. Author manuscript; available in PMC: 2009 Aug 31.

Published in final edited form as: Cell Calcium. 2007 May 7;42(2):133–144. doi: 10.1016/j.ceca.2007.03.002

Table 1.

Comparison of CRAC current biophysical properties

Property	Native T cell CRAC [7,9–11,53–55]	Native S2 CRAC [26,33]	Stim + Orai [33,48]	Stim + E180D Orai [48]
Store dependence	Yes	Yes	Yes	Yes
Inactivation by:
Store refilling	Yes	Yes	Not tested	Not tested
Local [Ca²⁺]_i	Yes	Yes	Yes	Yes
Run-down	Yes	Yes	Yes	Yes
Fast inactivation (100 ms time scale)	Yes	No	No	No
Calcium selectivity	Yes	Yes	Yes	No
Permeant divalent cations	Ca²⁺ > Ba²⁺ > Sr²⁺» Mg²⁺	Ba²⁺ > Ca²⁺ > Sr²⁺ » Mg²⁺	Ca²⁺ ∼ Sr²⁺ ∼Ba²⁺ » Mg²⁺	Negligible
Unitary channel conductance in 20 mM Ca²⁺	21 fS	36 fS	Not tested	N/A
Monovalent current in zero divalent	Yes	Yes	Yes	Yes
Monovalent cation selectivity, P_Cs/P_Na	Na⁺ > Cs⁺, 0.09–0.13	Na⁺ > Cs⁺, 0.17	Na⁺ > Cs⁺, 0.13	Na⁺ ∼ Cs⁺, 0.71
Depotentiation	Yes	Yes	Yes	No
Pharmacology:
Gd³⁺ or La³⁺	nM (Gd³⁺), reversible	nM (Gd³⁺), reversible	nM (Gd³⁺), reversible	nM (Gd³⁺), reversible
SKF 96365	μM, partially reversible	μM, partially reversible	Not tested	Not tested
2-APB	Low μM – potentiation; high μM – inhibition	Low μM – potentiation; high μM – inhibition	Low μM – potentiation; high μM – inhibition	Low and high μM – complex behavior (potentiation and inhibition phases)

Results are summarized from the indicated references.