Immunoglobulin-like and fibronectin type III domain-containing protein 1 (IGFN1)

Immunoglobulin-like and fibronectin type III domain-containing protein 1 (IGFN1) is a structural protein predominantly expressed in skeletal muscle, encoded by the Igfn1 gene[1][2]. IGFN1 contains multiple immunoglobulin-like and fibronectin type III domains and localizes to the Z-disc of the sarcomere, where it acts largely as a scaffold for other structural and cytoskeletal proteins[1][2]. It does not have enzymatic activity but facilitates structural integrity and cytoskeletal remodeling, particularly influencing actin polymerization and myoblast fusion[1][2]. Disruption of IGFN1 leads to defects in muscle cell fusion and differentiation, and increased globular:filamentous actin ratios, indicating reduced actin polymerization[1][2]. IGFN1 interacts with several sarcomeric proteins (such as filamin C, titin, α-actinin) and with the actin-nucleating protein COBL, modulating its activity and localization[1]. Although IGFN1 is associated with muscle disease phenotypes in animal models, it is not currently considered a classical therapeutic target, receptor, enzyme, or transporter[1][2]. It lacks an enzymatic domain and is not targeted by approved drugs or used as a biomarker in clinical practice[1][2].

Other names

EEF1A2-binding protein 1KY-interacting protein 1IGFN1EEF1A2BP1DKFZp434B1231