Lv Bo, Zhuo Jun-Zhe, Peng Yuan-de, Wang Zhi
College of Life Science, Hunan Normal University, Changsha, 410081, China.
College of Bioscience and Biotechnology, Hunan Agriculture University, Changsha, 410128, Hunan, China.
Environ Sci Pollut Res Int. 2022 May;29(22):32832-32844. doi: 10.1007/s11356-022-18548-w. Epub 2022 Jan 12.
Cadmium (Cd) pollution is a serious heavy metal pollution in paddy fields, but its effect and underlying mechanism on soil arthropod overwintering and cold resistance are still unclear. In the present study, adult females of the wolf spider Pirata subpiraticus exposed to Cd stress underwent a simulated temperature process (25℃ → 16℃ → 8℃ → 4℃). The mortality rate and content of nutrients in the Cd-treated spiders were dramatically elevated after low-temperature treatment compared to those in the Cd-free control spiders under the same temperature condition. To uncover the putative modulatory mechanism of Cd on cold tolerance in P. subpiraticus, we employed an in-depth RNA sequencing analysis and yielded a total of 888 differentially expressed genes (DEGs). Besides, we characterized genes that participate in multiple cryoprotectant syntheses, including arginine, cysteine, glucose, glycerol, heat shock protein, and mannose. The enrichment analyses found that most of the DEGs involved in biological processes and pathways were related to carbohydrate, lipid, and protein metabolism. Notably, ten Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, such as starch and sucrose metabolism, arachidonic acid metabolism, amino acid metabolism, mineral absorption, and vitamin digestion and absorption, were distinctively enriched with downregulated genes. Meanwhile, we also identified that seven DEGs might inhibit the KEGG pathway of ovarian steroidogenesis and potentially cripple ovarian function and fecundity in the spider. The decreased egg sac weight, number of hatched spiderlings, and vitellin concentration further supported the view that Cd exposure vitiates the overwintering spider's fecundity. Collectively, the comparative analysis provides a novel perspective regarding the survival response and fecundity on the cold tolerance of spiders under Cd stress and offers a profound insight for evaluating Cd-induced toxicity on overwintering arthropods.
镉（Cd）污染是稻田中一种严重的重金属污染，但其对土壤节肢动物越冬和抗寒能力的影响及潜在机制仍不清楚。在本研究中，将暴露于镉胁迫下的拟水狼蛛成年雌蛛进行模拟温度处理（25℃→16℃→8℃→4℃）。与相同温度条件下未接触镉的对照蜘蛛相比，低温处理后镉处理蜘蛛的死亡率和营养物质含量显著升高。为了揭示镉对拟水狼蛛耐寒性的假定调节机制，我们进行了深入的RNA测序分析，共获得888个差异表达基因（DEGs）。此外，我们鉴定了参与多种抗冻剂合成的基因，包括精氨酸、半胱氨酸、葡萄糖、甘油、热休克蛋白和甘露糖。富集分析发现，大多数参与生物过程和途径的DEGs与碳水化合物、脂质和蛋白质代谢有关。值得注意的是，十个京都基因与基因组百科全书（KEGG）途径，如淀粉和蔗糖代谢、花生四烯酸代谢、氨基酸代谢、矿物质吸收以及维生素消化和吸收，显著富集了下调基因。同时，我们还确定了七个DEGs可能抑制卵巢类固醇生成的KEGG途径，并可能削弱蜘蛛的卵巢功能和繁殖力。卵囊重量、孵化出的幼蛛数量和卵黄蛋白浓度的降低进一步支持了镉暴露会损害越冬蜘蛛繁殖力的观点。总的来说，比较分析为镉胁迫下蜘蛛耐寒性的生存反应和繁殖力提供了一个新的视角，并为评估镉对越冬节肢动物的毒性提供了深刻的见解。
