The lymphocyte function-associated antigen-1 receptor costimulates plasma membrane Ras via phospholipase D2

Authors:
Mor A, Campi G, Du G, Zheng Y, Foster DA, Dustin ML, Philips MR
In:
Source: Nat Cell Biol
Publication Date: (2007)
Issue: 9(6): 713-9
Research Area:
Immunotherapy / Hematology
Cells used in publication:
Jurkat
Species: human
Tissue Origin: blood
T cell, mouse - BALB/c
Species: mouse
Tissue Origin: blood
T cell, mouse, stim
Species: mouse
Tissue Origin: blood
Jurkat-modified
Species: human
Tissue Origin:
Platform:
Nucleofectorâ„¢ I/II/2b
Abstract
Ras activation as a consequence of antigen receptor (T-cell receptor; TCR) engagement on T lymphocytes is required for T-cell development, selection and function. Lymphocyte function-associated antigen-1 (LFA-1) mediates lymphocyte adhesion, stabilization of the immune synapse and bidirectional signalling. Using a fluorescent biosensor we found that TCR activation with or without costimulation of CD28 led to activation of Ras only on the Golgi apparatus, whereas costimulation with LFA-1 induced Ras activation on both the Golgi and the plasma membrane. Ras activation on both compartments required RasGRP1, an exchange factor regulated by calcium and diacylglycerol (DAG), but phospholipase C (PLC) activity was required only for activation on the Golgi. Engagement of LFA-1 increased DAG levels at the plasma membrane by stimulating phospholipase D (PLD). PLD2 and phosphatidic acid phosphatase (PAP) were required for Ras activation on the plasma membrane. Thus, LFA-1 acts through PLD2 to reshape the pattern of Ras activation downstream of the TCR.