Human nACh d -- Glu 59

Species Original Mutated to Mutation
Human Glu 59 Lys

E59K

Rat Equivalent Asp 59    
Mouse Equivalent Asp 59    

hGlu59Lys

When this mutation in both adult and fetal ACh receptors, surface binding was reduced to around 60%. When the open probability of the mutant receptors was tested using concentrations between 10 and 500 mM ACh, the activity occurred in clusters of openings from individual channels separated by longer closing periods. It was shown that the open probability for the mutant was lower than that of the wildtype. The Ec50 for the mutant was 58.4 mM ACh, and for the wildtype was 14.2 mM ACh. Both adult and fetal receptors with the E59K mutation are likely to have fewer and shorter channel activations.

This mutation has been correlated with myasthenic syndrome.

Brownlow S, Webster R, Croxen R, Brydson M, Neville B, Lin JP, Vincent A, Newsom-Davis J, Beeson D (2001) Acetylcholine Receptor d Subunit Mutations Underlie a Fast-Channel Myasthenic Syndrom and Arthrogryposis Multiplex Congenita. The Journal of Clinical Investigation 108(1):125-130

 

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