Department of Animal Biosciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Umeå Plant Science Centre (UPSC), Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden.
PLoS One. 2024 Feb 15;19(2):e0298039. doi: 10.1371/journal.pone.0298039. eCollection 2024.
Anthelmintic resistance in equine parasite Parascaris univalens, compromises ivermectin (IVM) effectiveness and necessitates an in-depth understanding of its resistance mechanisms. Most research, primarily focused on holistic gene expression analyses, may overlook vital tissue-specific responses and often limit the scope of novel genes. This study leveraged gene co-expression network analysis to elucidate tissue-specific transcriptional responses and to identify core genes implicated in the IVM response in P. univalens. Adult worms (n = 28) were exposed to 10-11 M and 10-9 M IVM in vitro for 24 hours. RNA-sequencing examined transcriptional changes in the anterior end and intestine. Differential expression analysis revealed pronounced tissue differences, with the intestine exhibiting substantially more IVM-induced transcriptional activity. Gene co-expression network analysis identified seven modules significantly associated with the response to IVM. Within these, 219 core genes were detected, largely expressed in the intestinal tissue and spanning diverse biological processes with unspecific patterns. After 10-11 M IVM, intestinal tissue core genes showed transcriptional suppression, cell cycle inhibition, and ribosomal alterations. Interestingly, genes PgR028_g047 (sorb-1), PgB01_g200 (gmap-1) and PgR046_g017 (col-37 & col-102) switched from downregulation at 10-11 M to upregulation at 10-9 M IVM. The 10-9 M concentration induced expression of cuticle and membrane integrity core genes in the intestinal tissue. No clear core gene patterns were visible in the anterior end after 10-11 M IVM. However, after 10-9 M IVM, the anterior end mostly displayed downregulation, indicating disrupted transcriptional regulation. One interesting finding was the non-modular calcium-signaling gene, PgR047_g066 (gegf-1), which uniquely connected 71 genes across four modules. These genes were enriched for transmembrane signaling activity, suggesting that PgR047_g066 (gegf-1) could have a key signaling role. By unveiling tissue-specific expression patterns and highlighting biological processes through unbiased core gene detection, this study reveals intricate IVM responses in P. univalens. These findings suggest alternative drug uptake of IVM and can guide functional validations to further IVM resistance mechanism understanding.
马属寄生虫副蛔虫对驱虫药伊维菌素（IVM）的耐药性，降低了其有效性，因此需要深入了解其耐药机制。大多数研究主要集中在整体基因表达分析上，可能忽略了重要的组织特异性反应，而且往往限制了新基因的研究范围。本研究利用基因共表达网络分析阐明了组织特异性转录反应，并鉴定了副蛔虫对 IVM 反应中涉及的核心基因。将 28 条成虫暴露于 10-11 M 和 10-9 M 的 IVM 体外 24 小时。通过 RNA 测序检查了前肠和肠组织的转录变化。差异表达分析显示出明显的组织差异，肠组织表现出更多的 IVM 诱导转录活性。基因共表达网络分析确定了七个与 IVM 反应显著相关的模块。在这些模块中，检测到 219 个核心基因，这些基因主要在肠组织中表达，并跨越了各种具有非特异性模式的生物学过程。在 10-11 M IVM 后，肠组织核心基因表现出转录抑制、细胞周期抑制和核糖体改变。有趣的是，PgR028_g047（sorb-1）、PgB01_g200（gmap-1）和 PgR046_g017（col-37 和 col-102）基因在 10-11 M IVM 时下调，在 10-9 M IVM 时上调。10-9 M 浓度诱导肠组织中角质层和膜完整性核心基因的表达。在 10-11 M IVM 后，前肠中没有明显的核心基因模式。然而，在 10-9 M IVM 后，前肠主要表现为下调，表明转录调控受到干扰。一个有趣的发现是无模块钙信号基因 PgR047_g066（gegf-1），它独特地连接了四个模块中的 71 个基因。这些基因富含跨膜信号活性，表明 PgR047_g066（gegf-1）可能具有关键的信号作用。本研究通过揭示组织特异性表达模式和突出通过无偏核心基因检测的生物过程，揭示了副蛔虫中复杂的 IVM 反应。这些发现表明 IVM 的替代药物摄取方式，并可以指导功能验证，以进一步了解 IVM 耐药机制。
