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The N-terminal N5 subdomain of the alpha 3(VI) chain is important for collagen VI microfibril formation

Fitzgerald, Jamie; Mörgelin, Matthias LU ; Selan, Carly; Wiberg, Charlotte; Keene, Douglas R.; Lamande, Shireen R. and Bateman, John F. (2001) In Journal of Biological Chemistry 276(1). p.187-193
Abstract
Collagen VI assembly is unique within the collagen superfamily in that the alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains associate intracellularly to form triple helical monomers, and then dimers and tetramers, which are secreted from the cell. Secreted tetramers associate end-to-end to form the distinctive extracellular microfibrils that are found in virtually all connective tissues. Although the precise protein interactions involved in this process are unknown, the N-terminal globular regions, which are composed of multiple copies of von Willebrand factor type A-like domains, are likely to play a critical role in microfibril formation, because they are exposed at both ends of the tetramers. To explore the role of these subdomains in... (More)
Collagen VI assembly is unique within the collagen superfamily in that the alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains associate intracellularly to form triple helical monomers, and then dimers and tetramers, which are secreted from the cell. Secreted tetramers associate end-to-end to form the distinctive extracellular microfibrils that are found in virtually all connective tissues. Although the precise protein interactions involved in this process are unknown, the N-terminal globular regions, which are composed of multiple copies of von Willebrand factor type A-like domains, are likely to play a critical role in microfibril formation, because they are exposed at both ends of the tetramers. To explore the role of these subdomains in collagen VI intracellular and extracellular assembly, alpha 3(VI) cDNA expression constructs with sequential N-terminal deletions were stably transfected into SaOS-2 cells, producing cell lines that express alpha 3(VI) chains with N-terminal globular domains containing modules N9-N1, N6-N1, N5-N1, N4-N1, N3-N1, or N1, as well as the complete triple helix and C-terminal globular domain (C1-C5). All of these transfected alpha 3(VI) chains were able to associate with endogenous alpha 1(VI) and alpha 2(VI) to form collagen VI monomers, dimers, and tetramers, which were secreted. Importantly, cells that expressed alpha 3(VI) chains containing the N5 subdomain, alpha 3(VI) N9-C5, N6-C5, and N5-C5, formed microfibrils and deposited a collagen VI matrix. In contrast, cells that expressed the shorter alpha 3(VI) chains, N4-C5, N3-C5, and N1-C5, were severely compromised in their ability to form end-to-end tetramer assemblies and failed to deposit a collagen VI matrix. These data demonstrate that the alpha 3(VI) N5 module is critical for microfibril formation, thus identifying a functional role for a specific type A subdomain in collagen VI assembly. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Biological Chemistry
volume
276
issue
1
pages
187 - 193
publisher
ASBMB
external identifiers
  • pmid:11027693
  • scopus:0035808443
ISSN
1083-351X
DOI
10.1074/jbc.M008173200
language
English
LU publication?
yes
id
d1eca5e8-2bfc-4673-96f7-7c887b5c7194 (old id 1120841)
date added to LUP
2008-06-27 11:12:46
date last changed
2018-05-29 12:25:53
@article{d1eca5e8-2bfc-4673-96f7-7c887b5c7194,
  abstract     = {Collagen VI assembly is unique within the collagen superfamily in that the alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains associate intracellularly to form triple helical monomers, and then dimers and tetramers, which are secreted from the cell. Secreted tetramers associate end-to-end to form the distinctive extracellular microfibrils that are found in virtually all connective tissues. Although the precise protein interactions involved in this process are unknown, the N-terminal globular regions, which are composed of multiple copies of von Willebrand factor type A-like domains, are likely to play a critical role in microfibril formation, because they are exposed at both ends of the tetramers. To explore the role of these subdomains in collagen VI intracellular and extracellular assembly, alpha 3(VI) cDNA expression constructs with sequential N-terminal deletions were stably transfected into SaOS-2 cells, producing cell lines that express alpha 3(VI) chains with N-terminal globular domains containing modules N9-N1, N6-N1, N5-N1, N4-N1, N3-N1, or N1, as well as the complete triple helix and C-terminal globular domain (C1-C5). All of these transfected alpha 3(VI) chains were able to associate with endogenous alpha 1(VI) and alpha 2(VI) to form collagen VI monomers, dimers, and tetramers, which were secreted. Importantly, cells that expressed alpha 3(VI) chains containing the N5 subdomain, alpha 3(VI) N9-C5, N6-C5, and N5-C5, formed microfibrils and deposited a collagen VI matrix. In contrast, cells that expressed the shorter alpha 3(VI) chains, N4-C5, N3-C5, and N1-C5, were severely compromised in their ability to form end-to-end tetramer assemblies and failed to deposit a collagen VI matrix. These data demonstrate that the alpha 3(VI) N5 module is critical for microfibril formation, thus identifying a functional role for a specific type A subdomain in collagen VI assembly.},
  author       = {Fitzgerald, Jamie and Mörgelin, Matthias and Selan, Carly and Wiberg, Charlotte and Keene, Douglas R. and Lamande, Shireen R. and Bateman, John F.},
  issn         = {1083-351X},
  language     = {eng},
  number       = {1},
  pages        = {187--193},
  publisher    = {ASBMB},
  series       = {Journal of Biological Chemistry},
  title        = {The N-terminal N5 subdomain of the alpha 3(VI) chain is important for collagen VI microfibril formation},
  url          = {http://dx.doi.org/10.1074/jbc.M008173200},
  volume       = {276},
  year         = {2001},
}