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Silk gland size in silkworms (Bombyx mori) affects silk output. However, the molecular mechanisms by which genes regulate silk gland size remain unclear. In this study, silk glands from three pure silkworm strains (A798, A306 and XH) with different silk gland weight phenotypes were compared using transcriptomics and proteomics to identify differentially expressed genes (DEGs) and proteins (DEPs). When comparing A798 to A306 and A798 to XH, 830 and 469 DEGs were up‐regulated, respectively. These genes were related to the gene ontology terms, metabolic process, transport activity and biosynthesis process. In addition, 372 and 302 up‐regulated differentially expressed proteins were detected in A798 to A306 and A798 to XH, respectively, related to the gene ontology terms, ribosome and protein export, ribosome and polypeptide biosynthesis processes. Moreover, combined transcriptomics, proteomics and weighted correlation network analyses showed that five genes (BGIBMGA002524, BGIBMGA002629, BGIBMGA005659, BGIBMGA005711 and BGIBMGA010889) were significantly associated with the silk gland weight. Reverse Transcription‐quantitative real‐time Polymerase Chain Reaction (RT‐qPCR) and Enzyme linked immunosorbent assay (ELISA) were used to verify the mRNA and protein expression of five genes in the silk glands and tissues of 18 silkworm strains. The results showed that four genes have higher expression levels in heavier silk glands. These genes are associated with glycogen metabolism, fatty acid synthesis and branched chain amino acid metabolism, thus potentially promoting growth and silk protein synthesis. These findings provide valuable insights into the molecular mechanisms underlying the relationship between silk gland weight and silk yield in silkworms. [ABSTRACT FROM AUTHOR]

Cyber‐aggression is a serious social problem worldwide. Its risks have been frequently explored, and violence exposure in daily life has been regarded as an important risk factor of cyber‐aggression. However, the longitudinal association between violence exposure in daily life and cyber‐aggression has not yet been examined, and the mechanisms underlying the link between violence exposure and cyber‐aggression remain largely unclear. Based on the General Aggression Model and Script Theory, we explored the circular relation between violence exposure in daily life, hostile automatic thoughts, and cyber‐aggression. The current study adopted a longitudinal design to address these issues among 941 college students. The results indicated violence exposure in daily life predicted hostile automatic thoughts and cyber‐aggression 6 months later; hostile automatic thoughts predicted violence exposure and cyber‐aggression 6 months later; and cyber‐aggression predicted hostile automatic thoughts and violence exposure 6 months later. Moreover, each of them plays a mediating role in the association between the other two variables. These results support and expand the General Aggression Model and Script Theory that violence exposure, aggressive cognition, and aggression facilitate each other. This also provides theoretical guidance on reducing cyber‐aggression in daily life. [ABSTRACT FROM AUTHOR]

Snakehead vesiculovirus (SHVV), a strain of negative-stranded RNA viruses extracted from sick snakehead fish (Ophicephalus striatus), may pose a threat to the health of snakehead fish. Previous research has proved that the replication of SHVV can be significantly inhibited by glutamine starvation. To study how glutamine starvation inhibits SHVV replication, channel catfish ovary (CCO) cells with SHVV cultivated in the glutamine-free medium or the complete medium were used to investigate the differentially expressed proteins (DEPs). The results showed that 124 up-regulated and 246 down-regulated proteins were involved in many viral replication physiological processes, such as autophagy, post-translational modifications machinery, and functional pathways, including the PI3K-Akt signaling pathway and mTOR signaling pathway. Furthermore, a few proteins, such as Akt and Hsp90, which have been confirmed to be involved in the replication of RNA viruses, were also significantly differentially expressed. Taken together, our study demonstrated that glutamine starvation affects various functional pathways and the expression of some key proteins related to RNA viral replication, which will benefit future studies on the replication mechanisms of SHVV and the prevention of SHVV infection. [ABSTRACT FROM AUTHOR]

Snakehead vesiculovirus (SHVV) causes enormous economic losses in snakehead fish (Ophicephalus striatus) culture. Understanding replication mechanisms of virus is considerable significance in preventing and treating viral disease. In our previous studies, we have reported that glutamine starvation could significant inhibit the replication of SHVV. Furthermore, we also showed that SHVV infection could cause apoptosis of striped snakehead fish cells (SSN-1). However, the underlying mechanisms remain enigmatic. To decipher the relationships among the viral infection, glutamine starvation and apoptosis, SSN-1 cells transcriptomic profilings of SSN-1 cells infected with or without SHVV under glutamine deprived condition were analyzed. RNA-seq was used to identify differentially expressed genes (DEGs). Our data revealed that 1215 up-regulated and 226 down-regulated genes at 24 h post-infection were involved in MAPK, apoptosis, RIG-1-like and toll-like receptors pathways and glutamine metabolism. Subsequently, DEGs of glutamine metabolism and apoptosis pathways were selected to validate the sequencing data by quantitative real-time PCR (qRT-PCR). The expression patterns of both transcriptomic data and qRT-PCR were consistent. We observed that lack of glutamine alone could cause mild cellular apoptosis. However, lack of glutamine together with SHVV infection could synergistically enhance cellular apoptosis. When the cells were cultured in complete medium with glutamine, overexpression of glutaminase (GLS), an essential enzyme for glutamine metabolism, could significantly enhance the SHVV replication. While, SHVV replication was decreased in cells when GLS was knocked down by specific siRNA, indicating that glutamine metabolism was essential for viral replication. Furthermore, the expression level of caspase-3 and Bax was significantly decreased in SHVV infected cells with GLS overexpression. By contrast, they were significantly increased in SHVV infected cells with GLS silence by SiRNA, indicating that SHVV infection activated the Bax and caspase-3 pathways to induce apoptosis independent of glutamine. Our results reveal that SHVV replication and starvation of glutamine could synergistically promote the cellular apoptosis, which will pave a new way for developing strategies against the vial infection. • Transcriptomic data of cells infected by SHVV with glutamine deprivation was analyzed. • Lack of glutamine and SHVV infection enhanced cellular apoptosis synergistically. • SHVV infection activated the Bax and caspase-3 pathways independent of glutamine. [ABSTRACT FROM AUTHOR]

Abstract Autophagy is a degradation cellular process which also plays an important role in virus infection. Glutamine is an essential substrate for the synthesis of glutathione which is the most abundant thiol-containing compound within the cells and plays a key role in the antioxidant defense and intracellular signaling. There is an endogenous cellular glutathione pool which consists of two forms of glutathione, i.e. the reduced form (GSH) and the oxidized form (GSSG). GSH serves as an intracellular antioxidant to maintain cellular redox homeostasis by scavenging free radicals and other reactive oxygen species (ROS) which can lead to autophagy. Under physiological conditions, the concentration of GSSG is only about 1% of total glutathione, while stress condition can result in a transient increase of GSSG. In our previous report, we showed that the replication of snakehead fish vesiculovirus (SHVV) was significant inhibited in SSN-1 cells cultured in the glutamine-starvation medium, however the underlying mechanism remains enigmatic. Here, we revealed that the addition of L-Buthionine-sulfoximine (BSO), a specific inhibitor of the GSH synthesis, could decrease the γ- glutamate-cysteine ligase (GCL) activity and GSH levels, resulting in autophagy and significantly inhibition of the replication of SHVV in SSN-1 cells cultured in the complete medium. On the other hand, the replication of SHVV was rescued and the autophagy was inhibited in the SSN-1 cells cultured in the glutamine-starvation medium supplemented with additional GSH. Furthermore, the inhibition of the synthesis of GSH had not significantly affected the generation of reactive oxygen species (ROS). However, it significantly decreased level of GSH and enhanced the level of GSSG, resulting in the decrease of the value of GSH/GSSG, indicating that it promoted the cellular oxidative stress. Overall, the present study demonstrated that glutamine starvation impaired the replication of SHVV in SSN-1 cells via inducing autophagy associated with the disturbance of the endogenous glutathione pool. Highlights • Glutamine starvation induced autophagy in SSN-1 cells. • Inhibition of the synthesis of glutathione induced autophagy, resulting in the inhibiting of SHVV replication. • Glutamine starvation induced autophagy by disturbing endogenous glutathione pool as well as GSH/GSSG ratio. [ABSTRACT FROM AUTHOR]

The giant freshwater prawn (Macrobrachium rosenbergii) is a commercially valuable freshwater crustacean species that frequently appears a death affected by various diseases, resulting in substantial economic losses. Improving the survival rate of M. rosenbergii is a hot and essential issue for feeding the prawns. Scutellaria polysaccharide (SPS) extracted from Scutellaria baicalensis (a Chinese medicinal herb) is conducive to the survival rate of organisms by enhancing immunity and antioxidant ability. In this study, M. rosenbergii was fed 50, 100, and 150 mg/kg of SPS. The immunity and antioxidant capacity of M. rosenbergii were tested by mRNA levels and enzyme activities of related genes. The mRNA expressions of NF-κB, Toll-R, and proPO (participating in the immune response) in the heart, muscle, and hepatopancreas were decreased after four weeks of SPS feeding (P < 0.05). This indicated that long-term feeding of SPS could regulate the immune responses of M. rosenbergii tissues. The activity levels of antioxidant biomarkers, alkaline phosphatase (AKP), and acid phosphatase (ACP) had significant increases in hemocytes (P < 0.05). Moreover, catalase (CAT) activities in the muscle and hepatopancreas, as well as superoxide dismutase (SOD) activities in all tissues, significantly decreased after four weeks of culture (P < 0.05). The results demonstrated that long-term feeding of SPS could improve the antioxidant capacity of M. rosenbergii. In summary, SPS was conducive to regulating the immune capacity and enhancing the antioxidant capacity of M. rosenbergii. These results provide a theoretical basis for supporting SPS addition to the feed of M. rosenbergii. • The immunity and antioxidant capacity of M. rosenbergii were tested. • Scutellaria polysaccharide feeding did not improve the weight of M. rosenbergii. • Scutellaria polysaccharide improved the antioxidant capacity of Mrosenbergii. [ABSTRACT FROM AUTHOR]

Bacterial contamination has caused a major public health problem worldwide. Bacillus cereus is a conditional environmental pathogenic bacteria that can cause food poisoning. Whether environmental pathogens can cause widespread transmission in the insect kingdom is unclear. In this study, a Bacillus cereus ZJ-4 was isolated from the hospital environment of Zhenjiang City, Jiangsu Province, China. It was fatal by injection into the silkworm hemolymph. To investigated the potential toxic factors of ZJ-4 and clarified the toxicity response mechanism of silkworm by the ZJ-4 infection. Then, the whole genome of ZJ-4 was sequenced, and the immune mechanism of silkworm fat body to ZJ-4 pathogen was studied by HE pathological section and proteomics. Bacterial genome sequencing indicated that ZJ-4 had 352 drug resistance genes and 6 virulence genes. After 36 h of subcutaneous puncture with ZJ-4 suspension, the pathological changes were obviously found in HE pathological sections of fat body tissue. Comparative proteomic results indicated that differentially expressed proteins are mainly involved in stress reactions, biological regulation, and innate immunity. The qRT-PCR analysis showed that the expressions of β-GRP , Spaetzle , MyD88 , Tube and Dorsal genes in Toll pathway were up-regulated, while Pell and Cactus genes were down-regulated; in the antimicrobial peptide pathway, Glv2 , Lzm , Mor, and Leb3 genes were up-regulated, while attacin1 and defensin genes were down-regulated; Sod gene was up-regulated, while Cat gene was down-regulated in the antioxidant pathway; Ldh , Sdh , and Mdh genes were down-regulated in glucose metabolism pathway. These results indicated that ZJ-4 can damage the innate immune pathway of silkworm, and also affect the normal immune function of fat body cells. [Display omitted] • A new B. cereus strain named Bacillus cereus ZJ-4 was isolated from hospital environmental. • The whole genome information of B. cereus ZJ-4 was sequenced. • The virulence genes of B. cereus ZJ-4 were difference from other Bacillus cereus. • B. cereus ZJ-4 could damage the innate immune response of silkworm fat body. [ABSTRACT FROM AUTHOR]

Resveratrol, a natural polyterpenoid, can scavenge reactive oxygen species in vivo to carry out the functions of antioxidation and antiaging. Resveratrol's anti-cancer capability has attracted widespread attention, but its molecular mechanism has not been systematically explained. In this study, by comparing the activity of normal cell lines and cancer cell lines after treating with resveratrol, it was found that resveratrol has more significant cytotoxicity in cancer cell lines. Resveratrol could play a toxic role through inducing apoptosis of the cancer cell in a time- and concentration-dependent manner. A total of 330 significantly differential genes were identified through large-scale transcriptome sequencing, among which 103 genes were upregulated and 227 genes were downregulated. Transcriptome and qRT-PCR data proved that a large number of genes related to cell cycle were differentially expressed after the treatment of resveratrol. The changes of cell cycle phases at different time points after treating with resveratrol were further detected, and it was found that the cells were arrested in the S phase because of the percentage of cells in S phase increased and cells in G1/G0 phase decreased. In conclusion, resveratrol can inhibit the proliferation of 4T1 cancer cells by inhibiting cell cycle and inducing apoptosis. [ABSTRACT FROM AUTHOR]

Snakehead vesiculovirus (SHVV) is a negative-sense single-stranded RNA virus that infects snakehead fish. This virus leads to illness and mortality, causing significant economic losses in the snakehead aquaculture industry. The replication and spread of SHVV in cells, which requires glutamine as a nitrogen source, is accompanied by alterations in intracellular metabolites. However, the metabolic mechanisms underlying the inhibition of viral replication by glutamine deficiency are poorly understood. This study utilized liquid chromatography-mass spectrometry to measure the differential metabolites between the channel catfish Parasilurus asotus ovary cell line infected with SHVV under glutamine-containing and glutamine-deprived conditions. Results showed that the absence of glutamine regulated 4 distinct metabolic pathways and influenced 9 differential metabolites. The differential metabolites PS(16:0/16:0), 5,10-methylene-THF, and PS(18:0/18:1(9Z)) were involved in amino acid metabolism. In the nuclear metabolism functional pathway, differential metabolites of guanosine were observed. In the carbohydrate metabolism pathway, differential metabolites of UDP-d-galacturonate were detected. In the signal transduction pathway, differential metabolites of SM(d18:1/20:0), SM(d18:1/22:1(13Z)), SM(d18:1/24:1(15 Z)), and sphinganine were found. Among them, PS(18:0/18:1(9Z)), PS(16:0/16:0), and UDP-d-galacturonate were involved in the synthesis of phosphatidylserine and glycoprotein. The compound 5,10-methylene-THF provided raw materials for virus replication, and guanosine and sphingosine are related to virus virulence. The differential metabolites may collectively participate in the replication, packaging, and proliferation of SHVV under glutamine deficiency. This study provides new insights and potential metabolic targets for combating SHVV infection in aquaculture through metabolomics approaches.

Snakehead fish vesiculovirus (SHVV), a member of the family Rhabdoviridae, has caused mass mortality in snakehead fish culture in China. Previous transcriptomic sequencing of SHVV-infected and non-infected striped snakehead fish cells (SSN-1) showed that glutaminase (GLS), the critical enzyme of glutamine metabolism, was upregulated upon SHVV infection. It therefore drew our attention to investigating the role of glutamine in SHVV propagation. Glutamine deprivation significantly reduced the expression of the mRNAs and proteins of SHVV, and the production of virus particles, indicating that glutamine was required for SHVV propagation. Glutamine can be converted to glutamate by GLS, and then be converted to α-ketoglutarate, to join in the tricarboxylic acid (TCA) cycle. Addition of the TCA cycle intermediate α-ketoglutarate, oxaloacetic acid or pyruvate significantly restored SHVV propagation, indicating that the requirement of glutamine for SHVV propagation was due to its replenishment of the TCA cycle. Inhibiting the activity of GLS in SSN-1 cells by an inhibitor, bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl)ethyl sulfide, decreased SHVV propagation, while overexpression of GLS increased SHVV propagation. Taken together, our data have revealed the relationship between glutamine metabolism and SHVV propagation.