Our observation that higher rAAV-shNCLX infection rates resulted in lower Nclx RNA levels and diminished viability compared with a lower infection rate (Fig. 4) nonetheless supports the idea that degree of NCLX dysregulation may be a key defining factor for determining how a given cell or population of cells will respond to synaptic activity or excitotoxic challenge. This evidence concerns the gene SLC8B1 and infection.