This family of proteins is found in eukaryotes and include SNORC, a cartilage specific small membrane proteoglycan that plays a role in the regulation of chondrocyte maturation and postnatal endochondral ossification [1,2]. There are two conserved sequence motifs: LGPGAI and LRKF.

1: Snorc is a novel cartilage specific small membrane proteoglycan expressed in differentiating and articular chondrocytes. Heinonen J, Taipaleenmaki H, Roering P, Takatalo M, Harkness L, Sandholm J, Uusitalo-Jarvinen H, Kassem M, Kiviranta I, Laitala-Leinonen T, Saamanen AM; Osteoarthritis Cartilage. 2011;19:1026-1035. PMID:21624478

2: Defects in chondrocyte maturation and secondary ossification in mouse knee joint epiphyses due to Snorc deficiency. Heinonen J, Zhang FP, Surmann-Schmitt C, Honkala S, Stock M, Poutanen M, Saamanen AM; Osteoarthritis Cartilage. 2017;25:1132-1142. PMID:28323137