Differential gene expression in ap2-g and ap2-g2 mutants of Plasmodium berghei

Commitment to and completion of sexual development are essential for malaria parasites to be transmitted through mosquitoes. The molecular mechanism(s) responsible for these processes however, remain largely unknown. We have identified two transcription factors (both belonging to the AP2 family) essential for gametocytogenesis. AP2-G mutants are characterised by a complete inability to produce gametocytes. In AP2-G2 mutants the gametocytaemia is very significantly reduced but not completely abolished. We have performed the microarray experiments in order to cokmpare the transcriptomes of these mutantnts to the WT parasites and between each other. As P.berghei parasites are characterised by asynchronous development in the rodent host, the different stage composition of the sample would impact the analysis. Therefore parasites were harvested and matured in in vitro to the schizont stage Pairwaise comparison between the mutants and parental line was performed. 3 biological replicates of each condition were used.

疟原虫对有性发育的启动与完成，是其经由蚊虫传播的必要前提。然而，介导这两个过程的分子机制目前仍知之甚少。我们已鉴定出两个隶属于AP2家族（AP2 family）的转录因子，其对疟原虫配子体形成（gametocytogenesis）不可或缺：AP2-G突变体完全丧失配子体产生能力；AP2-G2突变体的配子体血症水平虽显著降低，但并未完全消除。为对比上述突变体与野生型（Wild Type，WT）疟原虫的转录组，以及各突变体间的转录组差异，我们开展了微阵列（microarray）实验。鉴于伯氏疟原虫（P.berghei）在啮齿类宿主内的发育具有异步性，样本中不同发育阶段的比例会干扰分析结果。因此，我们将疟原虫体外（in vitro）培养至裂殖体（schizont）阶段后再行收集，并对各突变体与其亲本株开展了两两比较分析。每个实验条件均设置3次生物学重复。