Functional interaction of syntaxin and SNAP-25 with voltage-sensitive L- and N-type Ca2+ channels.

摘要: We have used an electrophysiological assay to investigate the functional interaction of syntaxin 1A and SNAP-25 with class C, L-type, B, N-type, voltage-sensitive calcium channels. Co-expression pore-forming subunits L- N-type channels in Xenopus oocytes generates a dramatic inhibition inward currents (>60%) modifies rate inactivation (tau) steady-state voltage dependence inactivation. Syntaxin 1-267, which lacks transmembrane region (TMR), 2 do not modify channel properties, suggesting that site resides predominantly TMR. significantly gating properties displays modest current amplitude. combined restore syntaxin-inhibited but reduced Hence, distinct putative 1A-SNAP-25 complex is apparent, consistent formation synaptosomal SNAP receptors (SNAREs) complex. The vivo reconstitution: (i) establishes proximity SNAREs channels; (ii) provides new insight into potential regulatory role for two controlling influx through N- L-type (iii) may suggest pivotal secretion process.