Table_2_Using scRNA-seq to Identify Transcriptional Variation in the Malaria Parasite Ookinete Stage.xlsx

The crossing of the mosquito midgut epithelium by the malaria parasite motile ookinete form represents the most extreme population bottleneck in the parasite life cycle and is a prime target for transmission blocking strategies. However, we have little understanding of the clonal variation that exists in a population of ookinetes in the vector, partially because the parasites are difficult to access and are found in low numbers. Within a vector, variation may result as a response to specific environmental cues or may exist independent of those cues as a potential bet-hedging strategy. Here we use single-cell RNA-seq to profile transcriptional variation in Plasmodium berghei ookinetes across different vector species, and between and within individual midguts. We then compare our results to low-input transcriptomes from individual Anopheles coluzzii midguts infected with the human malaria parasite Plasmodium falciparum. Although the vast majority of transcriptional changes in ookinetes are driven by development, we have identified candidate genes that may be responding to environmental cues or are clonally variant within a population. Our results illustrate the value of single-cell and low-input technologies in understanding clonal variation of parasite populations.

疟原虫运动型动合子（ookinete）穿过蚊虫中肠上皮（mosquito midgut epithelium），是疟原虫生命周期中最为严苛的种群瓶颈（population bottleneck）环节，同时也是传播阻断策略（transmission blocking strategies）的核心靶标。然而，学界对蚊媒种群内动合子的克隆变异（clonal variation）认知仍较为匮乏，这在一定程度上源于疟原虫样本难以获取且丰度极低。在蚊媒体内，此类变异既可能是对特定环境信号的响应结果，也可能作为一种潜在的套期保值策略（bet-hedging strategy）独立于环境信号存在。本研究利用单细胞RNA测序（single-cell RNA-seq）技术，对不同蚊媒物种、单个蚊中肠之间以及单个蚊中肠内部的伯氏疟原虫（Plasmodium berghei）动合子的转录变异特征进行解析。随后，我们将研究结果与感染人类疟原虫恶性疟原虫（Plasmodium falciparum）的科卢兹按蚊（Anopheles coluzzii）单个中肠的低起始量转录组数据进行了对比分析。尽管动合子的绝大多数转录变化由发育进程驱动，但我们已鉴定出若干候选基因，这些基因或响应环境信号，或在种群内呈现克隆变异特征。本研究结果证实了单细胞及低起始量技术在解析寄生虫种群克隆变异方面的应用价值。