5K31

Crystal structure of Human fibrillar procollagen type I C-propeptide Homo-trimer

Summary for 5K31

• Entry DOI: 10.2210/pdb5k31/pdb
• Descriptor: Collagen alpha-1(I) chain, CALCIUM ION, GLYCEROL, ... (5 entities in total)
• Functional Keywords: fibrillar collagen, extracellular matrix, fibrosis, structural protein
• Biological source: Homo sapiens (Human)
• Cellular location: Secreted, extracellular space, extracellular matrix : P02452
• Total number of polymer chains: 6
• Total formula weight: 172934.98

Authors

Sharma, U.,Hulmes, D.J.S.,Aghajari, N. (deposition date: 2016-05-19, release date: 2017-03-22, Last modification date: 2024-01-10)

Primary citation

Sharma, U.,Carrique, L.,Vadon-Le Goff, S.,Mariano, N.,Georges, R.N.,Delolme, F.,Koivunen, P.,Myllyharju, J.,Moali, C.,Aghajari, N.,Hulmes, D.J.
Structural basis of homo- and heterotrimerization of collagen I.
Nat Commun, 8:14671-14671, 2017

PubMed Abstract: Fibrillar collagen molecules are synthesized as precursors, procollagens, with large propeptide extensions. While a homotrimeric form (three α1 chains) has been reported in embryonic tissues as well as in diseases (cancer, fibrosis, genetic disorders), collagen type I usually occurs as a heterotrimer (two α1 chains and one α2 chain). Inside the cell, the role of the C-terminal propeptides is to gather together the correct combination of three α chains during molecular assembly, but how this occurs for different forms of the same collagen type is so far unknown. Here, by structural and mutagenic analysis, we identify key amino acid residues in the α1 and α2 C-propeptides that determine homo- and heterotrimerization. A naturally occurring mutation in one of these alters the homo/heterotrimer balance. These results show how the C-propeptide of the α2 chain has specifically evolved to permit the appearance of heterotrimeric collagen I, the major extracellular building block among the metazoa.

PubMed: 28281531
DOI: 10.1038/ncomms14671

Experimental method

X-RAY DIFFRACTION (2.2 Å)