Chinese Giant Salamander Iridovirus 025L Is a Viral Essential Gene.

Ranavirus is a large nucleocytoplasmic DNA virus. Chinese giant salamander iridovirus (CGSIV) belongs to the ranavirus genus, and its replication involves a series of essential viral genes. Viral PCNA is a gene closely associated with viral replication. CGSIV-025L also encodes PCNA-like genes. We have described the function of CGSIV-025L in virus replication. The promoter of CGSIV-025L is activated during viral infection, and it is an early (E) gene that can be effectively transcribed after viral infection. CGSIV-025L overexpression promoted viral replication and viral DNA replication. siRNA interfered with CGSIV-025L expression and attenuated viral replication and viral DNA replication. The Δ025L-CGSIV strain with the deletion of CGSIV-025L could not replicate normally and could be rescued by the replenishment of 025L. CGSIV-025L was proven to be an essential gene for CGSIV by overexpression, interference, and deletion mutation experiments. CGSIV-025L was found to interact with CGSIV-062L by yeast two-hybrid, CoIP, and GST pulldown. Thus, the current study demonstrated that CGSIV-025L is an essential gene of CGSIV, which may be involved in viral infection by participating in viral DNA replication and interacting with replication-related proteins.

Hepatitis B Virus DNA Polymerase Displays an Anti-Apoptotic Effect by Interacting with Elongation Factor-1 Alpha-2 in Hepatoma Cells.

Hepatitis B virus (HBV) genome P-encoded protein HBV DNA polymerase (Pol) has long been known as a reverse transcriptase during HBV replication. In this study, we investigated the impact of HBV Pol on host cellular processes, mainly apoptosis, and the underlying mechanisms. We showed a marked reduction in apoptotic rates in the HBV Pol-expressed HepG2 cells compared to controls. Moreover, a series of assays, i.e., yeast two-hybrid, GST pull-down, co-immunoprecipitation, and confocal laser scanning microscopy, identified the host factor eEF1A2 to be associated with HBV Pol. Furthermore, knockdown of eEF1A2 gene by siRNA abrogated the HBV Pol-mediated anti-apoptotic effect with apoptosis induced by endoplasmatic reticulum (ER) stress-inducer thapsigargin (TG), thus suggesting that the host factor eEF1A2 is essential for HBV Pol's anti-apoptosis properties. Our findings have revealed a novel role for HBV Pol in its modulation of apoptosis through integrating with eEF1A2.

MiR-194 promotes hepatocellular carcinoma through negative regulation of CADM1.

Aberrant expression of microRNAs may contribute to the initiation and progression of various types of human cancer and they may also constitute biomarkers for cancer diagnosis and treatment. However, the specific function of miR-194 in hepatocellular carcinoma (HCC), and the potential mechanism of its involvement in HCC were unclear. In the present study, we found that miR-194 inhibited CADM1 protein level expression by inhibiting mRNA translation of CADM1; the expression of CADM1 was low in liver cancer cells and tumor tissues, and the high expression of miR-194 was closely related to HCC. MiR-194 promoted proliferation, invasion, migration, and cell cycle progression of HCC cells, and such promotion effect was inhibited by CADM1. In addition, miR-194 may play a tumor-promoting action in a HCC xenograft tumor model. These results suggested that miR-194 may promote the occurrence and development of HCC by inhibiting CADM1. Therefore, miR-194 may be a promising novel therapy for diagnosis of hepatocellular carcinoma.

Research on promoting liver fibrosis injury by the targeted regulation of miR-202 for HGF to activate HSC.

BACKGROUND: Liver fibrosis is the primary cause of liver cirrhosis and hepatocellular carcinoma and leads to considerable morbidity and mortality. Recent studies have shown that microRNAs are associated with fibrotic processes in liver disorders, but the exact role of miR-202 is still unclear, and its related mechanisms are not fully understood. AIMS: The aim of this research is to analyze the regarded regulation of miR-202 on HGF and its role in the pathological progress of liver fibrosis. METHODS: In the present study, qRT-PCR was used to detect the expression level of miR-202 in serum of patients with liver fibrosis and to compare its expression in patients with different pathological stages. HGF was predicted to be the target gene of miR-202 by TargetScan and was verified by Dual-luciferase reporter gene assay. qRT-PCR and western blot were used to detect the regulatory effect of mir-202 on the mRNA and protein of HGF; effect of miR-202 on the expression of fibrosis factors α-smooth muscle actin (α-SMA), FSP1, and collagen was detected; effect of miR-202 on liver fibrosis in mice was detected by establishing CCL4-induced mouse model. RESULTS: We found that the expression level of miR-202 in serum of patients with liver fibrosis was significantly higher than that of healthy people, and increased with the increase of fibrosis; miR-202 inhibited the expression level of mRNA and protein of HGF by combining with the 3'-UTR of HGF; the expression level of miR-202 significantly increased after hepatic stellate cells (HSC) were stimulated by AngII; the overexpression of miR-202 could up-regulate the expression of fibrotic factors α-SMA, FSP1, and collagen I. In addition, miR-202 up-regulated the expression of collagen I and collagen III in liver tissue of mice with liver fibrosis and promoted the progress of liver fibrosis. CONCLUSIONS: miR-202 could negatively regulate the expression of target gene HGF, activated HSC, and increased the expression levels of various fibrosis factors, and the pathological process of liver fibrosis injury was promoted.

Design and evaluation of novel thrombin-based GLP-1 analogs with peptidic albumin binding domain for the controlled release of GLP-1.

Currently, the curative effects of polypeptide drugs are often restricted due to the short in vivo duration of action. In this study, we fused a series of heptapeptide tags with different length fatty chains to the N-terminus of mutated glucagon-like peptide-1 (GLP-1) using an intermediate sequence comprising a flexible linker (GGGGS)2 and thrombin (TBN)-cleavable site (FNPR), to develop promising prolonged GLP-1 receptor (GLP-1R) agonists. As a result, twenty-one fusion peptides, termed PES01-PES21, were designed and prepared. Surface plasmon resonance (SPR) measurements and plasma stability tests showed that PES14 exert better albumin binding affinity and in vitro plasma stability compared with the other ones. Preclinical assay in db/db mice proved that PES14 exert the hypoglycemic efficacies in a dose-dependent model within the range of 10-90 nmol kg-1. Furtherly, an enhanced glucose-lowering effect and significantly prolonged hypoglycemic duration of PES14 were exhibited in multiple oral glucose tolerance tests (OGTTs) and hypoglycemic duration test, compared with Liraglutide and Semaglutide, respectively. Moreover, the in vivo t 1/2 of intact PES14 and released GLP-1 were approximately 95.1 h and 110.5 h in rhesus monkeys after a single subcutaneous injection of 90 nmol kg-1, respectively. Furthermore, long-term treatment with PES14 in db/db mice for 8 weeks obtained beneficial efficacies on body weight gain, food intake, fat% and hemoglobin A1c (HbA1c) reduction compared with the control and superior to those of Semaglutide treatment. Meanwhile, chronic treatment of PES14 also exhibited proper insulin immunoreactivity and effectively enhanced the improvement on hepatocyte damage. All these results suggested that PES14 has the potential to be developed as a once-weekly anti-diabetic drug.