Table 1.
Notation and descriptions for the D2R mutants of the possible phosphorylation sites in the intracellular regions
| D2R mutants | Description | Characteristics |
|---|---|---|
| 1 | T67V, T68V, T69V | Expression level is decreased to about 50% of WT |
| 2 | T134V | |
| 3 | T144V, S147A, S148Aa | |
| 4 | T225Va, S228A, S229Ab | DA-induced internalization is reduced |
| 5 | S256A, S257A, T258V, S259A | Possible casein kinase II site |
| 6 | T264V, S267A | |
| 7 | S272A, T277V | |
| 8 | S282A | S282C is associated with schizophrenia (46) |
| 9 | S288A, T289V, S292A | |
| 10 | T316V | |
| 11 | T322V, T324V, S325Aa | |
| 12 | T328V, S330Aa | |
| 13 | S335Ab | |
| 14 | T343Vb | |
| IC2 | T134V, T144V, S147A, S148A | DA-induced internalization is reduced |
| DA-induced desensitization is induced | ||
| IC3 | T225V, S228A, S229A, S256A, S257A, T258V, S259A, T264V, S267A, S272A, T277V, S282A, S288A, T289V, S292A, T316V, T322V, T324V, S325A, T328V, S330A, S335A, T343V | DA-induced internalization is moderately reduced |
| DA-induced desensitization is moderately induced | ||
| IC2/3 | IC2 + IC3 | DA-induced phosphorylation was abolished |
| IC123 | IC23 + T67V, T68V, T69V |
The values represent the position of the amino acid residues starting from the N-terminal end, Met1.
a
These regions contain the putative phosphorylation sites for protein kinase C.
b
These regions contain the putative phosphorylation sites for protein kinase A.