Abstract
The voltage sensitive N-type calcium channel interacts functionally and biochemically with synaptotagmin (p65). N-type channel interaction with p65 is demonstrated in the Xenopus oocyte expression system, where p65 alters the steady state voltage inactivation of the N-channel, and fully restores the syntaxin-modified current amplitude and inactivation kinetics in a calcium dependent manner. In agreement with the functional results, GST-p65 fusion protein binds to a cytosolic region, amino acids 710-1090 of the N-type channel (N-loop710-1090). The results of the combined approach provide a functional and biochemical basis for proposing that p65 interaction with the N-type channel brings p65 into a close association with a syntaxin-coupled channel. In turn, calcium entry through the liberated channel initiates fusion of the primed vesicles with the cell membrane at a short distance from the site of calcium entry.
Original language | English |
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Pages (from-to) | 203-207 |
Number of pages | 5 |
Journal | FEBS Letters |
Volume | 404 |
Issue number | 2-3 |
DOIs | |
State | Published - 10 Mar 1997 |
Externally published | Yes |
Keywords
- N-type calcium channel
- SNAP-25
- Synaptotagmin
- Syntaxin
- Transmitter release