Collagen IV diseases: A focus on the glomerular basement membrane in Alport syndrome

D Cosgrove, S Liu - Matrix Biology, 2017 - Elsevier
D Cosgrove, S Liu
Matrix Biology, 2017Elsevier
Alport syndrome is the result of mutations in any of three type IV collagen genes, COL4A3,
COL4A4, or COL4A5. Because the three collagen chains form heterotrimers, there is an
absence of all three proteins in the basement membranes where they are expressed. In the
glomerulus, the mature glomerular basement membrane type IV collagen network, normally
comprised of two separate networks, α3 (IV)/α4 (IV)/α5 (IV) and α1 (IV)/α2 (IV), is comprised
entirely of collagen α1 (IV)/α2. This review addresses the current state of our knowledge …
Abstract
Alport syndrome is the result of mutations in any of three type IV collagen genes, COL4A3, COL4A4, or COL4A5. Because the three collagen chains form heterotrimers, there is an absence of all three proteins in the basement membranes where they are expressed. In the glomerulus, the mature glomerular basement membrane type IV collagen network, normally comprised of two separate networks, α3(IV)/α4(IV)/α5(IV) and α1(IV)/α2(IV), is comprised entirely of collagen α1(IV)/α2. This review addresses the current state of our knowledge regarding the consequence of this change in basement membrane composition, including both the direct, via collagen receptor binding, and indirect, regarding influences on glomerular biomechanics. The state of our current understanding regarding mechanisms of glomerular disease initiation and progression will be examined, as will the current state of the art regarding emergent therapeutic approaches to slow or arrest glomerular disease in Alport patients.
Elsevier