Rasal3-mediated T Cell Survival Is Essential for Inflammatory Responses

Biochem Biophys Res Commun. 2018 Jan 29;496(1):25-30. doi: 10.1016/j.bbrc.2017.12.159. Epub 2017 Dec 29.

Abstract

Fine regulation of the Ras/mitogen-activating protein kinase (MAPK) pathway is crucial in controlling the survival, proliferation, and development of various types of cells. Ras-activating protein-like 3 (Rasal3) is a T cell-specific Ras GTPase-activating protein that negatively regulates T cell receptor (TCR)-induced activation of Ras/MAPK pathway. Rasal3-deficient mice showed a decreased number of naive T cells because Rasal3 is required for the survival of naive T cells. In the current study, we observed ameliorated Type1 T helper (Th1) cell- and Type2 T helper (Th2) cell-dependent contact hypersensitivity reactions in Rasal3-deficient mice, along with a marked shortage of T cells at regional lymph node. Activated Rasal3-deficient T cells showed an increased cell death with reduced Bcl2 expression, suggesting that Rasal3 is required for the survival of not only naïve T cells but also activated T cells. Collectively, Rasal3 controls the magnitude of inflammatory responses through the survival of both naive T cells and activated T cells in vivo.

Keywords: Apoptosis; Contact hypersensitivity (CHS); Rasal3.

MeSH terms

  • Animals
  • Cell Survival / immunology*
  • Dermatitis, Contact / immunology*
  • Dermatitis, Contact / pathology*
  • Lymphocyte Activation / immunology*
  • Mice
  • Mice, Inbred C57BL
  • T-Lymphocytes / immunology*
  • ras GTPase-Activating Proteins / immunology*

Substances

  • RASAL3 protein, mouse
  • ras GTPase-Activating Proteins