Abstract: Objective To establish a method to relatively quantify the expression of ompT and the gene of APEC strain E058 in vivo. Methods Two-step real time quantitative RT-PCRs (qRT-PCR) of ompT and gapA were developed based on SYBR Green I, respectively. In these qRT-PCRs, ompT was identified as the target gene and gapA as internal reference, and two standard curves were established using a series dilution of cDNA synthesized from the RNA of APEC E058 grown statically to exponential phase in rich medium. Results qRT-PCR of ompT was established. In chicken challenge model, the expressions of ompT in APEC E058 were up-regulated 6.69-fold compared to that of APEC E058 grown statically to exponential phase in rich medium. Conclusion The established qRT-PCR was reliable for the expression analysis of ompT.

Key words: SYBR GreenI, qRT-PCR, ompT, expression