Laboratory of Medical Zoology, Department of Medicine, Mie University, Tsu, Japan.
Department of Molecular Protozoology, Research Institute for Microbial Diseases, Osaka University, Suita, Japan.
PLoS Pathog. 2023 Feb 13;19(2):e1010890. doi: 10.1371/journal.ppat.1010890. eCollection 2023 Feb.
Gametocyte development is a critical step in the life cycle of Plasmodium. Despite the number of studies on gametocyte development that have been conducted, the molecular mechanisms regulating this process remain to be fully understood. This study investigates the functional roles of two female-specific transcriptional regulators, PbAP2-FG2 and PbAP2R-2, in P. berghei. Knockout of pbap2-fg2 or pbap2r-2 impairs female gametocyte development, resulting in developmental arrest during ookinete development. ChIP-seq analyses of these two factors indicated their colocalization on the genome, suggesting that they function as a complex. These analyses also revealed that their target genes contained a variety of genes, including both male and female-enriched genes. Moreover, differential expression analyses showed that these target genes were upregulated through the disruption of pbap2-fg2 or pbap2r-2, indicating that these two factors function as a transcriptional repressor complex in female gametocytes. Formation of a complex between PbAP2-FG2 and PbAP2R-2 was confirmed by RIME, a method that combines ChIP and MS analysis. In addition, the analysis identified a chromatin regulator PbMORC as an interaction partner of PbAP2-FG2. Comparative target analysis between PbAP2-FG2 and PbAP2-G demonstrated a significant overlap between their target genes, suggesting that repression of early gametocyte genes activated by PbAP2-G is one of the key roles for this female transcriptional repressor complex. Our results indicate that the PbAP2-FG2-PbAP2R-2 complex-mediated repression of the target genes supports the female differentiation from early gametocytes.
配子体发育是疟原虫生命周期中的一个关键步骤。尽管已经有许多关于配子体发育的研究，但调控这一过程的分子机制仍有待充分理解。本研究调查了两个雌性特异性转录调节剂，PbAP2-FG2 和 PbAP2R-2，在 P. berghei 中的功能作用。敲除 pbap2-fg2 或 pbap2r-2 会损害雌性配子体发育，导致在动合子发育过程中发育停滞。这两个因子的 ChIP-seq 分析表明它们在基因组上的共定位，表明它们作为一个复合物发挥作用。这些分析还表明，它们的靶基因包含各种基因，包括雄性和雌性富集基因。此外，差异表达分析表明，通过破坏 pbap2-fg2 或 pbap2r-2，这些靶基因的表达上调，表明这两个因子作为雌性配子体中的转录抑制复合物发挥作用。RIME（一种结合 ChIP 和 MS 分析的方法）证实了 PbAP2-FG2 和 PbAP2R-2 之间形成复合物。此外，该分析还确定了一个染色质调节剂 PbMORC 作为 PbAP2-FG2 的相互作用伙伴。PbAP2-FG2 和 PbAP2-G 之间的比较靶分析表明，它们的靶基因之间存在显著重叠，这表明 PbAP2-G 激活的早期配子体基因的抑制是该雌性转录抑制复合物的关键作用之一。我们的研究结果表明，PbAP2-FG2-PbAP2R-2 复合物介导的靶基因抑制支持早期配子体从雌性分化。
