Life history responses of the small brown planthopper Laodelphax striatellus to temperature change

Decoding Peroxidase Gene Function in Heat Stress Adaptation of Tetranychus urticae: Unraveling Molecular Mechanisms of Short-Term Thermal Tolerance

Tetranychus urticae (Acari: Tetranychidae) is a widely distributed agricultural pest, and it possesses an exceptional capacity to withstand or adapt to short-term heat stress. To investigate the molecular mechanisms underlying this heat tolerance, using both transcriptome and whole-genome data, we identified six distinct POD genes in T. urticae and characterized their physicochemical properties and structural features. Real-time quantitative PCR (RT-qPCR) was utilized to analyze the expression profiles of these genes under short-term heat stress. Our results show that T. urticae mitigates heat-induced oxidative stress through the upregulation of POD gene expression, highlighting the critical role of these genes in the mite's adaptive response to thermal stress. These findings contribute to a deeper understanding of the molecular pathways that enable T. urticae to survive in fluctuating thermal environments, which is increasingly relevant in the context of global climate change. Furthermore, this study provides a foundation for future research utilizing RNA interference (RNAi) technology to further investigate the functional roles of these POD genes and their potential as targets for pest control strategies.

Maintenance of persistent transmission of a plant arbovirus in its insect vector mediated by the Toll-Dorsal immune pathway

Throughout evolution, arboviruses have developed various strategies to counteract the host's innate immune defenses to maintain persistent transmission. Recent studies have shown that, in addition to bacteria and fungi, the innate Toll-Dorsal immune system also plays an essential role in preventing viral infections in invertebrates. However, whether the classical Toll immune pathway is involved in maintaining the homeostatic process to ensure the persistent and propagative transmission of arboviruses in insect vectors remain unclear. In this study, we revealed that the transcription factor Dorsal is actively involved in the antiviral defense of an insect vector (Laodelphax striatellus) by regulating the target gene, zinc finger protein 708 (LsZN708), which mediates downstream immune-related effectors against infection with the plant virus (Rice stripe virus, RSV). In contrast, an antidefense strategy involving the use of the nonstructural-protein (NS4) to antagonize host antiviral defense through competitive binding to Dorsal from the MSK2 kinase was employed by RSV; this competitive binding inhibited Dorsal phosphorylation and reduced the antiviral response of the host insect. Our study revealed the molecular mechanism through which Toll-Dorsal-ZN708 mediates the maintenance of an arbovirus homeostasis in insect vectors. Specifically, ZN708 is a newly documented zinc finger protein targeted by Dorsal that mediates the downstream antiviral response. This study will contribute to our understanding of the successful transmission and spread of arboviruses in plant or invertebrate hosts.

Preliminary characterization of biomolecular processes related to plasticity in Acyrthosiphonpisum

Global warming strongly impacts many organisms' development, distribution and population structure. This problem has attracted the attention of many scientists to understand and study its actual effects, especially on insects influenced by environmental temperatures. Aphids are a model for studies of the genetics and physiology of stress. Aphids are characterized by parthenogenetic reproduction, which limits the effects of recombination on evolutionary processes, and have shown resistance to various biotic and abiotic stresses. This study was based on the hypothesis that aphids have optimized, over time, genetic mechanisms capable to give them plasticity through genome modifications mediated by transposition. To understand and evaluate the effects of heat stress, the expression levels of transposases and methylases were analyzed in mothers and daughters. Our results show that after four days from the thermal shock, methylation decreases in both mothers and daughters, while transposition significantly increases in daughters, thus generating gene variability, essential for adaptation.