(A) Exposing mesenchymal stem cells (MSCs) to the growth factor TGFβ3 activates the expression of the Sox9 gene, which triggers the production of a long non-coding RNA called GRASLND. (B) GRASLND binds to the kinase EIF2AK2 (blue), which blocks the inhibitory phosphorylation of the protein EIF2A (green). This, in turn, promotes the expression of 'prochondrogenic factors' that encourage the production of molecules, such as proteoglycans, which form cartilage; the cell is said to have a 'chondrogenic' phenotype. (C) When GRASLND is depleted from mesenchymal stem cells, the kinase EIF2AK2 probably phosphorylates EIF2A (represented here by the ‘-P*’). This activates the Type II IFN-γ response, which ultimately leads to a reduction in proteoglycan expression and a loss of the chondrogenic phenotype. GRASLND: glycosaminoglycan regulatory associated long non-coding RNA; EIF2A: eukaryotic translation initiation factor two alpha; EIF2AK2: EIF2A kinase; TGFβ3: transforming growth factor beta 3. Figure created using BioRender (BioRender.com).