Table 2. Suppressing KAT1 K⁺ Current in Xenopus Oocytes by VAMP721 Depends on the Longin Domain Residue Tyr-57.

	V1/2 (mV)	gmax (ms)	δ
KAT1	−126.7 ± 0.7	1.47 ± 0.01	−1.65 ± 0.04
KAT1+VAMP721Y57D	−128.5 ± 0.6
KAT1+VAMP723	−128.3 ± 0.6
KAT1+VAMP721	−139.6 ± 1.5*	0.57 ± 0.01
KAT1+VAMP721Y57A	−140.7 ± 1.4*
KAT1+VAMP723D57Y	−141.5 ± 1.6*

Parameter values are results of joint, nonlinear least-squares fitting of K⁺ currents in Figure 9. Fittings were carried out with the gating charge, δ, held in common across all data sets, and values for g_max were held to common values between groups of three data sets as indicated. Values for the voltage giving half-maximal conductance V_1/2 and conductance maximum g_max were allowed to vary between all of the data sets. Data are from seven or more separate experiments for each construct combination and are given as means ± se. Significance for V_1/2 as the difference from KAT1 expressed alone *P < 0.01.