Osteogenesis is a complex biological process which requires the coordination of multiple molecular mechanisms. This research aimed to explore the biological role and underlying regulatory mechanism of circSIPA1L1 during the osteogenic differentiation of stem cells from apical papilla (SCAPs). EdU retention assay, flow cytometry assay, and CCK-8 assay were used to evaluate the proliferation capacity of SCAPs. Western blot assay, alkaline phosphatase (ALP), and alizarin red staining (ARS) were conducted to investigate the biological roles of circSIPA1L1 and miR-204-5p. Fluorescence in situ hybridization was applied for circSIPA1L1 localization. Dual-luciferase reporter assay was performed to prove the interaction of circSIPA1L1 and miR-204-5p. CircSIPA1L1 had no significant effect on the proliferative capacity of SCAPs. CircSIPA1L1 promotes osteogenic differentiation of SCAPs by serving as a miRNA sponge for miR-204-5p. Either knockdown of circSIPA1L1 or overexpression of miR-204-5p significantly suppresses osteogenic differentiation of SCAPs. CircSIPA1L1 upregulates ALPL through targeting miR-204-5p and promotes the osteogenic differentiation of SCAPs.

中文翻译：

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环状RNA SIPA1L1通过miR-204-5p/ALPL通路调控顶端乳头干细胞成骨分化

成骨是一个复杂的生物过程，需要多种分子机制的协调。本研究旨在探讨circSIPA1L1在顶端乳头干细胞（SCAPs）成骨分化过程中的生物学作用和潜在调控机制。EdU保留试验、流式细胞仪试验和CCK-8试验用于评估SCAPs的增殖能力。进行蛋白质印迹分析、碱性磷酸酶 (ALP) 和茜素红染色 (ARS) 以研究 circSIPA1L1 和 miR-204-5p 的生物学作用。荧光原位杂交用于circSIPA1L1定位。进行双荧光素酶报告基因测定以证明 circSIPA1L1 和 miR-204-5p 的相互作用。CircSIPA1L1 对 SCAPs 的增殖能力没有显着影响。CircSIPA1L1 通过充当 miR-204-5p 的 miRNA 海绵促进 SCAP 的成骨分化。circSIPA1L1 的敲低或 miR-204-5p 的过表达都会显着抑制 SCAP 的成骨分化。CircSIPA1L1 通过靶向 miR-204-5p 上调 ALPL 并促进 SCAPs 的成骨分化。