Cultivation of earthworms and analysis of associated bacterial communities during earthworms' growth using two types of agricultural wastes.

Earthworm cultivation can effectively promote the resource utilization of agricultural waste. The efficient utilization of agricultural waste by earthworms mainly depends on the microbial communities in the guts. This study used silkworm excrement and cow manure as substrates for earthworm cultivation and investigated the associated bacterial communities during earthworms' growth. The survival rate of earthworms remained above 89% after 21 days of feeding with the two substrates. Proteobacteria, Actinobacteria, and Firmicutes constituted the predominant bacterial communities in earthworm growth, accounting for over 81% of the relative abundance in both guts and vermicompost. The bacteria richness and diversity in the foregut and midgut of earthworm were lower than those in the hindgut. The prediction function of intestinal bacterial communities of earthworms cultured with two substrates mainly involved biosynthesis, decomposition and energy production.

Ad libitum feeding of silkworm larvae powder-containing diets specifically influences metabolism-related and short-chain fatty acid-producing gut bacteria in mice.

Silkworm (Bombyx mori) larvae are expected to be useful as an ingredient in entomophagy. They are full of nutrients, including indigestible proteins; however, there have been few studies on the effects of the consumption of the entire body of silkworms on the intestinal microflora. We prepared a customized diet containing silkworm larval powder (SLP), and investigated the effects of ad libitum feeding of the SLP diet on the intestinal microbiota and the amount of short-chain fatty acids (SCFAs) in mice. We found that the diversity of the cecal and fecal microbiota increased in the mice fed the SLP diet (SLP group), and that the composition of their intestinal microbiota differed from that of the control mice. Furthermore, a genus-level microbiota analysis showed that in the SLP group, the proportions of Alistipes, Lachnospiraceae A2, and RF39, which are associated with the prevention of obesity, were significantly increased, while the proportions of Helicobacter and Anaerotruncus, which are associated with obesity, were significantly decreased. Additionally, the level of butyrate was increased in the SLP group, and Clostridia UCG 014 and Lachnospiraceae FCS020 were found to be associated with the level of butyrate, one of the major SCFAs. These findings indicated that silkworm powder may be useful as an insect food that might also improve obesity.

Effects of poly (ADP-ribose) polymerase 1 (PARP1) on silk proteins in the silkworm, Bombyx mori.

Animal silk is economically important, while silk secretion is a complex and subtle mechanism regulated by many genes. We identified the poly (ADP-ribose) polymerase (PARP1) gene of the silkworm and successfully cloned its coding sequence (CDS) sequence. Using clustered regularly interspaced short palindromic repeat (CRISPR/Cas9) technology, we screened single guide RNA (sgRNA) with high knockout efficiency by cellular experiments and obtained PARP1 mutants by knocking out the PARP1 gene of the silkworm at the individual level. We found that the mutants mainly exhibited phenotypes such as smaller cocoon size and reduced cocoon shell rate than the wild type. We also detected the expression of silk protein genes in the mutant by quantitative real-time PCR (qPCR) and found that the expression of some silk protein genes was slightly down-regulated. Meanwhile, together with the results of transcriptomic analysis, we hypothesized that PARP1 may affect the synthesis of silk proteins, resulting in their failure to function properly. Our study may provide an important reference for future in-depth refinement of the molecular mechanism of silk protein expression in silk-producing animals, as well as a potential idea for future development of molecular breeding lines of silkworms to improve silk production.

Alteration of ß-glucan in the emerging fungal pathogen Candida auris leads to immune evasion and increased virulence.

Candida auris is an emerging pathogenic yeast that has been categorized as a global public health threat and a critical priority among fungal pathogens. Despite this, the immune response against C. auris infection is still not well understood. Hosts fight Candida infections through the immune system that recognizes pathogen-associated molecular patterns such as ß-glucan, mannan, and chitin on the fungal cell wall. In this study, levels of ß-glucan and mannan exposures in C. auris grown under different physiologically relevant stimuli were quantified by flow cytometry-based analysis. Lactate, hypoxia, and sublethal concentration of fluconazole trigger a decrease in surface ß-glucan while low pH triggers an increase in ß-glucan. There is no inverse pattern between exposure levels of ß-glucan and mannan in the cell wall architecture among the three clades. To determine the effect of cell wall remodeling on the immune response, a phagocytosis assay was performed, followed by quantification of released cytokines by ELISA. Lactate-induced decrease in ß-glucan leads to reduced uptake of C. auris by PMA-differentiated THP-1 and RAW 264.7 macrophages. Furthermore, reduced production of CCL3/MIP-1⍺ but not TNF-⍺ and IL-10 were observed. An in vivo infection analysis using silkworms reveals that a reduction in ß-glucan triggers an increase in the virulence of C. auris. This study demonstrates that ß-glucan alteration occurs in C. auris and serves as an escape mechanism from immune cells leading to increased virulence.

Characterization of the UDP-glycosyltransferase UGT33D1 in silkworm Bombyx mori.

Uridine diphosphate (UDP)-glycosyltransferases (UGTs) are important metabolizing enzymes functioning by adding a sugar moiety to a small lipophilic substrate molecule and play critical roles in drug/toxin metabolism for all realms of life. In this study, the silkworm Bombyx mori UGT33D1 gene was characterized in detail. UGT33D1 was found localized in the endoplasmic reticulum (ER) compartment just like other animal UGTs and was mainly expressed in the silkworm midgut. We first reported that UGT33D1 was important to BmNPV infection, as silencing UGT33D1 inhibited the BmNPV infection in silkworm BmN cells, while overexpressing the gene promoted viral infection. The molecular pathways regulated by UGT33D1 were analysed via transcriptome sequencing upon UGT33D1 knockdown, highlighting the important role of the gene in maintaining a balanced oxidoreductive state of the organism. In addition, proteins that physically interact with UGT33D1 were identified through immunoprecipitation and mass spectrometry analysis, which includes tubulin, elongation factor, certain ribosomal proteins, histone proteins and zinc finger proteins that had been previously reported for human UGT-interacting proteins. This study provided preliminary but important functional information on UGT33D1 and is hoped to trigger deeper investigations into silkworm UGTs and their functional mechanisms.

Expression of dengue capsid-like particles in silkworm and display of envelope domain III of dengue virus serotype 2.

Dengue virus (DENV) is a considerable public health threat affecting millions of people globally. Vaccines for dengue are an important strategy to reduce the disease burden. We expressed capsid (C2) and envelope domain III of dengue virus serotype 2 (2EDIII) separately in the silkworm expression system. We conjugated them employing the monomeric streptavidin (mSA2) and biotin affinity to display the antigenic 2EDIII on the C2-forming capsid-like particle (CLP). Purified 2EDIII-displaying C2 (CLP/2EDIII) was immunogenic in BALB/c mice, eliciting neutralizing antibodies confirmed by a single-round infectious particle (SRIP) neutralization assay. Th1 cytokine levels were upregulated for the CLP/2EDIII group, and the anti-inflammatory IL-10 and pro-inflammatory IL-6 cytokine levels were also raised compared to the 2EDIII and the control groups. Elevated cytokine levels for CLP/2EDIII indicate the importance of displaying the 2EDIII as CLP/2EDIII rather than as an individual subunit. This study is the first to express the C2 protein as self-assembling CLP in vivo and 2EDIII separately in the silkworm expression system and conjugate them to form a monovalent CLP. Thus, this CLP/2EDIII display method may pave the way for an efficient tetravalent dengue vaccine candidate.

Induction of acute silkworm hemolymph melanization by Staphylococcus aureus treated with peptidoglycan-degrading enzymes.

Staphylococcus aureus, a Gram-positive bacterium, causes inflammatory skin diseases, such as atopic dermatitis, and serious systemic diseases, such as sepsis. In the skin and nasal environment, peptidoglycan (PGN)-degrading enzymes, including lysozyme and lysostaphin, affects S. aureus PGN. However, the effects of PGN-degrading enzymes on the acute innate immune-inducing activity of S. aureus have not yet been investigated. In this study, we demonstrated that PGN-degrading enzymes induce acute silkworm hemolymph melanization by S. aureus. Insoluble fractions of S. aureus treated with lysozyme, lysostaphin, or both enzymes, were prepared. Melanization of the silkworm hemolymph caused by the injection of these insoluble fractions was higher than that of S. aureus without enzyme treatment. These results suggest that structural changes in S. aureus PGN caused by PGN-degrading enzymes affect the acute innate immune response in silkworms.

Perilipin1 inhibits Nosema bombycis proliferation by promoting Domeless- and Hop-mediated JAK-STAT pathway activation in Bombyx mori.

Lipid droplets (LDs) are dynamic organelles that participate in the regulation of lipid metabolism and cellular homeostasis inside of cells. LD-associated proteins, also known as perilipins (PLINs), are a family of proteins found on the surface of LDs that regulate lipid metabolism, immunity, and other functions. In silkworms, pébrine disease caused by infection by the microsporidian Nosema bombycis (Nb) is a severe threat to the sericultural industry. Although we found that Nb relies on lipids from silkworms to facilitate its proliferation, the relationship between PLINs and Nb proliferation remains unknown. Here, we found Nb infection caused the accumulation of LDs in the fat bodies of silkworm larvae. The characterized perilipin1 gene (plin1) promotes the accumulation of intracellular LDs and is involved in Nb proliferation. plin1 is similar to perilipin1 in humans and is conserved in all insects. The expression of plin1 was mostly enriched in the fat body rather than in other tissues. Knockdown of plin1 enhanced Nb proliferation, whereas overexpression of plin1 inhibited its proliferation. Furthermore, we confirmed that plin1 increased the expression of the Domeless and Hop in the JAK-STAT immune pathway and inhibited Nb proliferation. Taken together, our current findings demonstrate that plin1 inhibits Nb proliferation by promoting the JAK-STAT pathway through increased expression of Domeless and Hop. This study provides new insights into the complicated connections among microsporidia pathogens, LD surface proteins, and insect immunity.IMPORTANCELipid droplets (LDs) are lipid storage sites in cells and are present in almost all animals. Many studies have found that LDs may play a role in host resistance to pathogens and are closely related to innate immunity. The present study found that a surface protein of insect lipid droplets could not only regulate the morphological changes of lipid droplets but also inhibit the proliferation of a microsporidian pathogen Nosema bombycis (Nb) by activating the JAK-STAT signaling pathway. This is the first discovery of the relationship between microsporidian pathogen and insect lipid surface protein perilipin and insect immunity.

The combined effects of ultrasound and plasma-activated water on silkworm pupae:Physicochemical properties, microbiological diversity and ultrastructure.

A novel technique was proposed for processing silkworm pupae by combining plasma- activated water (PAW) with ultrasound (US). The microbial diversity and quality characteristics of the silkworm pupae were also evaluated. The results of the microbial diversity analysis indicated that PAW combined with US treatment significantly reduced the relative abundance of Streptococcaceae, Leuconostocaceae, and Acetobacteraceae from 32%, 18% and 16% to 27%, 11% and 11%, respectively. Microstructural analysis demonstrated that the collapse of the internal structure of chitin in silkworm pupae facilitated the release of nutrients and flavour compounds including fatty acids, water-soluble proteins (WSP), amino acids, phenolics, and volatile compounds. Furthermore, the increase in antioxidant capacity and the decrease in catalase activity and malondialdehyde content confirmed the mechanism of quality change. These findings provide new insights into the possible mechanism of PAW combined with US to improve the quality of edible insects.

Dietary inclusion of defatted silkworm (Bombyx mori L.) pupa meal in broiler chickens: phase feeding effects on nutritional and sensory meat quality.

The present experiment was conducted to test the effect of a 4% defatted silkworm (Bombyx mori) pupae meal (SWM) incorporation into chickens' diets at different growth phases on meat quality characteristics and sensory traits. Ninety ROSS 308 day-old male broiler chickens were randomly assigned to 3 dietary groups, with 5 replicated pens/diet: the first group received a control (C) diet throughout the growing period of 42 d, the second group received a diet with 4% SWM (SWM1) during the starter phase (1-10 d) and the C diet up to slaughter, whereas the third group was fed the C diet during the starter phase and 4% SWM during the grower and finisher phases (SWM2). Diets were isonitrogenous and isoenergy, and birds had free access to feed and water throughout the experimental trial. At 42 d of age, 15 chickens/treatment were slaughtered at a commercial abattoir. Fatty acid (FA) and amino acid (AA) profiles and contents of meat, as well as its oxidative status, were determined in both breast and leg meat cuts. Also, a descriptive sensory analysis was performed on breast meat by trained panelists. Results highlighted that the SWM2 treatment increased the n-3 proportion and content in both breast and leg meat, thereby improving the omega-6/omega-3 (n-6/n-3) ratio in both cuts (P < 0.001). However, the dietary treatment had no significant effect on the oxidative status of either breast or leg meat (P > 0.05). The SWM had a limited impact on overall sensory traits of breast meat, but it contributed to improve meat tenderness in SWM-fed chickens (P < 0.01). Furthermore, SWM1 meat exhibited higher juiciness (P < 0.05) and off flavor intensity (P < 0.05) compared to the control meat. Overall, the present experiment indicated that defatted SWM holds promise as an alternative ingredient in chicken rations, ensuring satisfactory meat quality. Furthermore, administering SWM during the grower-finisher phase demonstrated beneficial effects on meat healthiness, ultimately enhancing n-3 fatty acids content and reducing the n-6/n-3 ratio.

Assessing the quality and eco-beneficial microbes in the use of silkworm excrement compost.

Sericulture has become widespread globally, and the utilization of artificial diets produces a substantial quantity of silkworm excrement. Although silkworm excrement can be composted for environmentally friendly disposal, the potential utility of the resulting compost remains underexplored. The aim of this study was to assess the quality of this unique compost and screen for eco-beneficial microbes, providing a new perspective on microbial research in waste management, especially in sustainable agriculture. The low-concentration compost application exhibited a greater plant growth-promoting effect, which was attributed to an appropriate nutritional value (N, P, K, and dissolved organic matter) and the presence of plant growth-promoting bacteria (PGPB) within the compost. Encouraged by the "One Health" concept, the eco-benefits of potent PGPB, namely, Klebsiella pneumoniae and Bacillus licheniformis, in sericulture were further evaluated. For plants, K. pneumoniae and B. licheniformis increased plant weight by 152.44 % and 130.91 %, respectively. We also found that even a simple synthetic community composed of the two bacteria performed better than any single bacterium. For animals, K. pneumoniae significantly increased the silkworm (Qiufeng × Baiyu strain) cocoon shell weight by 111.94 %, which could increase sericulture profitability. We also elucidated the mechanism by which K. pneumoniae assisted silkworms in degrading tannic acid, a common plant-derived antifeedant, thereby increasing silkworm feed efficiency. Overall, these findings provide the first data revealing multiple beneficial interactions among silkworm excrement-derived microbes, plants, and animals, highlighting the importance of focusing on microbes in sustainable agriculture.

Biochemical characterization of Bombyx mori Dicer-2 that dices double-stranded RNAs into 20-nt small RNA.

We detected enzymatic activity that generates 20-nucleotide (nt) RNA from double-stranded RNAs (dsRNAs) in crude extracts prepared from various silkworm (Bombyx mori) organs. The result using knocked-down cultured cells indicated that this dicing activity originated from B. mori Dicer-2 (BmDcr2). Biochemical analyses revealed that BmDcr2 preferentially cleaves 5'-phosphorylated dsRNAs at the 20-nt site-counted from the 5'-phosphorylated end-and required ATP and magnesium ions for the dicing reaction. This is the first report of the biochemical characterization of Dicer-2 in lepidopteran insects. This enzymatic property of BmDcr2 in vitro is consistent with the in vivo small interfering RNA profile in virus-infected silkworm cells.

MicroRNA bmo-miR-31-5p inhibits apoptosis and promotes BmNPV proliferation by targeting the CYP9e2 gene of Bombyx mori.

BACKGROUND: Bombyx mori nuclear polyhedrosis virus (BmNPV), as a typical baculovirus, is the primary pathogen that infects the silkworm B. mori, a lepidopteran species. Owing to the high biological safety of BmNPV in infecting insects, it is commonly utilized as a biological insecticide for pest control. Apoptosis is important in the interaction between the host and pathogenic microorganisms. MicroRNAs (miRNAs) influence immune responses and promote stability of the immune system via apoptosis. Therefore, the study of apoptosis-related miRNA in silkworms during virus infection can not only provide support for standardizing the prevention and control of diseases and insect pests, but also reduce the economic losses to sericulture caused by the misuse of biological pesticides. RESULTS: Through transcriptome sequencing, we identified a miRNA, miR-31-5p, and demonstrated that it can inhibit apoptosis in silkworm cells and promote the proliferation of BmNPV in BmE-SWU1 cells. We identified a target gene of miR-31-5p, B. mori cytochrome P450 9e2 (BmCYP9e2), and demonstrated that it can promote apoptosis in silkworm cells and inhibit the proliferation of BmNPV. Moreover, we constructed transgenic silkworm strains with miR-31-5p knockout and confirmed that they can inhibit the proliferation of BmNPV. CONCLUSION: These data indicate that miR-31-5p may exert functions of inhibiting apoptosis and promoting virus proliferation by regulating BmCYP9e2. The findings demonstrate how miRNAs influence host cell apoptosis and how they are involved in the host immune system response to viruses, providing important insights into the applications of biological insecticides for pest control. © 2024 Society of Chemical Industry.

Gut Microbiota Analysis in Silkworms (Bombyx mori) Provides Insights into Identifying Key Bacterials for Inclusion in Artificial Diet Formulations.

The gut microbiome significantly influences the health and productivity of silkworms (Bombyx mori), the cornerstone of sericulture. With the increasing use of cost-effective artificial diets in sericulture, it is crucial to understand how these diets impact the silkworm gut microbiomes. Here we employed 16S rRNA sequencing to delineate the impact of three distinct dietary regimens on the silkworm gut microbiomes: exclusive mulberry leaf diet (SY), exclusive artificial feed diet (SL), and a sequential transition from artificial feed to mulberry leaves (ZS). Our results unveiled stark differences in microbial diversity across the groups, with the ZS group displaying an intermediary complexity. LefSe and random forest analyses identified Methylobacteriaceae, Microbacterium, and Rhodococcus as significantly enriched in the ZS group, suggesting their potential to facilitate silkworms' adaptation to dietary transitions. Functional profiling revealed differential pathway regulation, indicating a metabolic reconfiguration in response to dietary modulations. Notably, the enrichment of Lactobacillus and Weissella in both the SL and ZS groups highlights their potential as probiotics in artificial diets. Our findings provide insights into the diet adaptation mechanisms of silkworm gut microbiota, paving the way for harnessing the intestinal bacteria to enhance silkworm health and silk production through targeted microbial interventions in sericulture practices.

Role of small nucleolar RNAs in alternative splicing of the doublesex gene in the silkworm, Bombyx mori.

More and more evidence shows that small noncoding RNAs (ncRNAs) play diverse roles in development, stress response and other cellular processes, but functional study of intermediate-size ncRNAs is still rare. Here, the expression profile of 16 intermediate-size ncRNAs in ovary and testis of silkworm Bombyx mori were analyzed. Twelve ncRNAs, including 5 small nucleolar RNAs (snoRNAs) and 7 unclassified ncRNAs, accumulated more in the testis than in the ovary of silkworm, especially Bm-163, Bm-51 and Bm-68. Four ncRNAs (including three orphan snoRNAs and one unclassified ncRNA) had higher expression level in the ovary than in the testis, especially Bm-86. Overexpression of the testis-enriched snoRNA Bm-68 in the female led to the accumulation of male-specific isoform of doublesex (BmdsxM) and increased the expression ratio of BmdsxM: BmdsxF. While overexpression of ovary-enriched snoRNA Bm-86 in the male decreased the expression ratio of BmdsxM: BmdsxF, indicating the roles of the two snoRNAs played in the alternative splicing of Bmdsx of silkworm, which will provide new clues for the functional study of snoRNAs in insects.

Rotenone-induced PINK1/Parkin-mediated mitophagy: establishing a silkworm model for Parkinson's disease potential.

Parkinson's disease (PD), ranking as the second most prevalent neurodegenerative disorder globally, presents a pressing need for innovative animal models to deepen our understanding of its pathophysiology and explore potential therapeutic interventions. The development of such animal models plays a pivotal role in unraveling the complexities of PD and investigating promising treatment avenues. In this study, we employed transcriptome sequencing on BmN cells treated with 1 µg/ml rotenone, aiming to elucidate the underlying toxicological mechanisms. The investigation brought to light a significant reduction in mitochondrial membrane potential induced by rotenone, subsequently triggering mitophagy. Notably, the PTEN induced putative kinase 1 (PINK1)/Parkin pathway emerged as a key player in the cascade leading to rotenone-induced mitophagy. Furthermore, our exploration extended to silkworms exposed to 50 µg/ml rotenone, revealing distinctive motor dysfunction as well as inhibition of Tyrosine hydroxylase (TH) gene expression. These observed effects not only contribute valuable insights into the impact and intricate mechanisms of rotenone exposure on mitophagy but also provide robust scientific evidence supporting the utilization of rotenone in establishing a PD model in the silkworm. This comprehensive investigation not only enriches our understanding of the toxicological pathways triggered by rotenone but also highlights the potential of silkworms as a valuable model organism for PD research.

Contrasting gut bacteriomes unveiled between wild Antheraea assamensis Helfer (Lepidoptera: Saturniidae) and domesticated Bombyx mori L. (Lepidoptera: Bombycidae) silkworms.

BACKGROUND: Insect gut microbiomes play a fundamental role in various aspects of insect physiology, including digestion, nutrient metabolism, detoxification, immunity, growth and development. The wild Muga silkworm, Antheraea assamensis Helfer holds significant economic importance, as it produces golden silk. METHODS AND RESULTS: In the current investigation, we deciphered its intricate gut bacteriome through high-throughput 16S rRNA amplicon sequencing. Further, to understand bacterial community dynamics among silkworms raised under outdoor environmental conditions, we compared its gut bacteriomes with those of the domesticated mulberry silkworm, Bombyx mori L. Most abundant bacterial phyla identified in the gut of A. assamensis were Proteobacteria (78.1%), Bacteroidetes (8.0%) and Firmicutes (6.6%), whereas the most-abundant phyla in B. mori were Firmicutes (49-86%) and Actinobacteria (10-36%). Further, Gammaproteobacteria (57.1%), Alphaproteobacteria (10.47%) and Betaproteobacteria (8.28%) were the dominant bacterial classes found in the gut of A. assamensis. The predominant bacterial families in A. assamensis gut were Enterobacteriaceae (27.7%), Comamonadaceae (9.13%), Pseudomonadaceae (9.08%) Flavobacteriaceae (7.59%) Moraxellaceae (7.38%) Alteromonadaceae (6.8%) and Enterococcaceae (4.46%). In B. mori, the most-abundant bacterial families were Peptostreptococcaceae, Enterococcaceae, Lactobacillaceae and Bifidobacteriaceae, though all showed great variability among the samples. The core gut bacteriome of A. assamensis consisted of Pseudomonas, Acinetobacter, Variovorax, Myroides, Alteromonas, Enterobacter, Enterococcus, Sphingomonas, Brevundimonas, Oleispira, Comamonas, Oleibacter Vagococcus, Aminobacter, Marinobacter, Cupriavidus, Aeromonas, and Bacillus. Comparative gut bacteriome analysis revealed a more complex gut bacterial diversity in wild A. assamensis silkworms than in domesticated B. mori silkworms, which contained a relatively simple gut bacteriome as estimated by OTU richness. Predictive functional profiling of the gut bacteriome suggested that gut bacteria in A. assamensis were associated with a wide range of physiological, nutritional, and metabolic functions, including biodegradation of xenobiotics, lipid, amino acid, carbohydrate metabolism, and biosynthesis of secondary metabolites and amino acids. CONCLUSIONS: These results showed great differences in the composition and diversity of gut bacteria between the two silkworm species. Both insect species harbored core bacterial taxa commonly found in insects, but the relative abundance and composition of these taxa varied markedly.

Physiological and transcriptomic responses of silkworms to graphene oxide exposure.

The growing use of nanomaterials has sparked significant interest in assessing the insect toxicities of nanoparticles. The silkworm, as an economically important insect, serves as a promising model for studying how insects respond to harmful substances. Here, we conducted a comprehensive investigation on the impact of graphene oxide (GO) on silkworms using a combination of physiological and transcriptome analyses. GO can enter the midguts and posterior silk glands of silkworms. High GO concentrations (> 25 mg/L) significantly (P < 0.01) inhibited larval growth. Additionally, GO (> 5 mg/L) significantly reduced the cocooning rate, and GO (> 15 mg/L) hindered oviduct development and egg laying in silkworms. GO increased the reactive oxygen species content and regulated catalase activity, suggesting that it may affect insect growth by regulating reactive oxygen detoxification. The transcriptome data analysis showed that 35 metabolism-related genes and 20 ribosome biogenesis-related genes were differentially expressed in response to GO, and their expression levels were highly correlated. Finally, we propose that a Ribosome biogenesis-Metabolic signaling network is involved in responses to GO. The research provides a new perspective on the molecular responses of insects to GO.

An In-Depth Insight into the Profile, Mechanisms, Functions, and Transfer of Essential Amino Acids from Mulberry Leaves to Silkworm Bombyx mori L. Pupae and Fish.

The silkworm Bombyx mori, the second most varied group of insects, is a fascinating insect that belongs to the Lepidoptera species. We aimed to deepen our knowledge about the composition and significance of amino acids (AA) from the sericulture chain to fish. AAs are the most prevalent molecules throughout the growth process of silkworms. We described AAs classification, occurrence, metabolism, and functions. Online datasets revealed that the essential AAs (EAA) level in fish meal and silkworm pupae (SWP) is comparable. SWP have a high content of methionine and lysine, which are the principal limiting AAs in fish diets, indicating that SWP have nutritional potential to be added to fish diets. Additionally, an overview of the data analyzed displays that SWP have a higher protein efficiency ratio than fish meal, the classical protein-rich source (>1.19 times), and compared to soybean meal, the second-most preferred source of protein in aquaculture (>2.08 times), indicating that SWP can be considered effective for animal feeding. In this study, we provide an overview of the current knowledge concerning AAs, paying special emphasis to EAAs and explaining, to some extent, certain mechanisms and functions of these compounds, from mulberry leaves to larvae-pupae and fish diets.

A Simple and Low-Cost CRISPR/Cas9 Knockout System Widely Applicable to Insects.

The CRISPR/Cas9 gene-editing system is a standard technique in functional genomics, with widespread applications. However, the establishment of a CRISPR/Cas9 system is challenging. Previous studies have presented numerous methodologies for establishing a CRISPR/Cas9 system, yet detailed descriptions are limited. Additionally, the difficulties in obtaining the necessary plasmids have hindered the replication of CRISPR/Cas9 techniques in other laboratories. In this study, we share a detailed and simple CRISPR/Cas9 knockout system with optimized steps. The results of gene knockout experiments in vitro and in vivo show that this system successfully knocked out the target gene. By sharing detailed information on plasmid sequences, reagent codes, and methods, this study can assist researchers in establishing gene knockout systems.