Department of Orthopaedic Surgery, Washington University, St Louis, United States; Shriners Hospitals for Children, St. Louis, United States; Department of Cell Biology, Duke University, Durham, United States; Center of Regenerative Medicine, Washington University, St Louis, United States
Catherine C Gloss
Department of Orthopaedic Surgery, Washington University, St Louis, United States; Shriners Hospitals for Children, St. Louis, United States; Center of Regenerative Medicine, Washington University, St Louis, United States
Jeremiah Lorentz
Department of Orthopaedic Surgery, Washington University, St Louis, United States; Shriners Hospitals for Children, St. Louis, United States; Center of Regenerative Medicine, Washington University, St Louis, United States
Ruhang Tang
Department of Orthopaedic Surgery, Washington University, St Louis, United States; Shriners Hospitals for Children, St. Louis, United States; Center of Regenerative Medicine, Washington University, St Louis, United States
Jonathan M Brunger
Department of Biomedical Engineering, Vanderbilt University, Nashville, United States
Audrey McAlinden
Department of Orthopaedic Surgery, Washington University, St Louis, United States; Shriners Hospitals for Children, St. Louis, United States; Center of Regenerative Medicine, Washington University, St Louis, United States
Bo Zhang
Center of Regenerative Medicine, Washington University, St Louis, United States
Department of Orthopaedic Surgery, Washington University, St Louis, United States; Shriners Hospitals for Children, St. Louis, United States; Center of Regenerative Medicine, Washington University, St Louis, United States
The roles of long noncoding RNAs (lncRNAs) in musculoskeletal development, disease, and regeneration remain poorly understood. Here, we identified the novel lncRNA GRASLND (originally named RNF144A-AS1) as a regulator of mesenchymal stem cell (MSC) chondrogenesis. GRASLND, a primate-specific lncRNA, is upregulated during MSC chondrogenesis and appears to act directly downstream of SOX9, but not TGF-β3. We showed that the silencing of GRASLND resulted in lower accumulation of cartilage-like extracellular matrix in a pellet assay, while GRASLND overexpression – either via transgene ectopic expression or by endogenous activation via CRISPR-dCas9-VP64 – significantly enhanced cartilage matrix production. GRASLND acts to inhibit IFN-γ by binding to EIF2AK2, and we further demonstrated that GRASLND exhibits a protective effect in engineered cartilage against interferon type II. Our results indicate an important role of GRASLND in regulating stem cell chondrogenesis, as well as its therapeutic potential in the treatment of cartilage-related diseases, such as osteoarthritis.