrins ITGAV:ITGB3 and ITGA5:ITGB1. Binds heparin and this interaction plays an important role in the assembly of microfibrils. Hormone that targets the liver to increase plasma glucose levels. Secreted by white adipose tissue and circulates in the plasma. Acts in response to fasting and promotes blood glucose elevation by binding to the surface of hepatocytes. Promotes hepatocyte glucose release by activating the protein kinase A activity in the liver, resulting in rapid glucose release into the circulation. Interacts with COL16A1. Interacts with integrin alpha-V/beta-3. Interacts with ADAMTS10; this interaction promotes microfibril assembly. Interacts with THSD4; this interaction promotes fibril formation. Interacts (via N-terminal domain) with FBLN2 and FBLN5. Interacts with ELN. Forms a ternary complex with ELN and FBLN2 or FBLN5 and a significant interaction with ELN seen only in the presence of FBLN2 or FBLN5. Interacts (via N-terminal domain) with LTBP2 (via C-terminal domain) in a Ca(+2)-dependent manner. Interacts (via N-terminal domain) with LTBP1 (via C-terminal domain). Interacts with integrins ITGA5:ITGB1, ITGAV:ITGB3 and ITGAV:ITGB6. Interacts (via N-terminal domain) with BMP2, BMP4, BMP7, BMP10 and GDF5. Interacts (via N-terminal domain) with MFAP2 and MFAP5. Interacts with ADAMTSL5. Interacts with MFAP4. Interacts (via N-terminal domain) with TNFSF11 in a Ca(+2)-dependent manner. Interacts (via N-terminal domain) with EFEMP2; this interaction inhibits EFEMP2 binding to LOX and ELN (By similarity). Fibrillin-1 and Asprosin chains are still linked together during the secretion from cells, but are subsequently separated by furin. Secreted into the plasma. Cleavage of N- and C-terminus by furin is required for incorporation into the extracellular matrix and assembly into microfibrils. The C-terminus, which corresponds to the Asprosin chain, was initially thought to constitute a propeptide. Fibrillin-1 and Asprosin chains are still linked together during the secretion from cells, but are subsequently separated by furin, an essential step for incorporation of Fibrillin-1 into the nascent microfibrils. Forms intermolecular disulfide bonds either with other fibrillin-1 molecules or with other components of the microfibrils. O-glycosylated on serine residues by POGLUT2 and POGLUT3 which is necessary for efficient protein secretion. Belongs to the fibrillin family.