Meanwhile, an increasing body of evidence suggests that Homer protein homolog 1 (Homer1)-metabotropic glutamate receptor 5 (mGluR5) and downstream mammalian target of rapamycin (mTOR) signaling pathways affect the expression of proteins involved in the modulation of synaptic plasticity that may drive the pathophysiology of depression. The gene discussed is HOMER1; the disease is depressive disorder.