ADAMTSL-6 Is a Novel Extracellular Matrix Protein That Binds to Fibrillin-1 and Promotes Fibrillin-1 Fibril Formation

Abstract

ADAMTS (A disintegrin and metalloproteinase with thrombospondin motifs)-like (ADAMTSL) proteins, a subgroup of the ADAMTS superfamily, share several domains with ADAMTS proteinases, including thrombospondin type I repeats, a cysteine-rich domain, and an ADAMTS spacer, but lack a catalytic domain. We identified two new members of ADAMTSL proteins, ADAMTSL-6␣ and -6␤, that differ in their N-terminal amino acid sequences but have common C-terminal regions. When transfected into MG63 osteosarcoma cells, both isoforms were secreted and deposited into pericellular matrices, although ADAMTSL-6␣, in contrast to -6␤, was barely detectable in the conditioned medium. Immunolabeling at the light and electron microscopic levels showed their close association with fibrillin-1-rich microfibrils in elastic connective tissues. Surface plasmon resonance analyses demonstrated that ADAMTSL-6␤ binds to the N-terminal half of fibrillin-1 with a dissociation constant of ϳ80 nM. When MG63 cells were transfected or exogenously supplemented with ADAMTSL-6, fibrillin-1 matrix assembly was promoted in the early but not the late stage of the assembly process. Furthermore, ADAMTSL-6 transgenic mice exhibited excessive fibrillin-1 fibril formation in tissues where ADAMTSL-6 was overexpressed. All together, these results indicated that ADAMTSL-6 is a novel microfibril-associated protein that binds directly to fibrillin-1 and promotes fibrillin-1 matrix assembly.

ADAMTSL6β Protein Rescues Fibrillin-1 Microfibril Disorder in a Marfan Syndrome Mouse Model through the Promotion of Fibrillin-1 Assembly

“…These proteins are localized in connective tissues, including the skin, aorta, and perichondrocytes. Among the ADAMTSL6 family, ADAMTSL6␤ has been shown to associate with fibrillin-1 microfibrils through its direct interaction with the N-terminal region of fibrillin-1 and thereby promotes fibrillin-1 matrix assembly in vitro and in vivo (17). These findings suggest a potential clinical application of ADAMTSL6␤ as a novel MFS therapy by promoting fibrillin-1 microfibril assembly and regulating TGF-␤ activation.…”

“…Expression and Purification of Recombinant Adamtsl6␤-The expression and purification of recombinant Adamtsl6␤ was performed using 293F cells (Invitrogen) and nickel-agarose (Qiagen, Hilden, Germany) as described previously (17). Briefly, pSecTag2A containing an Adamtsl6␤ segment fused with Myc and His tags at its C terminus was transfected into 293F cells, which were cultured for 3 days.…”

ADAMTS10 Protein Interacts with Fibrillin-1 and Promotes Its Deposition in Extracellular Matrix of Cultured Fibroblasts

“…Furthermore, ADAMTSL4 mutations occur in recessively inherited isolated ectopia lentis (31,32), and ADAMTS17 mutations result in ectopia lentis in dogs (33) and a WMS-like syndrome in humans (15). Recently, it was shown that ADAMTSL6 was capable of enhancing fibrillin-1 assembly into ECM (34).…”

Trends in Periodontal Regeneration Therapy: Potential Therapeutic Strategy of Extracellular Matrix Administration for Periodontal Ligament Regeneration

“…These proteins are localized in connective tissues, including the skin, aorta and perichondrocytes. Among ADAMTSL6, ADAMTSL6β has shown to associated with fibrillin-1 microfibrils through its direct interaction with the N-terminal region of fibrillin-1 and promotes fibrillin-1 matrix assembly in vitro and in vivo [43]. These findings suggest a potential clinical application of ADAMTSL6β as a novel MFS therapy by promoting fibrillin-1 microfibril assembly and regulating TGF-β activation.…”