标题:Identification of a distinct type IV collagen alpha chain with restricted kidney distribution and assignment of its gene to the locus of X chromosome-linked Alport syndrome.
期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1990
卷号:87
期号:4
页码:1606-1610
DOI:10.1073/pnas.87.4.1606
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We have identified and extensively characterized a type IV collagen alpha chain, referred to as alpha 5(IV). Four overlapping cDNA clones isolated contain an open reading frame for 543 amino acid residues of the carboxyl-terminal end of a collagenous domain, a 229-residue carboxyl-terminal noncollagenous domain, and 1201 base pairs coding for a 3' untranslated region. The collagenous Gly-Xaa-Yaa repeat sequence has five imperfections that coincide with those in the corresponding region of the alpha 1(IV) chain. The noncollagenous domain has 12 conserved cysteine residues and 83% and 63% sequence identity with the noncollagenous domains of the alpha 1(IV) and alpha 2(IV) chains, respectively. The alpha 5(IV) chain has less sequence identity with the putative bovine alpha 3(IV) and alpha 4(IV) chains. Antiserum against an alpha 5(IV) synthetic peptide stained a polypeptide chain of about 185 kDa by immunoblot analysis and immunolocalization of the chain in human kidney was almost completely restricted to the glomerulus. The gene was assigned to the Xq22 locus by somatic cell hybrids and in situ hybridization. This may be identical or close to the locus of the X chromosome-linked Alport syndrome that is believed to be a type IV collagen disease.