First Author | Leduc I | Year | 2000 |
Journal | Int Immunol | Volume | 12 |
Issue | 10 | Pages | 1389-96 |
PubMed ID | 11007756 | Mgi Jnum | J:110498 |
Mgi Id | MGI:3640420 | Doi | 10.1093/intimm/12.10.1389 |
Citation | Leduc I, et al. (2000) The Pim-1 kinase stimulates maturation of TCRbeta-deficient T cell progenitors: implications for the mechanism of Pim-1 action. Int Immunol 12(10):1389-96 |
abstractText | We demonstrate that overexpression of Pim-1, a cytoplasmic serine/threonine kinase of poorly defined function, results in the development of substantial numbers of CD4(+)CD8(+) double-positive thymocytes in two independent knock-out mouse models (i.e. the RAG-1-deficient and TCRbeta gene enhancer-deleted mice) in which production of a functionally rearranged TCRbeta gene (hence the pre-TCR) is impaired. This activity of Pim-1, however, does not affect signaling through the Ras/Raf/MAP kinase cascade nor signaling which mediates suppression of TCRbeta gene recombination (i.e. allelic exclusion). While overexpression of Pim-1 positively affects cell cycle progression in selected CD4(-)CD8(-) double-negative precursors, it did not affect expression of components of the cell cycle machinery, with the exception of the G(1)-specific phosphatase Cdc25A upon antigen receptor stimulation. We propose that Pim-1 acts downstream, or in parallel, to pre-TCR-mediated selection as one factor involved in the proliferative expansion of beta-selected pre-T cells. |