Structural protein that stabilizes microvessels and muscle cells, both in heart and in skeletal muscle. Restin potently inhibits angiogenesis. Trimer; disulfide-linked. Interacts moderately with EFEMP2. Detected in testis, brain, heart, kidney, skeletal muscle and skin (at protein level). Detected in heart and skeletal muscle. Detected at low levels from day 7 to 11 of embryonic development. Levels are much increased and remain high from day 15 to 17. Prolines at the third position of the tripeptide repeating unit (G-X-Y) are hydroxylated in some or all of the chains. O-glycosylated; contains chondroitin sulfate. Belongs to the multiplexin collagen family. The name Restin has also been used for CAP-Gly domain-containing linker protein 1 the product of the CLIP1 gene.