Figure 3. HA-mGlu₇-I154T receptors exhibit reduced surface trafficking in HEK293A cells and are degraded by the proteasome.

(A) Western blot of total protein lysate from HEK293A cells expressing HA-mGlu₇-WT or HA-mGlu₇-I154T. (B) Quantification of different immunoreactive bands representing mGlu₇. (C) Quantification of dimer-to-monomer ratio. For B and C, n = 3 biological replicates. Two-tailed Student’s t tests. **P < 0.01, ***P < 0.001. (D) Western blot in the presence or absence of PNGase F treatment. (E) Western blot in the presence or absence of EndoH treatment. For panels D and E, open arrows indicate bands resulting from deglycosylation. n = 3 independent experiments. (F) Western blot of cell lysates after a 4-hour treatment with 10 μM MG-132 or vehicle (DMSO). (G and H) Quantification of mGlu₇ dimer (G) and monomer (H) bands after MG-132 treatment. n = 3 independent experiments. Two-way ANOVA with Sidak’s multiple comparisons. *P < 0.05, **P < 0.01. ns, not significant; mGlu₇, metabotropic glutamate receptor subtype 7.