The COL5A1 gene encodes for the α1 chain of type V collagen, a minor fibrillar collagen that is an important regulator of collagen fibrillogenesis. Several polymorphisms, including rs12722 (C/T), within the 3′-UTR of COL5A1 are associated with chronic Achilles tendinopathy and other musculoskeletal soft tissue injuries as well as exercise-related phenotypes. It is hypothesised that polymorphisms within the 3′-UTR regulate the amount of the α1(V) chain synthesised and type V collagen production. This in turn influencing the mechanical properties of tendons and other musculoskeletal soft tissues. In our laboratories, two major functional forms, namely the T- and C-allelic forms of the COL5A1 3′-UTR, were identified and associated predominately with severe chronic Achilles tendinopathy and healthy asymptomatic control individuals, respectively. To further investigate the functional differences between the two major 3′-UTR functional forms as well as to start mapping the regions which are responsible for the tendinopathic phenotype, skin biopsies from donors having a known genotype at rs12722 and primary fibroblast cell lines were established in order to quantify COL5A1 and COL1A1 expression levels in a pilot study. Lastly, in preliminary RNA EMSAs, biotinylated C- and T-allelic RNA probes for a specific 57bp functional region within the 3′-UTR were incubated with either fibroblast nuclear or cytoplasmic protein extracts to investigate putative distinguishing RNA:RBP complex formation.Introduction
Materials and Methods
