Peirasmaki Dimitra, Ma'ayeh Showgy Y, Xu Feifei, Ferella Marcela, Campos Sara, Liu Jingyi, Svärd Staffan G
Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
Eukaryotic Single Cell Genomics Platform, Karolinska Institute, Science for Life Laboratory (SciLifeLab), Solna, Sweden.
Front Genet. 2020 Aug 18;11:913. doi: 10.3389/fgene.2020.00913. eCollection 2020.
colonizes the upper small intestine of humans and animals, causing the diarrheal disease giardiasis. This unicellular eukaryotic parasite is not invasive but it attaches to the surface of small intestinal epithelial cells (IECs), disrupting the epithelial barrier. Here, we used an model of the parasite's interaction with host IECs (differentiated Caco-2 cells) and RNA sequencing (RNAseq) to identify differentially expressed genes (DEGs) in , which might relate to the establishment of infection and disease induction. trophozoites interacted with differentiated Caco-2 cells for 1.5, 3, and 4.5 h and at each time point, 61, 89, and 148 parasite genes were up-regulated more than twofold, whereas 209, 265, and 313 parasite genes were down-regulated more than twofold. The most abundant DEGs encode hypothetical proteins and members of the High Cysteine Membrane Protein (HCMP) family. Among the up-regulated genes we also observed proteins associated with proteolysis, cellular redox balance, as well as lipid and nucleic acid metabolic pathways. In contrast, genes encoding kinases, regulators of the cell cycle and arginine metabolism and cytoskeletal proteins were down-regulated. Immunofluorescence imaging of selected, up-regulated HCMPs, using C-terminal HA-tagging, showed localization to the plasma membrane and peripheral vesicles (PVs). The expression of the HCMPs was affected by histone acetylation and free iron-levels. In fact, the latter was shown to regulate the expression of many putative giardial virulence factors in subsequent RNAseq experiments. We suggest that the plasma membrane localized and differentially expressed HCMPs play important roles during -host cell interactions.
它定殖于人类和动物的小肠上段,引发腹泻性疾病贾第虫病。这种单细胞真核寄生虫不具有侵袭性,但它附着于小肠上皮细胞(IECs)表面,破坏上皮屏障。在此,我们利用该寄生虫与宿主IECs(分化的Caco-2细胞)相互作用的模型以及RNA测序(RNAseq)来鉴定该寄生虫中差异表达基因(DEGs),这些基因可能与感染的建立和疾病诱导有关。贾第虫滋养体与分化的Caco-2细胞相互作用1.5、3和4.5小时,在每个时间点,分别有61、89和148个寄生虫基因上调超过两倍,而有209、265和313个寄生虫基因下调超过两倍。最丰富的DEGs编码假定蛋白和高半胱氨酸膜蛋白(HCMP)家族成员。在上调基因中,我们还观察到与蛋白水解、细胞氧化还原平衡以及脂质和核酸代谢途径相关的蛋白。相比之下,编码激酶、细胞周期调节因子、精氨酸代谢和细胞骨架蛋白的基因则下调。使用C末端HA标签对选定的上调HCMPs进行免疫荧光成像,结果显示其定位于质膜和外周囊泡(PVs)。HCMPs的表达受组蛋白乙酰化和游离铁水平的影响。事实上,在随后的RNAseq实验中,后者被证明可调节许多假定的贾第虫毒力因子的表达。我们认为定位于质膜且差异表达的HCMPs在寄生虫与宿主细胞相互作用过程中发挥重要作用。