{
  "abstract": "Collagen I provides mechanical stability to organs and plays a critical role in several physiological processes such as wound healing and bone remodeling. Its ability to form fibrils depends on the proteolytic conversion of soluble procollagen I into mature protomers. However, the mechanistic aspects of this critical step have been difficult to analyze due to the lack of recombinant procollagen I suitable for structural and biochemical analyses. Here, we describe the successful production and purification of a heterotrimeric mini-procollagen I [α1(I) 2 α2(I)] together with its homotrimeric counterpart [α1(I) 3 ] in HEK293-F cells. These tools were used to probe the specific role of the α2(I) chain both in procollagen I assembly and proteolytic maturation. While the presence of α2(I) in the heterotrimer does not strengthen trimer interfaces on its own, as revealed by cryo-electron microscopy, it provides a clear functional advantage to the procollagen substrate that is cleaved more efficiently by bone morphogenetic protein 1 (BMP-1) than the homotrimer. Furthermore, we demonstrate that the first cleavage event in the heterotrimer is at the level of the α2(I) chain, through a mechanism involving its C-telopeptide and a specific PRS motif close to the cleavage site. The preferential cleavage of α2(I) by BMP-1 can be partially corrected in the presence of PCPE-1 (procollagen C-proteinase enhancer 1) but the efficacy of the correction depends on its position on the procollagen trimer. Finally, we solved the high-resolution structure of the complex between the heterotrimer and PCPE-1 and proposed a new mechanism to explain the enhancing activity of PCPE-1.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "Oskar Lipiński"
    },
    {
      "name": "Cindy Dieryckx"
    },
    {
      "name": "Natacha Mariano"
    },
    {
      "name": "Priscillia Lagoutte"
    },
    {
      "name": "Hok Sau Kwong"
    },
    {
      "name": "Sandrine Vadon-Le Goff"
    },
    {
      "name": "Loïc Carrique"
    },
    {
      "name": "Catherine Moali"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/esq039g2kzm4e.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.10.03.756409",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.10.03.756409v1.full",
  "id": "esq039g2kzm4e",
  "issns": [],
  "landing_url": "https://hal.science/hal-05782088v1",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "biochemistry"
    ],
    [
      "hal",
      "0.sdv"
    ],
    [
      "openalex",
      "2502|Collagen: Extraction and Characterization"
    ]
  ],
  "openalex": "W7220718900",
  "pdf_url": "https://hal.science/hal-05782088/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-03",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/esq039g2kzm4e.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:00Z",
      "native_id": "hal-05782088",
      "source": "hal",
      "url": "https://hal.science/hal-05782088v1"
    },
    {
      "first_seen": "2026-10-30T12:26:14Z",
      "native_id": "10.64898/2026.10.03.756409",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.10.03.756409v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:2502|Collagen: Extraction and Characterization",
      "subfield": "materials-polymers"
    }
  ],
  "title": "A recombinant heterotrimeric mini-procollagen I reveals new functional and structural roles for the α2(I) chain",
  "title_text": "A recombinant heterotrimeric mini-procollagen I reveals new functional and structural roles for the α2(I) chain",
  "type": "preprint",
  "updated_at": "2026-10-30T12:26:14Z",
  "url": "https://research.draconitic.com/paper/esq039g2kzm4e",
  "venue": "HAL",
  "versions": []
}