00:01
The voltage -gated sodium channels consist of a long polypeptide chain comprised of about 1 ,840 amino acids.
00:19
Each of such molecules has four repeat domains, each containing six membrane spanning trans membrane alpha helix regions, and each of which the voltage sensor is located into four segments, which contain positively charged amino acid residues in every third.
00:38
Position.
00:40
Such four repeat domains are suggested to cluster together so as to give origin to a pore.
00:46
Such a pore is told to be closed whenever the membrane spanning voltage is set at the value lying between the activating threshold level and activation gate.
00:57
And as a result, the membrane undergoes depolarization.
01:01
This is when the threshold level of the molecule is suggested to rotate so that the configuration allows the sodium ions to flow unhampered through the pore.
01:09
Hence, inactivation is removed when the membrane potential of the cell repolarizes following the falling phase of the action potential, which in turn allows the channels to be activated again during the next action potential.
01:23
Gcprs are integral membrane proteins...