Comparative analysis of cadmium-induced toxicity and survival responses in the wolf spider Pirata subpiraticus under low-temperature treatment

Integrated transcriptome and metabolomic analyses uncover the mechanism of cadmium-caused mouse spermatogonia apoptosis via inducing endoplasmic reticulum stress

Cadmium (Cd) is a well-recognized male reproductive toxicant that can cause testicular germ cell apoptosis. However, the underlying mechanism needs investigation. CG-1 mouse spermatogonia (spg) cells were treated with 20 μM cadmium chloride (CdCl2) for 24 h. Cell apoptosis was measured, and the expressions of key genes and protein biomarkers involved in endoplasmic reticulum (ER) stress were detected, respectively. Untargeted metabolomics was performed to identify different metabolites, and transcriptome analysis was conducted to screen differentially expressed genes (DEGs). Our results indicated that CdCl2 exposure caused cell apoptosis, and DEGs were involved in several apoptosis-related pathways. Moreover, CdCl2 exposure apparently increased the mRNA and protein expressions levels of both GRP78 and ATF6α, disrupting the expression of various metabolites, particularly amino acids. Conclusively, our study reveals the pathway of CdCl2 toxicity on mouse spg, providing a deep understanding of CdCl2-induced testicular toxicity.

Integrated transcriptome and metabolome analysis reveals molecular responses of spider to single and combined high temperature and drought stress

High temperature and drought are abiotic stresses restricting many arthropods' survival and growth. Wolf spiders are poikilothermic arthropods that are vital in managing insects and pests. Nonetheless, investigating changes in spiders under temperature and drought stress are limited, especially at the molecular and gene expression levels. The study found that the combined effects of high temperature and drought stress significantly reduced survival rates and raised superoxide dismutase and malondialdehyde levels in the wolf spider Pardosa pseudoannulata. An integrated transcriptome and metabolome analysis showed that differentially expressed genes and metabolites were highly enriched in pathways involved in the proteolysis and oxidation-reduction process. The gene expression profiles displayed that heat shock protein (HSP) families (i.e., small heat shock protein, HSP70, HSP90, and HSP beta protein) were up-regulated under temperature and/or drought stresses. Additionally, a conjoint analysis revealed that under the combined stress, several important enzymes, including maltase-glucoamylase, glycerol-6-phosphate transporter, alanine-glyoxylate transaminase, and prostaglandin-H2 D-isomerase, were altered, affecting the metabolism of starch, sucrose, amino acids, and arachidonic acid. The protein interaction network further confirmed that under the combined stress, metabolic processes, peptide metabolic processes, and ATP generation from ADP were up-regulated, indicating that spiders could accelerate the metabolism of carbohydrates and proteins to combat stress and maintain homeostasis. Overall, this work showed that exposure to a combination of pressures might cause distinct defensive reactions in spiders and offered novel perspectives to research the molecular underpinnings of spider adaptation to a changing climate.

Integrative analysis uncovers response mechanism of Pirata subpiraticus to chronic cadmium stress

Soil cadmium (Cd) pollution is global environmental pollution and adversely affects paddy field organisms. Wolf spider grants a new insight to evaluate the toxicity triggered by Cd, yet the impact of chronic Cd exposure on the spider and its molecular mechanism remains unclear. The present study found that the wolf spider Pirata subpiraticus fed with Cd-accumulated flies for 5 weeks presented lower catalase, peroxidase, and acetylcholinesterase activities and higher malonaldehyde content than the control spiders (p < 0.05). An in-depth transcriptomic analysis yielded a total of 5995 differentially expressed genes (DEGs, with 3857 up-regulated and 2138 down-regulated genes) from the comparison, and 19 DEGs encoding three enzymatic indicators were down-regulated. Further enrichment analysis indicated that Cd stress could inhibit the expression of cuticle and chitin-encoding genes via the down-regulation of several key enzymes, such as chitin synthase, glutamine-fructose-6-phosphate transaminase, and chitinase. In addition, our findings suggested that hedgehog and FoxO signaling pathways might play an essential role in regulating survival, cell cycle, and autophagy process in spiders, which were primarily down-regulated under Cd stress. An intensely interactive network displayed that Cd exposure could repress key biological processes in P. subpiraticus, particularly peptide metabolic process and peptide biosynthetic process. To sum up, this integrative investigation confirmed an effective bioindicator for assessing Cd-induced toxicity; provided a mass of genes, proteins, and enzymes for further validation; and granted novel perspectives to uncover the molecular responses of spiders to Cd pollution.

Transcriptomic analysis of cadmium toxicity and molecular response in the spiderling of Pirata subpiraticus

Cadmium (Cd) is a kind of toxic heavy metal widely distributed in the environment, posing life-threatening challenges to organisms. The paddy field spider is a natural enemy of pests and an essential component of rice biodiversity. Nonetheless, the effects of Cd stress on the postembryonic development of spiders and its detailed mechanism remain to be investigated. In the present study, we found that Cd stress posed adverse impacts on the growth indicators (e.g., carapace length, development duration, and survival rate) and increased the levels of three antioxidants (i.e., superoxide dismutase, glutathione S-transferase, and glutathione peroxidase) in the spiderlings of Pirata subpiraticus. An in-depth transcriptome analysis was employed in the study, and the results displayed that differentially expressed genes (DEGs) involved in postembryonic morphogenesis, development involved in symbiotic interaction, postembryonic development, and growth were distinctively altered under Cd stress. Further enrichment analysis showed that Cd exposure could activate the apoptosis pathway in the spider via the up-regulation of several key factors, including caspase-10, α-tubulin, actin, etc. In addition, we demonstrated that the increased level of glutathione-related enzymes in spiderlings was caused by the activation of glutathione metabolic pathway. The altered hedgehog signaling pathway might affect cell proliferation, tissue patterning, and development of spiderlings. Further protein interaction network displayed that Cd stress could affect multiple biological processes in spiderlings, particularly cellular response to stimulus and system development. To sum up, this study can provide multi-level perspectives to understand the toxicity of Cd on the growth and development of spiders.

Comparative analysis unveils the cadmium-induced reproductive toxicity on the testes of Pardosa pseudoannulata

Cadmium (Cd) pollution is one of the most serious heavy metal pollutions in the world, which has been demonstrated to cause different toxicities to living organisms. Cd has been widely suggested to cause reproductive toxicity to vertebrates, yet its reproductive toxicity to invertebrates is not comprehensive. In this study, the wolf spider Pardosa pseudoannulata was used as a bioindicator to evaluate the male reproductive toxicity of invertebrates under Cd stress. Cd stress had no effect on the color, size and length of testis. However, Cd significantly increased the contents of catalase, glutathione peroxidase and malondialdehyde, the antioxidants in the testis of P. pseudoannulata. Then we analyzed the transcriptome of testis exposed to Cd, and identified a total of 4739 differentially expressed genes (DEGs) compared to control, with 2368 up-regulated and 2371 down-regulated. The enrichment analysis showed that Cd stress could affect spermatogenesis, sperm motility, post-embryonic development, oxidative phosphorylation and metabolism and synthesis of male reproductive components. At the same time, the protein-protein interaction network was constructed with the generated DEGs. Combined with the enrichment analysis of key modules, it revealed that Cd stress could further affect the metabolic process in testis. In general, the analysis of testicular damage and transcriptome under Cd stress can provide a novel insight into the reproductive toxicity of Cd on rice filed arthropods and offer a reference for the protection of rice filed spiders under Cd pollution.