Saeij J P J, Boyle J P, Coller S, Taylor S, Sibley L D, Brooke-Powell E T, Ajioka J W, Boothroyd J C
Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Science. 2006 Dec 15;314(5806):1780-3. doi: 10.1126/science.1133690.
The majority of known Toxoplasma gondii isolates from Europe and North America belong to three clonal lines that differ dramatically in their virulence, depending on the host. To identify the responsible genes, we mapped virulence in F(1) progeny derived from crosses between type II and type III strains, which we introduced into mice. Five virulence (VIR) loci were thus identified, and for two of these, genetic complementation showed that a predicted protein kinase (ROP18 and ROP16, respectively) is the key molecule. Both are hypervariable rhoptry proteins that are secreted into the host cell upon invasion. These results suggest that secreted kinases unique to the Apicomplexa are crucial in the host-pathogen interaction.
欧洲和北美的大多数已知弓形虫分离株属于三个克隆系，根据宿主不同，它们的毒力差异很大。为了鉴定相关基因，我们在源自II型和III型菌株杂交产生的F(1)后代中绘制了毒力图谱，并将这些后代引入小鼠体内。由此鉴定出了五个毒力（VIR）位点，其中两个位点的基因互补表明，一种预测的蛋白激酶（分别为ROP18和ROP16）是关键分子。两者都是高变的棒状体蛋白，入侵时会分泌到宿主细胞中。这些结果表明，顶复门特有的分泌激酶在宿主-病原体相互作用中至关重要。
