Immunoblots of hPEPT1 protein in the small
intestine, large intestine,
and kidney of wildtype (WT = mPept1+/+), Pept1 knockout (KO = mPept1–/–), and humanized PEPT1 (HU = mPept1–/–/hPEPT1+/–) mice (A), and mPEPT1 protein in the jejunum of the same genotypes
(B). Protein samples were separated by 10% SDS-PAGE, transferred onto
PVDF membranes, and incubated for 1.5 h with rabbit antihuman hPEPT111 (1:3000) or antimouse mPEPT112 (1:5000) antiserum, and a mouse monoclonal antibody for
β-actin (1:1000). The membranes were washed three times with
TBST and then incubated for 1 h with an appropriate secondary antibody
of IgG conjugated to horseradish peroxidase (1:3000). Caco-2 cells
served as positive and negative controls, respectively, for hPEPT1
and mPEPT1. Duo represents the duodenum, Jej the jejunum, Ile the
ileum, PC the proximal colon, DC the distal colon, and Kid the kidney.