Which of the following changes is most likely to convert a l

Which of the following changes is most likely to convert a ligand-gated sodium channel into a ligand-gated potassium channel?

a)A change in the primary amino acid sequence so that the protein is more positively charged

b)A mutation in the ligand binding site so that K+ can induce the opening of the channel

c)A mutation that changes the selectivity filter of the channel

d)A mutation that alters the subcellular location of the channel

e)None of the above is likely to change the specificity of the sodium channel

Solution

Answer:-

c) A mutation that changes the selectively filter of the channel.

Ligand-gated Sodium chanel being a smaller than a Pottasium it would be able to interact with oxygen atoms on once side of the chanel only. removal of the waters of hudration from sodium for entry into the chanel then pottasium selectively filter is required to stabilise its ION-conducting corformation.if Sodium is substituted for Pottasium in the medium the selectively filter undegoes a corformation changes.