Novel ApeC-containing protein mediates the recognition and internalization of Vibrio splendidus in Apostichopus japonicus.

Pattern recognition receptors (PRRs) mediate the innate immune responses and play a crucial role in host defense against pathogen infections. Apextrin C-terminal (ApeC)-containing proteins (ACPs), a newly discovered class of PRRs specific to invertebrates, recognize pathogens through their ApeC domain as intracellular or extracellular effectors. However, the other immunological functions of ACPs remain unclear.

Ferroptosis resists intracellular Vibrio splendidus AJ01 mediated by ferroportin in sea cucumber Apostichopus japonicus.

Ferroptosis, a kind of programmed cell death, is characterized with iron-dependent lipid ROS buildup, which is considered as an important cellular immunity in resisting intracellular bacterial infection in mammalian macrophages. In this process, lipid ROS oxidizes the bacterial biofilm to inhibit intracellular bacteria. However, the function of ferroptosis in invertebrate remains unknown.

Midgut microbiota affects the intestinal barrier by producing short-chain fatty acids in .

Introduction: The intestinal microbiota participates in host physiology and pathology through metabolites, in which short-chain fatty acids (SCFAs) are considered principal products and have extensive influence on intestine homeostasis. It has been reported that skin ulceration syndrome (SUS), the disease of caused by , is associated with the alteration of the intestinal microbiota composition.

Method: To investigate whether the intestinal microbiota affects health via SCFAs, in this study, we focus on the SCFA profiling and intestinal barrier function in treated with .

NEDD4 activates mitophagy by interacting with LC3 to restrain reactive oxygen species and apoptosis in Apostichopus japonicus challenged with Vibrio splendidus.

Mitophagy, the selective degradation of damaged mitochondria by autophagy, plays a crucial role in the survival of coelomocytes in Apostichopus japonicus following Vibrio splendidus infection by suppressing the generation of reactive oxygen species (ROS) and attenuating cell apoptosis. A recent study revealed that reducing the expression of the neural precursor cell-expressed developmentally downregulated gene 4 (NEDD4), an enzyme 3 (E3) ubiquitin ligase, significantly affects mitochondrial degradation. Prior to the present study, the functional role of NEDD4 in marine invertebrates was largely unexplored.

Ring Finger Protein 34 Facilitates Nervous Necrosis Virus Evasion of Antiviral Innate Immunity by Targeting TBK1 and IRF3 for Ubiquitination and Degradation in Teleost Fish.

Ubiquitination, as one of the most prevalent posttranslational modifications of proteins, enables a tight control of host immune responses. Many viruses hijack the host ubiquitin system to regulate host antiviral responses for their survival. Here, we found that the fish pathogen nervous necrosis virus (NNV) recruited Lateolabrax japonicus E3 ubiquitin ligase ring finger protein 34 (LjRNF34) to inhibit the RIG-I-like receptor (RLR)-mediated interferon (IFN) response via ubiquitinating TANK-binding kinase 1 (LjTBK1) and interferon regulatory factor 3 (LjIRF3).

Phenotypic and functional characterization of two coelomocyte subsets in Apostichopus japonicus.

The hemocytes of invertebrates are composed of different cell subsets with different morphologies and structures. Different cell subsets have different immune functions, which play an important role in innate immune response against pathogens. However, the understanding of the classification of Apostichopus japonicus coelomocytes and the molecular basis of immune function of different cell subsets is very limited.

Evolution of mitogen-activated protein kinase family and their immune function in Apostichopus japonicus.

The mitogen-activated protein kinase family plays an important role in cell differentiation, growth, proliferation, and survival. However, the current research on the mitogen-activated protein kinase (MAPK) family in invertebrates is limited to the individual gene, and the analysis has not been conducted at the family level. In the present study, echinoderm MAPK family was identified by genomic screening, and five members, including three ERK subfamily members, one c-Jun N-terminal kinase (JNK) subfamily, and one p38-MAPK member were detected.

Mesentery AjFGF4-AjFGFR2-ERK pathway modulates intestinal regeneration via targeting cell cycle in echinoderms.

Objectives: The purpose of the study aims to understand the regeneration process and its cytology mechanism in economic echinoderms.

Materials And Methods: The intestine regeneration process of Apostichopus japonicus was investigated by immunohistochemistry and the cell proliferation was detected by immunofluorescence and flow cytometry. Fibroblast growth factor 4 of A.

The Capsid Protein of Nervous Necrosis Virus Antagonizes Host Type I IFN Production by a Dual Strategy to Negatively Regulate Retinoic Acid-Inducible Gene-I-like Receptor Pathways.

Nervous necrosis virus (NNV), a highly pathogenic RNA virus, is a major pathogen in the global aquaculture industry. To efficiently infect fish, NNV must evade or subvert the host IFN for their replication; however, the precise mechanisms remain to be elucidated. In this study, we reported that capsid protein (CP) of red-spotted grouper NNV (RGNNV) suppressed the IFN antiviral response to promote RGNNV replication in brain cells, which depended on the ARM, S, and P domains of CP.

E3 Ubiquitin Ligase RNF114 Inhibits Innate Immune Response to Red-Spotted Grouper Nervous Necrosis Virus Infection in Sea Perch by Targeting MAVS and TRAF3 to Mediate Their Degradation.

RIG-I-like receptor (RLR)-mediated antiviral signaling is critical to trigger the immune response to virus infection; however, the antiviral responses are also tightly regulated to avoid uncontrolled production of type I IFN by various mechanisms, including ubiquitination. In this study, an E3 ubiquitin ligase ring finger protein 114 (RNF114) from sea perch () (LjRNF114) was identified as a suppressor of RLR signaling pathways during red-spotted grouper nervous necrosis virus (RGNNV) infection. RGNNV infection promoted the expression of LjRNF114.

Marine medaka heat shock protein 90ab1 is a receptor for red-spotted grouper nervous necrosis virus and promotes virus internalization through clathrin-mediated endocytosis.

Nervous necrosis virus (NNV) can infect many species of fish and causes serious acute or persistent infection. However, its pathogenic mechanism is still far from clear. Specific cellular surface receptors are crucial determinants of the species tropism of a virus and its pathogenesis.

Ubiquitin-specific protease 5 was involved in the interferon response to RGNNV in sea perch (Lateolabrax japonicus).

Deubiquitinases are widely involved in the regulation of the virus-triggered type I interferon (IFN) signaling. Here, we found sea perch (Lateolabrax japonicus) ubiquitin-specific protease 5 (LjUSP5) was a negative regulatory factor of the red-spotted grouper nervous necrosis virus (RGNNV)-triggered IFN response. LjUSP5 encoded a polypeptide of 830 amino acids, containing a zinc finger UBP domain (residues 197-270 aa), two ubiquitin-associated domains (residues 593-607 aa; 628-665 aa), and one UBP domain (residues 782-807 aa), and shared the closest genetic relationship with the USP5 of Larimichthys crocea.

MiR-202-5p Inhibits RIG-I-Dependent Innate Immune Responses to RGNNV Infection by Targeting TRIM25 to Mediate RIG-I Ubiquitination.

The RIG-I-like receptors (RLRs) signaling pathway is essential for inducing type I interferon (IFN) responses to viral infections. Meanwhile, it is also tightly regulated to prevent uncontrolled immune responses. Numerous studies have shown that microRNAs (miRNAs) are essential for the regulation of immune processes, however, the detailed molecular mechanism of miRNA regulating the RLRs signaling pathway remains to be elucidated.

Zebrafish TRIM25 Promotes Innate Immune Response to RGNNV Infection by Targeting 2CARD and RD Regions of RIG-I for K63-Linked Ubiquitination.

RIG-I-like receptors (RLRs) play important roles in response to virus infection by regulating host innate immune signaling pathways. Meanwhile, the RLR signaling pathway is also tightly regulated by host and virus to achieve the immune homeostasis between antiviral responses and virus survival. Here, we found that zebrafish TRIM25 (zbTRIM25) functioned as a positive regulator of RLR signaling pathway during red spotted grouper nervous necrosis virus (RGNNV) infection.

Maternal miR-202-5p is required for zebrafish primordial germ cell migration by protecting small GTPase Cdc42.

In many lower animals, germ cell formation, migration, and maintenance depend on maternally provided determinants in germ plasm. In zebrafish, these processes have been extensively studied in terms of RNA-binding proteins and other coding genes. The role of small non-coding RNAs in the regulation of primordial germ cell (PGC) development remains largely unknown and poorly investigated, even though growing interests for the importance of miRNAs involved in a wide variety of biological processes.

Isolation and identification of a viral haemorrhagic septicaemia virus (VHSV) isolate from wild largemouth bass Micropterus salmoides in China.

Fish rhabdoviruses are a family of viruses responsible for large-scale fish die-offs worldwide. Here, we reported the isolation and identification of a member of rhabdoviruses from wild largemouth bass (Micropterus salmoides) in the coastal area of the Pearl River Estuary, China. This virus isolate was identified as viral haemorrhagic septicaemia virus (VHSV) by specific RT-PCR.

Comparative transcriptome analysis reveals the role of p53 signalling pathway during red-spotted grouper nervous necrosis virus infection in Lateolabrax japonicus brain cells.

Nervous necrosis virus (NNV) is one of the fish pathogens that have caused mass mortalities of many marine and freshwater fishes in the world. To better comprehend the molecular immune mechanism of sea perch (Lateolabrax japonicus) against NNV infection, the comparative transcriptome analysis of red-spotted grouper nervous necrosis virus (RGNNV)-infected or mock-infected L. japonicus brain (LJB) cells was performed via RNA sequencing technology.

Molecular characterization of vasa homologue in marbled goby, Oxyeleotris marmorata: Transcription and localization analysis during gametogenesis and embryogenesis.

Identification of germ cell markers is important for investigating reproduction biology in fish. Vasa is one of the most studied germ cell markers in mammals and lower vertebrates including fish. Here, we characterized a vasa homologue from the fish marbled goby (Oxyeleotris marmorata), termed omvasa.

Expression pattern, antiviral role and regulation analysis of interferon-stimulated gene 15 in black seabream, Acanthopagrus schlegelii.

Interferon stimulated gene 15 (ISG15) is an IFN inducible ubiquitin-like protein and plays a critical role in immune response against viral infection. In this study, an ISG15 gene (AsISG15) was cloned and characterized from the marine fish black seabream, Acanthopagrus schlegelii. The full-length cDNA of AsISG15 was 1302 bp and encoded 155 amino acids containing two ubiquitin-like motifs and a LRGG conjugation domain.

Molecular characterization and expression analysis of interferon-gamma in black seabream Acanthopagrus schlegelii.

Interferon gamma (IFN-γ) is a major component in immunological signaling and plays a key role in resisting viral infection. In this study, we identified and characterized an IFN-γ gene (AsIFN-γ) in the marine fish black seabream (Acanthopagrus schlegelii). We cloned AsIFN-γ genomic sequence, which comprises four exons, three introns and an upstream promoter including several conserved regulatory elements.