Archives of Insect Biochemistry and Physiology最新文献

Transgenerational immune priming (TGIP) is a phenomenon in which parental exposure to pathogen infection enhances resistance to pathogens in their offspring. TGIP has been reported in several insects, including Lepidoptera, but it has not yet been documented in silkworms. In this study, we demonstrated the existence of TGIP in silkworms by exposing the parental generation to a low dose of Bombyx mori nucleopolyhedrovirus (BmNPV). Notably, when maternal or paternal-primed moths were mated to produce the F1 generation, the F1 generation larvae from both primed groups were more resistant to the BmNPV challenge than silkworm larvae with only maternal or paternal priming. Importantly, both maternal and paternal contributions to offspring immunity were essential for TGIP. However, due to the characteristics of the BmNPV itself, no within-generation immune responses were detected following BmNPV priming. Further analysis revealed that immune-related genes might play a role in mediating specific TGIP in silkworms after BmNPV priming. These results broaden our understanding of TGIP and the antiviral memory of insects in their offspring.

As a key acetyltransferase, Bombyx mori cAMP response element-binding protein (CREB)-binding protein (BmCBP) plays an important role in post-translational modifications, affecting protein stability and immune response in silkworm; however, its mechanism of action remains unclear. In this study, we designed and synthesized Nano-dsRNA nanoparticles targeting BmCBP and validated their impact on BmApoLp-III protein expression. Using an E. coli expression system, we successfully synthesized nano-dsRNA targeting BmCBP, which significantly reduced BmCBP transcription level, thereby decreasing the acetylation and protein expression levels of BmApoLp-III. The knock-down of BmCBP by nano-dsRNA also increased the ubiquitination level of BmApoLp-III, suggesting a competitive relationship between acetylation and ubiquitination. These findings show that design and synthesis of efficient nano-dsRNA nanoparticles targeting BmCBP provide a novel tool and approach for studying gene expression and regulation in silkworm and other insects.

Technologies for controlled protein targeting allow the selective manipulations of proteins resulting in their degradation and/or loss of function. Over the past two decades, these technologies have overcome the limitations of genetic methods and have become powerful tools in biological research and the search for new therapeutic approaches to disease treatment. Various methods of protein degradation and inactivation have been successfully applied to a model organism such as Drosophila melanogaster. In this article, we overview the capabilities and prospects of the Drosophila in vivo model for testing and developing modern methods of controlled protein targeting, analyzing their efficacy at the organism level and solving fundamental biological problems.

Feeding bees carbohydrates, as a substitute for nectar, has become essential in modern beekeeping. We compared the effects of 65% sucrose (SS) and 65% invert sugar (IS) syrups on the survival and enzyme activity of caged honey bees. Specifically, we analyzed glycosidase activity in the head and midgut of the bees and compared the composition of sucrose-based (SH) and invert sugar-based (IH) “honey” stored by the bees and collected from the comb. Glycosidase activity was similar in head in contrast to midgut where it was higher in IS fed bees, which appeared to be residual yeast β-fructofuranosidase activity. Fructose to glucose ratio in SH were 60.84/39.16 and a presence of some other sugars were detected, while ratio in IH were 48.49/51.51, almost exactly the same as in start fed (IS) (48.57/51.43). It has been demonstrated that glycosidase activity in IH was residual yeast β-fructofuranosidase activity. Zymogram detected α-amylase band in SH, in contrast to IH, which suggest that honey bees do not add amylase into IS. In contrast to SH, no crystallization occurred in IH. SS and IS densities were 1.23 and 1.24 g/mL, respectively, increasing to 1.35 g/mL in SH and 1.28 g/mL in IH after processing. This suggests that higher humidity and restricted cleansing flight make it harder for bees to remove excess water from IH, leading to increased midgut and hindgut weight, which correlates with higher mortality in the third week for the IS-fed group and fourth week for the SS-fed group.

Patched-related (Ptr) is a transmembrane protein implicated in developmental processes in Drosophila melanogaster, yet its precise role remains incompletely understood. Here, we use Ptr^23c null mutants to investigate the functional significance of Ptr through the entire life cycle monitoring survival during embryonic, larval, pupal and adult development, and studying larval locomotion and muscle structure. We report that Ptr^23c larvae displayed impaired hatching, indicative of defective embryonic development. Moreover, mutant larvae exhibited reduced mobility and lethargy, suggesting a potential involvement of Ptr in neuromuscular function. Morphological analysis of somatic muscles in mutant larvae revealed enlarged cell nuclei. Despite high preadult mortality, a subset of Ptr^23c mutant adults display an unexpected extension in lifespan compared to controls, implicating Ptr in the regulation of longevity. Our findings provide critical insights into the multifaceted role of Ptr in Drosophila development, highlighting its contributions to post-embryonic survival, neuromuscular function, and lifespan regulation. This study underscores the significance of exploring broader genetic networks to unravel the complexities of developmental processes.

The Oriental fruit fly, Bactrocera dorsalis (B. dorsalis) is a highly invasive, widely distributed notorious pest restricting global fruit trade immensely. There are several approaches to managing this pest, still require newer approaches. In this regard, recently a novel approach called precision-guided sterile insect technique (pgSIT) is gaining momentum in inducing both female sex elimination or sex conversion and male sterility at one go. Developing a species-specific pgSIT system requires validation of targets such as sex determination and spermatogenesis genes. In this regard, B. dorsalis is highly amenable for area-wide pest management and in the present study, we have validated the loss-of-function of the spermatogenesis-related gene, tektin1 using the CRISPR/Cas9 ribonucleoprotein (RNP) complex. This gene was cloned from the local isolate of B. dorsalis and two promising single guide RNAs (sgRNAs) were designed and validated through in vitro restriction analysis. Injection of the RNP complex (sgRNA + Cas9 protein) into the G0 embryo resulted in three adult males carrying mutations at the target site. The phenotype of the mutants was determined through crossing studies, namely, △1♂ × WT ♀, △2♂ × WT ♀, △3♂ × WT ♀, and WT ♂ × WT ♀ and that showed hatching rates of 0%, 11.70%, 0%, and 45.12%, respectively. The mutant males had more nonviable sperm as compared to control. This study underscores the pivotal role of the Bdtektin1 gene for male fertility and is a promising candidate for further development of pgSIT system for B. dorsalis.

Insecticides play a crucial role as the primary means of controlling agricultural pests, preventing significant damage to crops. However, the misuse of these insecticides has led to the development of resistance in insect pests against major classes of these chemicals. The emergence of resistance poses a serious threat, especially when alternative options for crop protection are limited for farmers. Addressing this challenge and developing new, effective, and sustainable pest management approaches is not merely essential but also critically important. In the absence of alternative solutions, understanding the root causes behind the development of resistance in insects becomes a critical necessity. Without this understanding, the formulation of effective approaches to combat resistance remains elusive. With insecticides playing a vital role in global food security and public health, understanding and mitigating resistance are paramount. Given the growing concern over insect resistance to insecticides, this review addresses a crucial research gap by thoroughly examining the causes, mechanisms, and potential solutions. The review examines factors driving resistance, such as evolutionary pressure and excessive pesticide use, and provides a detailed analysis of mechanisms, including detoxifying enzyme overproduction and target site mutations. Providing an analysis of potential solutions, it discusses integrated pest management, strategic insecticide rotation, and the use of new pest control technologies and biological agents. Emphasizing the urgency of a multifaceted approach, the review provides a concise roadmap for sustainable pest management, guiding future research and applications.