Drosophila spermatogenesis involves the renewal of germline stem cells, meiosis of spermatocytes, and morphological transformation of spermatids into mature sperm. We previously demonstrated that Ocnus (ocn) plays an essential role in spermatogenesis. The ValRS-m (Valyl-tRNA synthetase, mitochondrial) gene was down-regulated in ocn RNAi testes. Here, we found that ValRS-m-knockdown induced complete sterility in male flies. The depletion of ValRS-m blocked mitochondrial behavior and ATP synthesis, thus inhibiting the transition from spermatogonia to spermatocytes, and eventually, inducing the accumulation of spermatogonia during spermatogenesis. To understand the intrinsic reason for this, we further conducted transcriptome-sequencing analysis for control and ValRS-m-knockdown testes. The differentially expressed genes (DEGs) between these two groups were selected with a fold change of ≥2 or ≤1/2. Compared with the control group, 4725 genes were down-regulated (dDEGs) and 2985 genes were up-regulated (uDEGs) in the ValRS-m RNAi group. The dDEGs were mainly concentrated in the glycolytic pathway and pyruvate metabolic pathway, and the uDEGs were primarily related to ribosomal biogenesis. A total of 28 DEGs associated with mitochondria and 6 meiosis-related genes were verified to be suppressed when ValRS-m was deficient. Overall, these results suggest that ValRS-m plays a wide and vital role in mitochondrial behavior and spermatogonia differentiation in Drosophila.

Nicotine (NE), a principal alkaloid in tobacco, functions as both a neurotoxin and a candidate for therapeutic applications. This research explores the tri

The Chinese rice-field eel rhabdovirus (CrERV) is an emerging pathogen that causes hemorrhagic disease in Chinese rice-field eels (Monopterus albus), leadi

The Drosophila spermatogenesis has the renewal of germline stem cells, meiosis of spermatocytes, and morphological transformation of spermatids into mature sperm. We previously demonstrated that Ocnus (ocn) plays an essential role in spermatogenesis. ValRS-m (Valyl-tRNA synthetase, mito-chondrial) gene was downregulated in ocn RNAi testes. By hatchability testing, we found that ValRS-m-knockdown induced complete sterility of male flies. We also concluded that ValRS-m-knockdown inhibited the transition from spermatogonia to spermatocytes and caused accumulated spermatogonia in testes. To understand the intrinsic reason for this destruction, we further conducted transcriptome sequencing analysis in ValRS-m RNAi testes. A total of 7710 dif-ferentially expressed genes (DEGs) were identified to have at least a 2-fold change with a p-value of

Class II major histocompatibility complexes (MHC-II) are a highly polymorphic and multigenic family of molecules that present exogenous peptides to CD4 ⁺ helper T cells, thereby activating the host adaptive immune system. In this study, we systematically analyzed the genomic distribution and tissue-specific expression of MHC-II genes in Carassius gibelio . The Cagi -DDA/DFA molecule was found to be highly expressed in the spleen and head kidney, moderately expressed in the intestine, gills, and trunk kidney, and expressed at low levels in the liver and brain. A polyclonal antibody was generated against the most prevalent Cagi -DDA/DFA allele in the population. Using immunopeptidomics, we identified viral peptides bound to Cagi -DDA/DFA molecules in the head kidney tissues of C. gibelio following Cyprinid herpesvirus 2 (CyHV-2) infection. A total of 276 antigen peptides were identified, originating from 39 viral proteins. Notably, viral proteins with high abundance and early expression profiles, such as ORF88, ORF121, and ORF141 proteins, were more likely to generate antigen peptides. The identified CyHV-2 peptide epitopes presented by C. gibelio MHC-II molecules provide candidate antigens required for anti-CyHV-2 vaccine development. IMPORTANCE: Vaccination represents a cornerstone in the prevention of infectious diseases, achieving substantial success in disease control. Upon immunization, protein-derived peptides are processed and presented by major histocompatibility complex class II (MHC-II) molecules, activating CD4 ⁺ T cells and triggering adaptive immune responses. Cyprinid herpesvirus 2 (CyHV-2), a pathogenic virus in crucian carp, poses a serious threat to global aquaculture. However, the absence of a comprehensive antigenic profile for CyHV-2 has hindered the development of effective vaccines. Here, we employed immunoaffinity purification coupled with mass spectrometry to systematically identify CyHV-2-derived peptides presented by MHC-II in Carassius gibelio . We identified 276 antigenic peptides originating from 39 viral proteins, which collectively delineate the antigenic landscape of CyHV-2 and provide a rational basis for the design of a vaccine against CyHV-2.

White spot syndrome virus (WSSV) is a highly virulent pathogen associated with mass mortality in crustaceans, for which no reliable measures are currently available to control WSSV infection. Traditional Chinese medicinal herbs, such as Scutellaria baicalensis (SB), Flos Sophorae Immaturus (FSI), and Prunella vulgaris (PV), have demonstrated potential antiviral characteristics. In this research, crayfish ( Procambarus clarkii ) were adopted as a model animal to investigate the anti-WSSV efficacy of a compound herbal formulation composed of these three herbs. Moreover, the effects of WSSV infection and the compound treatment on the intestinal microbiota composition and metabolic profile of crayfish were investigated. Quantitative PCR (qPCR) analysis revealed that the herbal compound formulation reduced the viral load in the hepatopancreas, intestine, and gills of WSSV-infected crayfish. Histopathological examinations showed that WSSV infection caused severe inflammation and tissue damage in these organs, which were significantly alleviated by herbal treatment. RT-qPCR analysis further revealed that the compound upregulated the expression of innate immunity-associated genes in affected tissues. 16S rRNA sequencing revealed that WSSV infection led to severe gut dysbiosis, characterized by a significant increase in Proteobacteria . This dysbiosis was substantially improved following treatment with the compound. Moreover, untargeted metabolomics analysis revealed distinct alterations in gut metabolites resulting from both WSSV infection and herbal intervention. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis identified 20 differentially expressed metabolic pathways between the challenge (CHG) and treatment (TRE) groups. Beneficial pathways, including glycerophospholipid metabolism, pyrimidine metabolism, and CoA biosynthesis, were significantly upregulated in the TRE group. These findings collectively demonstrate that SB-FSI-PV compound effectively mitigates WSSV infection by reducing viral load, modulating immune responses, restoring gut microbial balance, and improving host metabolic function. Overall, this formulation represents a promising therapeutic approach for controlling and preventing WSSV outbreaks in aquaculture systems.