| First Author | Chaffin KE | Year | 1990 |
| Journal | EMBO J | Volume | 9 |
| Issue | 12 | Pages | 3821-9 |
| PubMed ID | 2123451 | Mgi Jnum | J:81268 |
| Mgi Id | MGI:2448670 | Doi | 10.1002/j.1460-2075.1990.tb07600.x |
| Citation | Chaffin KE, et al. (1990) Dissection of thymocyte signaling pathways by in vivo expression of pertussis toxin ADP-ribosyltransferase. EMBO J 9(12):3821-9 |
| abstractText | Stimulation of the T lymphocyte antigen receptor-CD3 complex (TCR-CD3) causes T cell activation by a process associated with increased phosphatidylinositol-specific phospholipase C (PI-PLC) activity. Evidence exists suggesting that GTP-binding (G) proteins, particularly the pertussis toxin (PT)-sensitive Gi proteins, participate in this signal transduction pathway. To clarify the role of Gi proteins in TCR-CD3 signaling, and to investigate other possible functions of Gi molecules in T cells, we expressed the S1 subunit of PT in the thymocytes of transgenic mice using the lymphocyte-specific lck promoter. Transgenic thymocytes contained S1 activity and exhibited profound depletion of Gi protein PT substrates in a manner suggesting their inactivation by S1 in vivo. Nevertheless, treatment of transgenic thymocytes with mitogenic stimuli provoked normal increases in intracellular free Ca2+ concentrations and IL-2 secretion, indicating that Gi proteins are not required for T cell activation. These normal signaling responses notwithstanding, mature thymocytes accumulated in lck-PT mice and did not appear in secondary lymphoid organs or in the circulation. Viewed in the context of the known features of Bordetella pertussis infection, our results suggest that a PT-sensitive signaling process, probably involving Gi proteins, regulates thymocyte emigration. |
