PCK2 and infection: In I. scapularis ISE6 cells, A. phagocytophilum infection affects protein processing in the endoplasmic reticulum (ER) and glucose metabolic pathways by lowering protein levels of phosphoenolpyruvate carboxykinase (PEPCK), mitogen-activated protein kinase (MKK), and apoptosis signal-regulating kinase 1 (ASK1), resulting in the inhibition of tick cell apoptosis in order to increase pathogen infection [50].