than the skin of wild-type mice. DS-epi1−/− collagen fibrils were more heterogeneous in denaturation profiles and in vitro experiments showed that, in DS-epi1−/− skin, decorin was the proteoglycan that was responsible for altered collagen structure (Fig. 4A). Electron microscopy showed that the diameter of DS-epi1−/− fibrils was 85 nm compared to 62 nm for wild-type mice 28. In summary, iduronic acid in the CS/DS chain and particularly of IdoA blocks participates in skin collagen fibril maturation.
