Different effects depending on the B. burgdorferi strain: Bre-13 infection causes upregulation of GST in tick salivary glands; downregulation of GST in B31 infection, upregulation of protein disulfide isomerase in PBi, B31, and N40 infection, and upregulation of heme lipoprotein precursor in PBi and B-31 infection. This evidence concerns the gene P4HB and infection.