AKT1 and lymphopenia: Rats:Normal T cell development; reduced T cell export; peripheral T lymphopenia; Survival defects in naïve resting T cells; normal B and NK cells; T cell-mediated autoimmunity dependent on the genetic background; Normal life span; spontaneous activation of the AKT signaling pathwayMice:Deficiency in T, B and NK cells; survival defects in lymphocytes; exhaustion of HSC; hepatic extramedullary hematopoiesis; reduced life span; spontaneous activation of AKT signalingIn another independent knockout mouse line, no defect was observed