3. Engagement of the TCR causes an early rise in [Ca2+]i
Single-cell response (FACS)
Tsien et al, 1982
Population response

4. Single-cell responses (imaging)
Negulescu et al, 1996

5. The [Ca2+]i rise is necessary for T cell activation
I. Pharmacological evidence
Chung et al, 1994

6. The [Ca2+]i rise is necessary for T cell activation
II. Genetic evidence
Le Diest et al, 1995

7. The [Ca2+]i rise (with PKC activation) is sufficient to induce TCR-responsive genes
Diehn et al, 2002

8. Duration and amplitude requirements for the Ca2+ signal
Dolmetsch et al, 1998
Negulescu et al, 1994

9. Generation of the Ca2+ signal by antigen recognition
I. IP3-induced Ca2+ release
Winslow et al, 2003
IP3
Imboden & Stobo, 1985

10. IP3-induced Ca2+ release is highly cooperative
Jurkat cells
IP3 receptors in planar lipid bilayer
Bezprozvanny et al, 1991

12. TCR engagement triggers “capacitative” (store-operated) Ca2+ entry in lymphocytes
Mason et al, 1991

13. TCR engagement stimulates Ca2+ entry via the CRAC channel
Premack et al, 1994
Zweifach and Lewis, 1993

15. CRAC channels are the sole Ca2+ entry pathway triggered through the TCR
mutagenize Ca
dipA
Jurkat
NFAT/dipA
survival X
Ionomycin + PdBU
Fanger et al, 1995
(Also see Partiseti et al, 1994; Feske et al, 2001)