Abstract
Alport syndrome (AS) is caused by mutations in type IV collagen α3, α4, and α5 chains. The three chains form a heterotrimer. We have previously shown that all 15 types of recombinant α5(IV) chains with mutations, corresponding to AS mutations, in the noncollagenous (NC1) domain are defective in terms of heterotrimer formation and/or secretion of the heterotrimer from cells. A relatively large family with Cys1638Tyr in the NC1 domain of the α5(IV) chain has been found to have mild AS phenotypes without hearing loss or ocular abnormalities. Renal biopsies of different family members also revealed the presence of the α3(IV), α4(IV), and α5(IV) chains in the glomerular basement membrane. In our study, we introduced the mutation corresponding to Cys1638Tyr into the α5(IV) chain and characterized the mutant chain. In cells containing the mutant-type α5(IV) chain, heterotrimer formation in the cells and secretion of the α5(IV) chain in the monomeric form from the cells were markedly decreased compared with cells containing the wild-type chain. However, the heterotrimer that was formed from the mutant chain was still able to be secreted from the cells. The residual ability of the mutant chain may have led to the unique phenotypes found in the AS family with the Cys1638Tyr mutation.
References
Tryggvason K, Martin P (2001) Alport syndrome and basement membrane collagen. In: Scriver CR, Beaudet AL, Sly WS, Valle D (eds) The metabolic and molecular bases of inherited disease, vol 4. McGraw-Hill, New York, pp 5453–5466
Thorner PS (2007) Alport syndrome and thin basement membrane nephropathy. Nephron Clin Pract 106:c82–c88
Hudson BG, Tryggvason K, Sundaramoorthy M, Neilson EG (2003) Alport’s syndrome, Goodpasture’s syndrome, and type IV collagen. N Engl J Med 348:2543–2556
Byers PH (2001) Disorders of collagen biosynthesis and structure. In: Scriver CR, Beaudet AL, Sly WS, Valle D (eds) The metabolic and molecular bases of inherited disease, vol 4. McGraw-Hill, New York, pp 5241–5285
Nakanishi K, Yoshikawa N, Iijima K, Kitagawa K, Nakamura H, Ito H, Yoshioka K, Kagawa M, Sado Y (1994) Immunohistochemical study of α1-5 chains of type IV collagen in hereditary nephritis. Kidney Int 46:1413–1421
Jais JP, Knebelmann B, Giatras I, Marchi MD, Rizzoni G, Renieri A, Weber M, Gross O, Netzer KO, Flinter F, Pirson Y, Verellen C, Wieslander J, Persson U, Tryggvason K, Martin P, Hertz JM, Schröder C, Sanak M, Krejcova S, Carvalho MF, Saus J, Antignac C, Smeets H, Gubler MC (2000) X-linked Alport syndrome: natural history in 195 families and genotype-phenotype correlations in males. J Am Soc Nephrol 11:649–657
Kobayashi T, Uchiyama M (2003) Characterization of assembly of recombinant type IV collagen α3, α4, and α5 chains in transfected cell strains. Kidney Int 64:1986–1996
Kobayashi T, Kakihara T, Uchiyama M (2008) Mutational analysis of type IV collagen α5 chain, with respect to heterotrimer formation. Biochem Biophys Res Commun 366:60–65
Wilson JC, Yoon HS, Walker RJ, Eccles MR (2007) A novel Cys1638Tyr NC1 domain substitution in α5(IV) collagen causes Alport syndrome with late onset renal failure without hearing loss or eye abnormalities. Nephrol Dial Transplant 22:1338–1446
Niwa H, Yamamura KI, Miyazaki JI (1991) Efficient selection for high-expression transfectants with a novel eukaryotic vector. Gene 108:193–200
Khoshnoodi J, Cartailler JP, Alvares K, Veis A, Hudson BG (2006) Molecular recognition in the assembly of collagens: terminal noncollagenous domains are key recognition modules in the formation of triple helical protomers. J Biol Chem 281:38117–38121
Hudson BG (2004) The molecular basis of Goodpasture and Alport syndromes: beacons for the discovery of the collagen IV family. J Am Soc Nephrol 15:2514–2527
Miner JH, Sanes JR (1994) Collagen IV α3, α4, and α5 chains in rodent basal laminae: sequence, distribution, association with laminins, and developmental switches. J Cell Biol 127:879–891
Acknowledgments
We wish to thank Dr. Jun-ichi Miyazaki for kindly providing the pCAGGS expression vector. This work was supported by a Grant-in-Aid for Scientific Research (©) (No.20591273) from the Japan Society for the Promotion of Science.
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Kobayashi, T., Uchiyama, M. Mutant-type α5(IV) collagen in a mild form of Alport syndrome has residual ability to form a heterotrimer. Pediatr Nephrol 25, 1169–1172 (2010). https://doi.org/10.1007/s00467-009-1433-1
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DOI: https://doi.org/10.1007/s00467-009-1433-1