GPR75 and obesity due to melanocortin 4 receptor deficiency: In-depth exploration of GPR75’s oligomerization dynamics and intracellular localization will not only reveal novel mechanisms by which this receptor regulates cardiovascular homeostasis, energy metabolism, and synaptic plasticity but also establish a theoretical foundation for developing biased drugs targeting GPR75, which is of significant value in treating major diseases, such as obesity, Alzheimer’s disease, and cancer.