Cav3.2 T-type calcium channel is required for the NFAT-dependent Sox9 expression in tracheal cartilage

Proc Natl Acad Sci U S A. 2014 May 13;111(19):E1990-8. doi: 10.1073/pnas.1323112111. Epub 2014 Apr 28.

Abstract

Intracellular Ca(2+) transient is crucial in initiating the differentiation of mesenchymal cells into chondrocytes, but whether voltage-gated Ca(2+) channels are involved remains uncertain. Here, we show that the T-type voltage-gated Ca(2+) channel Cav3.2 is essential for tracheal chondrogenesis. Mice lacking this channel (Cav3.2(-/-)) show congenital tracheal stenosis because of incomplete formation of cartilaginous tracheal support. Conversely, Cav3.2 overexpression in ATDC5 cells enhances chondrogenesis, which could be blunted by both blocking T-type Ca(2+) channels and inhibiting calcineurin and suggests that Cav3.2 is responsible for Ca(2+) influx during chondrogenesis. Finally, the expression of sex determination region of Y chromosome (SRY)-related high-mobility group-Box gene 9 (Sox9), one of the earliest markers of committed chondrogenic cells, is reduced in Cav3.2(-/-) tracheas. Mechanistically, Ca(2+) influx via Cav3.2 activates the calcineurin/nuclear factor of the activated T-cell (NFAT) signaling pathway, and a previously unidentified NFAT binding site is identified within the mouse Sox9 promoter using a luciferase reporter assay and gel shift and ChIP studies. Our findings define a previously unidentified mechanism that Ca(2+) influx via the Cav3.2 T-type Ca(2+) channel regulates Sox9 expression through the calcineurin/NFAT signaling pathway during tracheal chondrogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcineurin / metabolism
  • Calcium Channels, T-Type / genetics
  • Calcium Channels, T-Type / physiology*
  • Cartilage / cytology
  • Cartilage / embryology*
  • Cartilage / physiology
  • Cells, Cultured
  • Chondrocytes / cytology
  • Chondrocytes / physiology*
  • Chondrogenesis / genetics*
  • Chondrogenesis / physiology
  • Female
  • Gene Expression Regulation, Developmental
  • Male
  • Mice
  • Mice, 129 Strain
  • Mice, Inbred ICR
  • Mice, Knockout
  • NFATC Transcription Factors / metabolism
  • Promoter Regions, Genetic / physiology
  • SOX9 Transcription Factor / genetics*
  • SOX9 Transcription Factor / metabolism
  • Trachea / cytology
  • Trachea / embryology*
  • Trachea / physiology

Substances

  • Cacna1h protein, mouse
  • Calcium Channels, T-Type
  • NFATC Transcription Factors
  • SOX9 Transcription Factor
  • Sox9 protein, mouse
  • Calcineurin