Molecular characterization and expression of TAK-binding proteins (TAB1-3) in Larimichthys crocea infected by Vibrio parahemolyticus and LPS

Molecular characterization, expression and functional analysis of TAK1, TAB1 and TAB2 in Nile tilapia (Oreochromis niloticus)

The MAPK pathway is the common intersection of signal transduction pathways such as inflammation, differentiation and proliferation and plays an important role in the process of antiviral immunity. Streptococcus agalactiae will have a great impact on tilapia aquaculture, so it is necessary to study the immune response mechanism of tilapia to S. agalactiae. In this study, we isolated the cDNA sequences of TAK1, TAB1 and TAB2 from Nile tilapia (Oreochromis niloticus). The TAK1 gene was 3492 bp in length, contained an open reading frame (ORF) of 1809 bp and encoded a polypeptide of 602 amino acids. The cDNA sequence of the TAB1 gene was 4001 bp, and its ORF was 1491 bp, which encoded 497 amino acids. The cDNA sequence of the TAB2 gene was 4792 bp, and its ORF was 2217 bp, encoding 738 amino acids. TAK1 has an S_TKc domain and a coiled coil structure; the TAB1 protein structure contains a PP2C_SIG domain and a conserved PYVDXA/TXF sequence model; and TAB2 contains a CUE domain, a coiled coil domain and a Znf_RBZ domain. Homology analysis showed that TAK1 and TAB1 had the highest homology with Neolamprologus brichardi, and TAB2 had the highest homology with Simochromis diagramma (98.28 %). In the phylogenetic tree, TAK1, TAB1 and TAB2 formed a large branch with other scleractinian fishes. The tissue expression analysis showed that the expression of TAK1, TAB1 and TAB2 was highest in the muscle. The expression of TAK1, TAB1 and TAB2 was significantly induced in most of the tested tissues after stimulation with LPS, Poly I:C and S. agalactiae. The subcellular localization results showed that TAK1 was located in the cytoplasm, and TAB1 and TAB2 had certain distributions in the cytoplasm and nucleus. Coimmunoprecipitation (Co-IP) results showed that TRAF6 did not interact with the TAK1 protein but interacted with TAB2, while TAB1 did not interact with P38γ but interacted with TAK1. There was also an interaction between TAK1 and TAB2.

Effects of TLR2/4 signalling pathway in western mosquitofish (Gambusia affinis) after Edwardsiella tarda infection

Gambusia affinis is regarded as an important animal model. Edwardsiella tarda is one of the most serious pathogens affecting aquaculture. The study explores the effects of TLR2/4 partial signalling pathway in G. affinis of E. tarda infection. The study collected the brain, liver, and intestine after E. tarda LD₅₀ and 0.85% NaCl solution challenge at different times (0 h, 3 h, 9 h, 18 h, 24 h, and 48 h). In these three tissues, the mRNA levels of PI3K, AKT3, IRAK4, TAK1, IKKβ, and IL-1β were substantially enhanced (p < .05) then returned to normal levels. Additionally, Rac1 and MyD88 in liver had different trend with other genes in brain and intestine, which displayed significantly indifference. The overexpression of IKKβ, and IL-1β indicated that E. tarda also caused immune reaction in intestine and liver, which would be consistent with delayed edwardsiellosis, which causes intestinal lesions and liver and kidney necrosis. Additionally, MyD88 plays a smaller role than IRAK4 and TAK1 in this signalling pathways. This study could enrich the understanding of the immune mechanism of the TLR2/4 signalling pathway in fish and might help to prescribe preventive measures against E. tarda to prevent infectious diseases in fish.

Transcriptome analysis of Neocaridina denticulate sinensis challenged by Vibrio parahemolyticus

As a common aquatic pathogen, Vibrio parahaemolyticus can cause a variety of diseases of shrimp, especially acute hepatopancreatic necrosis disease (AHPND), which leads to great losses to the aquaculture industry around the world. However, the molecular mechanism of V. parahaemolyticus infection is still unclear. Neocaridina denticulate sinensis is a kind of small ornamental shrimp that is popular in aquarium trade, and due to its tenacious vitality, rapid growth, high reproductive capacity, it is very suitable to be developed as an animal model for basic research on decapod crustaceans. Thus, in this paper, transcriptomes of N. denticulate sinensis hepatopancreas with or without V. parahaemolyticus injection were explored. The results showed that a total of 23,624 genes with the N50 of 2705 bp were obtained. Comparative transcriptomic analysis revealed 21,464 differentially expressed genes between the V. parahaemolyticus infected and non-infected group, of which, 11,127 genes were up-regulated and 10,337 genes were down-regulated. Functional enrichment analysis suggested that many DEGs enriched in immune related pathways, including MAPK signaling pathway, Phosphatidylinositol signaling system, Chemokine signaling pathway, Phagosome and Jak-STAT signaling pathway and so on. Eight genes were selected randomly for qRT-PCR to verify the transcriptome sequencing results and the results showed the expression of these genes were consistent with the transcriptome results. Our work provides a unique and important dataset that contributes to the understanding of the molecular mechanisms of the immune response to V. parahaemolyticus infection and may further provide the basis for the prevention and resolution of bacterial diseases.

TAK1 of blunt snout bream promotes NF-κB activation via interaction with TAB1 in response to pathogenic bacteria

Transforming growth factor-β activated kinase-1 (TAK1) is an important upstream signaling molecules involved in the NF-κB signaling pathway. TAK1 interacts with TAB1 to form the TAK1-TAB1 complex, which elicits NF-κB activation through a series of cascade reactions in mammals. However, the function of TAK1 in blunt snout bream (Megalobrama amblycephala ( maTak1) and the effects of their interaction between TAK1 and TAB1 on the NF-κB activation still remains largely unknown. In the present study, maTak1 was cloned and characterized successfully based on transcriptome data. Its open reading frame is composed of 1626 nucleotides and the predicted maTAK1 protein contains 541 amino acids, which includes an N-terminal Serine/Threonine protein kinases (S/TKc) and a C-terminal coiled-coil region. Phylogenetic analysis showed that maTAK1 were clustered with those of other teleosts. MaTak1 displayed ubiquitous transcriptional expression in all the examined tissues of healthy blunt snout bream but with varied expression levels. And maTrak1 expression was dramatically enhanced in different tissues and MAF cells after LPS stimulation and A. hydrophila challenge. The result from subcellular localization analysis indicated that both maTAK1 and maTAB1 were cytoplasmic protein. The activity of NF-κB promoter could not be induced by overexpression of maTak1 or maTab1 alone, however, it could be enhanced by co-expression of maTak1 and maTab1. Co-immunoprecipitation and subcellular co-localization assay revealed that maTAK1 can combine with maTAB1 directly. The transcriptional expression level of pro-inflammatory cytokines (IL-1β, IL-6 and IL-8) increased distinctly after the overexpression of maTak1 and maTab1. Taken together, the data obtained in this study demonstrated that the direct interaction between maTAK1 and maTAB1 might play a pivotal role in mediating host innate immune response to pathogen invasion by the production of pro-inflammatory cytokines via NF-κB signaling pathway, which might lay a solid foundation for the establishment of novel therapeutic approach to combat bacterial infection in fish.

TAB1 regulates glycolysis and activation of macrophages in diabetic nephropathy

Objective and design

Macrophages exhibit strong phenotypic plasticity and can mediate renal inflammation by polarizing into an M1 phenotype. They play a pivotal role in diabetic nephropathy (DN). Here, we have investigated the regulatory role of transforming growth factor β-activated kinase 1-binding protein 1 (TAB1) in glycolysis and activation of macrophages during DN.

Methods

TAB1 was inhibited using siRNA in high glucose (HG)-stimulated bone marrow-derived macrophages (BMMs) and lentiviral vector-mediated TAB1 knockdown was used in streptozotocin (STZ)-induced diabetic mice. Western blotting, flow cytometry, qRT-PCR, ELISA, PAS staining and immunohistochemical staining were used for assessment of TAB1/nuclear factor-κB (NF-κB)/hypoxia-inducible factor-1α (HIF-1α), iNOS, glycolysis, inflammation and the clinical and pathological manifestations of diabetic nephropathy.

Results

We found that TAB1/NF-κB/HIF-1α, iNOS and glycolysis were up-regulated in BMMs under HG conditions, leading to release of further inflammatory factors, Downregulation of TAB1 could inhibit glycolysis/polarization of macrophages and inflammation in vivo and in vitro. Furthermore, albuminuria, the tubulointerstitial damage index and glomerular mesangial expansion index of STZ-induced diabetic nephropathy mice were decreased by TAB1 knockdown.

Conclusions

Our results suggest that the TAB1/NF-κB/HIF-1α signaling pathway regulates glycolysis and activation of macrophages in DN.

Electronic supplementary material

The online version of this article (10.1007/s00011-020-01411-4) contains supplementary material, which is available to authorized users.

Immune-related genes expression analysis of Western mosquitofish (Gambusia affinis) challenged with Aeromonas hydrophila

The great Gambusia affinis (G. affinis) is considered as an important animal model to study the endocrine disruption, ecological behavior, and environmental pollutant. The present study aims to build a new promising infection model with Aeromonas hydrophila (A. hydrophila) in aquaculture. The mRNA expression of Rac1, MyD88, IRAK4, TAK1, IKKβ, and IL-1β in G. affinis were significance higher (P < 0.05) in the liver of G. affinis than that of brain and intestine. And the PI3K mRNA expression level was significant lower (P < 0.05) in the intestine than that of brain and liver. The mRNA levels of AKT3 were significant higher (P < 0.05) in the brain than that of liver and intestine. And then the brain, liver, and intestine were collected at different time points (0 h, 3 h, 9 h, 18 h, 24 h, 48 h) after post injection of LD₅₀ of A. hydrophila. The 0.85% NaCl was used as a negative control for the LD₅₀ of A. hydrophila. The RT-PCR results showed that mRNA expressions of TLR2/4 pathway downstream genes MyD88, IRAK4, TAK1, Rac1, IKKβ, and IL-1β were firstly significantly up-regulated (P < 0.05) and were then backed to the 0 h group levels in three tissues. In contrast, mRNA expressions of TLR2/4 pathway downstream genes PI3K and AKT3 were firstly significantly decreased (P < 0.05) and were then increased to the 0 h group levels in brain and intestine. In summary, the results indicated that A. hydrophila could cause inflammatory reaction in intestinal and brain. In addition, the liver showed a provocative reaction when infected with A. hydrophila.

STAT3 Targets ERR-α to Promote Epithelial-Mesenchymal Transition, Migration, and Invasion in Triple-Negative Breast Cancer Cells

STAT3 is constitutively activated in many malignant tumor types and plays an important role in multiple aspects of cancer aggressiveness. In this study, we found that estrogen-related receptor α (ERR-α) correlating with STAT3 was highly expressed in triple-negative breast cancer (TNBC) cell lines and tissues, which was associated with both the pathologic stage and prognosis of patients with TNBC. In vitro studies showed that ERR-α promoted TNBC cell migration and invasion, which was regulated by STAT3. Phosphorylated STAT3 (p-STAT3, Tyr 705) could bind to the promotor of ERR-α, and activate its transcription, which was suggested by luciferase assay and chromatin immunoprecipitation assay. We also found that ERR-α was the key target gene regulated by STAT3 in promoting epithelial-mesenchymal transition (EMT), migration, and invasion. ERR-α upregulated the expression of ZEB1, N-cadherin, and vimentin while downregulated the expression of E-cadherin. Furthermore, in vivo studies showed that ERR-α could increase the metastasis ability of TNBC. Our finding demonstrated that ERR-α was a direct regulatory gene target of p-STAT3, which was enriched for processes involving invasion and metastasis in TNBC and provided insight into TNBC pathogenesis, as well as a potential therapeutic option against TNBC metastasis. IMPLICATIONS: Our research first showed that p-STAT3 (Tyr 705) could bind to the promotor region of ERR-α and promote EMT in TNBC by ZEB1 pathways, thus providing a potential clinical target for TNBC.