Figure 3.

Diagram illustrating the pentameric symmetrical model and predicted hybrid nAcChoR diversity. The model assumes five equivalent subunits and results in eight different combinations, a number equivalent to the identified receptor populations (Table 1). The algorithm calculating the number of possible permutations in a symmetrical model, when the number of receptor subunits n is a prime number, is the following: {[(2ⁿ − 2)/n] + 2}. White circles represent WT α₇ subunits; gray circles, L247T α₇ subunits. a and b hypothetically refer to L247T mutant-like and WT-like nAcChoRs, respectively, identified in Table 1.