关键词: 遗传学, 致密颗粒抗原1, 聚合酶链反应, 克隆, 分子, 变异(遗传学)

Abstract: Objective To construt a recombinant eukaryotic expressing plasmid containing dense granules antigen (GRA1) gene of Toxoplasma gondii. Methods A pair of primers were designed for PCR according to the known sequence of GRA1 gene.The full fragment of GRA1 gene obtained by PCR amplification from genomic DNA of RH strain of Toxoplasma gondii was cloned into plasmid pcDNA3 orientatedly.The constructed recombinant plasmid pcDNA3-GRA1 was transferred into E.coli DH5α.The transformatants were screened and identified by restriction endonuclease digestion and PCR. The nucleotide sequences of the cloned genes were determined. Results A 775 bp GRA1 gene PCR product was obtained from genomic DNA of the RH strain of Toxoplasma gondii,in which a 135 bp inserted sequence was found.Therefore the PCR product was longer than expected (628 bp).The frameshift mutation for GRA1 gene resulted from the insertion of exogenous sequence. Conclusion The inserted variation of GRA1 gene of the RH strain of Toxoplasma gondii is reported and its recombinant expressing plasmid is construted.

Key words: genetics, GRA1, PCR, cloning, molecalar, variation (genetics)