In the brain, the significant induction of Arg1 and its associated metabolic enzymes during the later stages of infection, along with the gradual downregulation of Nos2 expression and increased expression of the arginine transporters Slc7A2 and Slc25A15 (Figure 2(C)), suggests enhanced arginine uptake, potentially compensating for systemic L-arginine depletion. The gene discussed is NOS2; the disease is infection.