H19 activates Wnt signaling and promotes osteoblast differentiation by functioning as a competing endogenous RNA

Sci Rep. 2016 Feb 8;6:20121. doi: 10.1038/srep20121.

Abstract

Bone homeostasis is tightly orchestrated and maintained by the balance between osteoblasts and osteoclasts. Recent studies have greatly expanded our understanding of the molecular mechanisms of cellular differentiation. However, the functional roles of non-coding RNAs particularly lncRNAs in remodeling bone architecture remain elusive. In our study, lncRNA H19 was found to be upregulated during osteogenesis in hMSCs. Stable expression of H19 significantly accelerated in vivo and in vitro osteoblast differentiation. Meanwhile, by using bioinformatic investigations and RIP assays combined with luciferase reporter assays, we demonstrated that H19 functioned as an miRNA sponge for miR-141 and miR-22, both of which were negative regulators of osteogenesis and Wnt/β-catenin pathway. Further investigations revealed that H19 antagonized the functions of these two miRNAs and led to de-repression of their shared target gene β-catenin, which eventually activated Wnt/β-catenin pathway and hence potentiated osteogenesis. In addition, we also identified a novel regulatory feedback loop between H19 and its encoded miR-675-5p. And miR-675-5p was found to directly target H19 and counteracted osteoblast differentiation. To sum up, these observations indicate that the lncRNA H19 modulates Wnt/β-catenin pathway by acting as a competing endogenous RNA, which may shed light on the functional role of lncRNAs in coordinating osteogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Alkaline Phosphatase / genetics
  • Alkaline Phosphatase / metabolism
  • Animals
  • Base Sequence
  • Blotting, Western
  • Cell Differentiation
  • Cell Line
  • Core Binding Factor Alpha 1 Subunit / genetics
  • Core Binding Factor Alpha 1 Subunit / metabolism
  • Genes, Reporter
  • Humans
  • Immunoprecipitation
  • MicroRNAs / antagonists & inhibitors
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Osteoblasts / cytology
  • Osteoblasts / metabolism
  • Osteogenesis
  • RNA, Long Noncoding / genetics
  • RNA, Long Noncoding / metabolism*
  • Real-Time Polymerase Chain Reaction
  • Sequence Alignment
  • Wnt Proteins / antagonists & inhibitors
  • Wnt Proteins / genetics
  • Wnt Proteins / metabolism*
  • Wnt Signaling Pathway*
  • beta Catenin / antagonists & inhibitors
  • beta Catenin / genetics
  • beta Catenin / metabolism

Substances

  • 3' Untranslated Regions
  • Core Binding Factor Alpha 1 Subunit
  • H19 long non-coding RNA
  • MicroRNAs
  • RNA, Long Noncoding
  • Wnt Proteins
  • beta Catenin
  • Alkaline Phosphatase