CKIP-1 suppresses odontoblastic differentiation of dental pulp stem cells via BMP2 pathway and can interact with NRP1

Connect Tissue Res. 2019 Mar;60(2):155-164. doi: 10.1080/03008207.2018.1483355. Epub 2018 Aug 14.

Abstract

Aim: Casein kinase 2 interacting protein-1 (CKIP-1) is a recently discovered intracellular regulator of bone formation, muscle cell differentiation, and tumor cell proliferation. Our study aims to identify the inhibition of BMP2-Smad1/5 signaling by CKIP-1 in odontoblastic differentiation of human dental pulp stem cells (DPSCs).

Materials and methods: DPSCs infected CKIP-1 siRNA or transfected CKIP-1 full-length plasmid were cultured in odontoblastic differentiation medium or added noggin (200 ng/mL) for 21 days. We examined the effects of CKIP-1 on odontoblastic differentiation, mineralized nodules formation, and interaction by western blot, real-time polymerase chain reaction (RT-PCR), alkaline phosphatase (ALP) staining, alizarin red S staining, and immunoprecipitation.

Results: Firstly, we have demonstrated that CKIP-1 expression markedly decreased time-dependently along with cell odontoblastic differentiation. Indeed, the silence of CKIP-1 upregulated odontoblastic differentiation via BMP2-Smad1/5 signaling, while CKIP-1 over-expression had a negative effect on odontoblastic differentiation of DPSCs. Furthermore, CKIP-1 could interact with Neuropilin-1 (NRP1).

Conclusions: This work provides data that advocates a novel perception on odontoblastic differentiation of DPSCs. Therefore, inhibiting the expression of CKIP-1 may be of great significance to the development of dental caries.

Keywords: BMP2-Smad1/5 signaling; Neuropilin-1 (NRP1); casein kinase 2 interacting protein-1 (CKIP-1); dental pulp stem cells (DPSCs); odontoblastic differentiation (OD).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Bone Morphogenetic Protein 2 / metabolism*
  • Carrier Proteins / metabolism
  • Cell Differentiation*
  • Dental Pulp / cytology*
  • Down-Regulation / genetics
  • Humans
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Models, Biological
  • Neuropilin-1 / metabolism*
  • Odontoblasts / cytology*
  • Phenotype
  • Protein Binding
  • Signal Transduction*
  • Smad Proteins / metabolism
  • Stem Cells / cytology*
  • Stem Cells / metabolism
  • Up-Regulation / genetics
  • Young Adult

Substances

  • Bone Morphogenetic Protein 2
  • Carrier Proteins
  • Intracellular Signaling Peptides and Proteins
  • PLEKHO1 protein, human
  • Smad Proteins
  • Neuropilin-1
  • noggin protein