Identification of T-cadherin as a novel target of DNA methyltransferase 3B and its role in the suppression of nerve growth factor-mediated neurite outgrowth in PC12 cells

J Biol Chem. 2006 May 12;281(19):13604-13611. doi: 10.1074/jbc.M513278200. Epub 2006 Mar 14.

Abstract

Previously we showed that DNA methyltransferase 3b (Dnmt3b) is required for nerve growth factor (NGF)-induced differentiation of PC12 cells to neuronal phenotype. The present study identified T-cadherin (T-Cad) as one of the targets of Dnmt3b by chromatin immunoprecipitation (ChIP) assay. Combined bisulfite restriction analysis and bisulfite sequencing showed that T-Cad promoter was sparsely methylated in PC12 cells. ChIP-CHOP analysis demonstrated that Dnmt3b is associated with T-Cad promoter irrespective of its methylation status. The mRNA and protein levels of T-Cad were markedly elevated in cells depleted of Dnmt3b by antisense or small interfering RNA. Suppression of T-Cad promoter activity by Dnmt3b was independent of its catalytic activity, which was consistent with the insignificant change in T-Cad promoter methylation status in Dnmt3b-depleted cells. In contrast, deletion of its N-terminal ATRX and PWWP domain abolished its repressor function. Association of histone deacetylase 2 (Hdac2) with T-Cad promoter and restoration of the promoter activity from Dnmt3b-mediated suppression upon treatment with Hdac inhibitor indicated involvement of histone deacetylation in this process. NGF-induced neurite outgrowth was inhibited in a dose dependent manner upon ectopic expression of T-Cad in PC12 cells. Immunofluorescence studies showed that T-Cad was redistributed upon NGF treatment, as evident from its concentration in axon growth cones as opposed to its localization at cell-cell contact region in undifferentiated cells. These results demonstrate a novel role of T-Cad in the NGF-mediated differentiation of PC12 cells to neuronal phenotype.

Publication types

  • Research Support, N.I.H., Extramural
  • Retracted Publication

MeSH terms

  • Animals
  • Cadherins / metabolism*
  • Cell Differentiation
  • DNA (Cytosine-5-)-Methyltransferases / metabolism*
  • DNA Methyltransferase 3B
  • Down-Regulation
  • Gene Expression Regulation, Enzymologic
  • Nerve Growth Factor / pharmacology*
  • Neurites / drug effects*
  • Neurites / enzymology
  • Neurites / metabolism*
  • PC12 Cells
  • Rats
  • Substrate Specificity

Substances

  • Cadherins
  • H-cadherin
  • Nerve Growth Factor
  • DNA (Cytosine-5-)-Methyltransferases