Collagen type I (COL1) (COL1)

Collagen type I is the most abundant structural protein in the human body, serving as the primary component of the extracellular matrix (ECM) in skin, bone, tendons, and ligaments (PMID: 28213350). It is a fibrillar collagen typically composed of two alpha-1 chains and one alpha-2 chain that assemble into a triple-helical tropocollagen molecule, which further organizes into high-tensile-strength fibrils (UniProt: P02452). Biologically, these fibrils provide mechanical support, regulate cell adhesion through integrin and discoidin domain receptor (DDR) binding, and play a critical role in tissue development and repair (PMID: 30635914). In pathology, excessive deposition and cross-linking of collagen type I fibrils are hallmarks of fibrotic diseases such as pulmonary fibrosis, liver cirrhosis, and systemic sclerosis (PMID: 24732768). Conversely, genetic mutations in the COL1A1 or COL1A2 genes lead to structural deficiencies seen in Osteogenesis imperfecta and Ehlers-Danlos syndrome (PMID: 28213350). Therapeutic strategies targeting these fibrils include the use of collagenase enzymes to enzymatically degrade pathological collagen plaques in conditions like Dupuytren's contracture and Peyronie's disease (FDA: Xiaflex). Additionally, research focuses on small molecules and monoclonal antibodies that inhibit the synthesis, secretion, or cross-linking of collagen to treat chronic fibrotic disorders (PMID: 30635914).

Other names

Type I collagenCollagen alpha-1(I) chainCollagen alpha-2(I) chainCollagen type I fibrilsFibrillar collagen type I

Direct enzymatic cleavage of the triple-helical collagen fibrils into smaller peptides, or indirect suppression of fibril assembly by inhibiting pro-fibrotic signaling pathways and collagen gene expression.