Evaluation of the transgene expression in ELR1/eCT1 mice. (A) The transmission of eCT1 and ELR1 in six transgenic founder mice (numbers 1–6) and eight F5 progeny mice (T13-T20) was determined by PCR. DNA was extracted from the tails of the indicated mice, and the integration of the ELR1 and eCT1 genes was detected by PCR with primer pairs specific for these two equine genes. N: negative control using wild-type mouse tail DNA; P: positive control using the ELR1 or eCT1 recombinant plasmid. (B) and (C) The ELR1 and eCT1 RNA levels in six organs (intestine, spleen, lymph nodes, kidney, lung and liver) from ELR1/eCT1 mice and wild-type mice (eight mice/group) were quantified by real-time RT-PCR. Statistical analyses were performed using SAS version 9.0 (SAS Institute Inc., Cary, NC). Significant differences between the organs in the groups of ELR1/eCT1 mice were determined using Student’s t test. *, P < 0.05; **, P < 0.01. (D) The expression of the ELR1 and eCT1 transgenes in the organs of the F5 progeny mice was detected by Western blot analysis. The lysates from the organs of the F5 progeny mice and wild-type mice were prepared, and equal amounts of protein (50 μg protein/sample) were used for the analysis. A specific monoclonal antibody was used to detect ELR1, and a rabbit antiserum was used to detect eCT1. P: positive control using lysates from 293T cells transfected with either the ELR1 or eCT1 recombinant plasmid.