Long non-coding RNA GAS5 inhibits osteogenic differentiation through miR-382-3p/ TAF1 signaling

Abstract

Background: Long non-coding RNAs (lncRNAs) have been confirmed as important regulators during osteogenic differentiation. Previous researches have disclosed that growth arrest-specific transcript 5 ( GAS5 ) can promote the osteogenic differentiation of human bone marrow mesenchyml stem cells (hBMSCs), but the underlying regulatory mechanism of GAS5 during the osteogenic differentiation of hBMSCs is unclear. Methods: Osteogenic differentiation was induced in hBMSCs by using osteogenic medium (OM). Gene expression was assessed by RT-qPCR or western blot assays as needed. ALP activity, ALP staining and ARS staining assays were performed to evaluate the impact of GAS5 , microRNA-382-3p (miR-382-3p) and TATA-box binding protein associated factor 1 ( TAF1 ) on osteogenic differentiation in vitro . The interaction among GAS5 , miR-382-3p and TAF1 was determined by RIP, ChIP and luciferase reporter assays. Results: Expression of GAS5 (transcript variant 2) was down-regulated during the osteogenic differentiation of hBMSCs and its overexpression retarded the osteogenic differentiation of hBMSCs. GAS5 inhibited miR-382-3p through targeting RNA-directed microRNA degradation (TDMD). MiR-382-3p down-regulation partially offset the promoted osteogenic differentiation of hBMSCs upon GAS5 silencing. TAF1 negatively modulated osteogenic differentiation and it activated GAS5 transcription so as to form a positive GAS5 /miR-382-3p/ TAF1 feedback loop in hBMSCs. Conclusion: This research was the first to reveal that the GAS5 /miR-382-3p/ TAF1 feedback loop inhibited the osteogenic differentiation of hBMSCs, which provided new clues for exploring the mechanism of osteogenic differentiation and disclosed the potential of GAS5 as a promising target during osteogenic differentiation.