Abstract: To determine the transfection efficiency about PBase to piggyBac transposon in transfecting to Toxoplasma gondii, T. gondii RH strain tachyzoites were transfected with plasmid PB-Toxo-RFP which was expressed piggyBac transposon with a red fluorescent protein and Toxo-PBase plasmid which is a transposable enzyme. T. gondii tachyzoites were transfected with PB-Toxo-RFP plasmid alone as control group. The expression of red fluorescent protein was detected by flow cytometry at 24 h after transfection. The transposition efficiency in PB-Toxo-RFP+Toxo-PBase group and PB-Toxo-RFP group was 73% and 43%, respecitvely（P<0.01）. It suggests that the PBase transposase can improve the transfection efficiency of piggyBac transposon in T. gondii tachyzoites.

Key words: piggyBac transposon, Transposase, Transposition efficiency, Toxoplasma gondii