1. Structural organization of the α1(VII) polypeptide of type VII collagen, as deduced by molecular cDNA cloning, and the distribution of COL7A1 mutations identified in dystrophic variants of EB along the polypeptide. The pro α1(VII) chain consist of a triple-helical collagenous domain, which contains imperfections or interruptions in the Gly-X-Y repeat sequence, including a 39-amino acid “hinge” region. Noncollagenous amino-terminal NC1 and C-terminal NC2 segments flank the collagenous domain. The NC1 domain consists of submodules with homology to known adhesive proteins, as indicated at the lower-left corner. The NC2 domain has a segment with homology with the Kunitz protease-inhibitor molecule. The arrows indicate the positions of distinct genetic mutations that have been disclosed in the COL7A1 gene. The mutations depicted above the type VII collagen molecule are primarily nonsense mutations or small insertions or deletions that result in frameshift and premature termination codon of translation. These mutations are characteristically associated with recessively inherited variants of dystrophic EB. The mutations shown below the type VII collagen molecule are glycine substitution mutations affecting the collagenous domain of the molecule. The majority of these mutations cause a dominantly inherited dystrophic EB, as a result of dominant negative interference. However, as indicated in the text, some of the glycine substitution mutations are recessive. (Modified from Uitto.111 Used with permission.)
Source: Epidermolysis Bullosa: The Disease of the Cutaneous Basement Membrane Zone GenBank accession numbers for genes of the cutaneous basement membrane zone (BMZ): LAMA3 (X85108, X85107); LAMC2 (U43327, U311787–U31201); LAMB3 (L25541, U17744–U17760); ITGB4 (X51841, U66529–U66541); ITGA6 (X59512; AF166335–AF166343); COL7A1 (L02870, L23982); PLEC1 (Z54367, U53204, U53834, U63609–U63610); BPAG1 (L11690, M69225); BPAG2 (U76564–U76604); KRT5 (U05838–U05849); KRT5 (NM000526). , The Online Metabolic and Molecular Bases of Inherited Disease
Citation: Valle D, Beaudet AL, Vogelstein B, Kinzler KW, Antonarakis SE, Ballabio A, Gibson K, Mitchell G. The Online Metabolic and Molecular Bases of Inherited Disease; 2014 Available at: Accessed: November 11, 2017
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