A Role of Suppressor of Cytokine Signaling 2 in the Regulation of Ecdysteroid Signaling Pathway in Procambarus clarkii

Upregulation of miR-144-3p alleviates Doxorubicin-induced heart failure and cardiomyocytes apoptosis via SOCS2/PI3K/AKT axis

MicroRNAs (miRs) are implicated in heart failure (HF). Thereby, we aim to uncover the role of miR-144-3p in HF. Doxorubicin (Dox)-induced HF model was constructed in rats and cardiomyocytes H9C2, and the cardiac function was determined using ultrasound cardiogram. Morphology of cardiac tissue was observed using hematoxylin-eosin (H&E) staining. The viability and apoptosis of Dox-treated and transfected cardiomyocytes were determined using Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Relative expressions of the HF-associated miRs (including miR-144-3p), suppressor of cytokine signaling 2 (SOCS2), apoptosis- and phosphoinositide 3-kinase (PI3K)/AKT pathway-related factors (B-cell lymphoma 2, Bcl-2; Bcl-2 associated X protein, Bax; cleaved [C] capsase-3; phosphoinositide 3-kinase, PI3K; phosphorylated-PI3K, p-PI3K; p-AKT; AKT) were measured with quantitative real-time polymerase chain reaction or Western blot. Target gene of miR-144-3p was predicted by Starbase and TargetScan and confirmed with dual-luciferase reporter assay. Dox caused rat cardiac dysfunction, aggravated cardiac injury, decreased cardiomyocytes viability, and the expression of miR-144-3p, Bcl-2, and phosphorylation of both PI3K and AKT yet the upregulated those of Bax and C caspase-3, which was reversed by upregulating miR-144-3p, whereas downregulating miR-144-3p did oppositely. SOCS2 was the target gene of miR-144-3p, Dox promoted SOCS2 expression, which was reversed by upregulating miR-144-3p, while downregulating miR-144-3p did conversely. In addition, silencing SOCS2 reversed the effects of miR-144-3p downregulation in Dox-treated cardiomyocytes. Upregulating miR-144-3p alleviated Dox-induced cardiac dysfunction and cell apoptosis via targeting SOCS2, providing a novel evidence of miR-144-3p in HF.

Involvement of gamma interferon inducible lysosomal thiol reductase in the innate immune responses of red swamp crayfish, Procambarus clarkii

The Gamma interferon inducible lysosomal thiol reductase (GILT) plays a key biological role in the immune responses and involves in the processing of class II MHC-restricted antigen by stimulating disulfide bond reduction in mammals. To determine the biological function of GILT in the innate immune system of crustaceans, we sequenced and cloned GILT gene from red swamp crayfish, Procambarus clarkii (Pc-GILT). The deduced amino acid sequence of Pc-GILT contained the putative conserved structures of the GILT family proteins: the GILT signature (CQHGX2ECX2NX4C) sequence and the active site (CXXS) motif. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis suggested that a recombinant Pc-GILT protein was successfully expressed in Escherichia coli (E. coli). Quantitative real-time PCR analysis showed that Pc-GILT transcript level was highest in the hepatopancreas followed by the gut, heart and muscles. Additionally, we analyzed the transcription level of Pc-GILT gene in hepatopancreas of red swamp crayfish under biotic stress conditions. The expression of Pc-GILT gene upregulated after viral (poly I:C) and bacterial (peptidoglycan, lipopolysaccharide) infection. The suppression of Pc-GILT by double stranded RNA influenced the transcript levels of various immune-related genes. These observations indicate that the Pc-GILT probably plays a key biological role in the innate immune responses of red swamp crayfish, since it modulates the expression of genes associated with immune pathways.

Molecular Cloning and Expression Analysis of Three Suppressors of Cytokine Signaling Genes (SOCS5, SOCS6, SOCS7) in the Mealworm Beetle Tenebrio molitor

Suppressors of cytokine signaling (SOCS) influence cytokine and growth factor signaling by negatively regulating the Janus kinase (JAK)-signal transducers and activators of transcription (STAT) pathway to maintain homeostasis during immune responses. However, functional characterization of SOCS family members in invertebrates is limited. Here, we identified and evaluated three SOCS genes (type I sub-family) in the mealworm beetle Tenebrio molitor. The full-length open reading frames (ORFs) of TmSOCS5, TmSOCS6, and TmSOCS7 comprised of 1389, 897, and 1458 nucleotides, encoding polypeptides of 462, 297, and 485 amino acids, respectively. The SH2 and SOCS box domains of the TmSOCS C-terminal region were highly conserved. Phylogenetic analysis revealed that these SOCS genes were clustered within the type I subfamily that exhibits the highest amino acid identity with Tribolium castaneum SOCS genes. Contrary to TmSOCS7 expression, the expression levels of TmSOCS5 and TmSOCS6 were lower in the larval, pupal, and adult stages. In larvae and adults, the expression levels of TmSOCS5 and TmSOCS6 were highest in the hemocytes and ovaries, respectively. SOCS transcripts were also highly upregulated in the hemocytes of T. molitor larvae within 3–6 h post-infection with the fungus Candida albicans. Collectively, these results provide valuable information regarding the involvement of TmSOCS type-I subfamily in the host immune response of insects.

A role of cathepsin L gene in innate immune response of crayfish (Procambarus clarkii)

Cathepsin L is one of the crucial enzyme superfamilies and involved in the immune responses. In the present study, cathepsin L gene from the red crayfish Procambarus clarkii, named PcCTSL, was cloned and characterized. The cDNA fragment of PcCTSL was 1026 bp in length, which encoded a putative protein of 341 amino acid residues with a molecular weight of 37.884 kDa. The theoretical isoelectric point was 5.218. The prepro-cathepsin L was comprised of a typical signal peptide (Met₁-Ala₁₈), a prodomain proregion peptide (Trp₂₉-Phe₈₉) and a mature peptide (Leu₁₂₄-Leu₃₄₀). Homology analysis indicated that PcCTSL exhibited 53.2%-87.1% identity to other selected species. The recombinant protein of PcCTSL was successfully expressed in Escherichia coli and rabbit anti-PcCTSL polyclonal antibodies were prepared. Real-time quantitative reverse transcription-PCR (qPCR) analysis revealed that the PcCTSL was expressed in all examined tissues, while the greatest mRNA level was observed in hepatopancreas. The expression of PcCTSL mRNA was clearly up regulated in hepatopancreas after challenge by lipopolysaccharide (LPS) and polyriboinosinic polyribocytidylic acid (Poly I:C). RNA interference of PcCTSL affected the gene expression of members of the Toll pathway. Our results suggest that the PcCTSL may play an important role to defend P. clarkii against the pathogens infection.

Characterization and function of a novel calmodulin-like protein from crayfish Procambarus clarkii

Calmodulin plays an important role in calcium-dependent signal transduction pathways. In this experiment, a novel calmodulin-like gene (Pc-CaM-L) was identified in the crayfish Procambarus clarkii; it encodes a polypeptide of 145 amino acids. Quantitative real-time PCR analysis revealed that Pc-CaM-L was expressed in all examined tissues, including hepatopancreas, hemocytes, heart, gill, intestine and muscle; the highest Pc-CaM-L expression level was detected in the hepatopancreas. Sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blot analysis demonstrated that a recombinant Pc-CaM-L protein was successfully expressed in Escherichia coli. The calcium-binding activity of the purified Pc-CaM-L protein was confirmed by gel mobility shift assay. The expression of Pc-CaM-L was significantly upregulated in gut, gill and hemocytes after lipopolysaccharide or polyinosinic:polycytidylic acid induction. These results suggest that Pc-CaM-L plays a role in the immune response of P. clarkii.