Protein 4.1R regulates M1 macrophages polarization via glycolysis, alleviating sepsis-induced liver injury in mice.

Acute liver injury (ALI) is a common clinical disease caused by sepsis, metabolic syndrome, hepatitis virus. Macrophage plays an important role in the development of ALI, which is characterized by polarization and inflammatory regulation. The polarization process of macrophages is related to membrane binding proteins and adaptors. Protein 4.1R acts as an adaptor, linking membrane proteins to the cytoskeleton, and is involved in cell activation and cytokine secretion. However, whether protein 4.1R is involved in regulating macrophage polarization and inflammation-induced liver injury remains unknown. In this study, protein 4.1R is identified with the special effect on macrophage M1 polarization. And it is further demonstrated that protein 4.1R deficiency significantly enhance glycolytic metabolism. Mechanistically, the regulation of protein 4.1R on pyruvate kinase M2 (PKM2) plays a key role in glycolysis metabolism. In addition, we found that protein 4.1R directly interacts with toll-like receptor 4 (TLR4), inhibits the activation of the AKT/HIF-1α signaling pathway. In conclusion, protein 4.1R targets HIF-1α mediated glycolysis regulates M1 macrophage polarization, indicating that protein 4.1R is a candidate for regulating macrophage mediated inflammatory response. In conclusion, we have revealed a novel function of protein 4.1R in macrophage polarization and ALI, providing important insights into the metabolic reprogramming, which is important for ALI therapy. We have revealed a novel function of protein 4.1R in macrophage polarization and ALI, providing important insights into the metabolic reprogramming, which is important for ALI therapy.

Cell membrane skeletal protein 4.1R participates in entry of Zika virus into cells.

Zika virus (ZIKV) is a typical mosquito-borne flavivirus known to cause severe fetal microcephaly and adult Guillain-Barré syndrome. Currently, there are no specific drugs or licensed vaccines available for ZIKV infection, and further research is required to identify host cell proteins involved in the virus's life cycle. Viruses are known to use host cell membrane skeletal proteins, such as actin and spectrin, to complete cell entry, transportation, and release. Here, based on immunoprecipitation, the Axl and ZIKV envelope (E) protein were shown to interact with the cell membrane skeleton protein 4.1R. Furthermore, deletion of 4.1R significantly reduced virus titer and viral protein synthesis. Our study showed that 4.1R is an important host cell protein during ZIKV infection and may be involved in the process of viral entry into host cells.

Systemic Expression Analysis Reveals Prognostic Significance of WIPI3 in Hepatocellular Carcinoma.

INTRODUCTION: WD repeat domain phosphoinositide-interacting protein 3 (WIPI3) is a member of the WIPI protein family, autophagy marker, that is associated with the malignant progression of various human cancers, but its role in hepatocellular carcinoma (HCC) is still unclear. MATERIALS AND METHODS: Firstly, we collected the mRNA expression of WIPI3 in HCC through the platform of Oncomine, as well as the DNA copy number variations (CNVs), and verified it on human HCC cell line and the GEO database. Then, the subgroups and prognosis of HCC were performed by the UALCAN web tool. The mutation of WIPI3 was analyzed by cBioPortal. The coexpression of WIPI3 in HCC was identified from the LinkedOmics database, and function enrichment analysis was done using the LinkFinder module in LinkedOmics. Coexpression gene network was constructed through the STRING database, and the MCODE plug-in of which was used to build the gene modules; both of them were visualized by the Cytoscape software. Finally, the top modular genes in the same patient cohort were constructed through data mining in The Cancer Genome Atlas (TCGA) liver hepatocellular carcinoma (LIHC) by using the UCSC Xena browser. RESULTS: The results indicated that WIPI3 was frequently overexpressed in HCC, which could lead to a poor prognosis through the Kaplan-Meier (KM) analysis. Moreover, there existed mutations of WIPI3 in HCC, and the prognosis of WIPI3-altered group was significantly poor based on KM plotter data. Coexpression analysis showed that the coexpression gene of WIPI3 was associated with cell cycle and spliceosome. Further analysis suggested that WIPI3 and eukaryotic translation initiation factor 4A3 (EIF4A3) coordinately regulated the cancer cell cycle by spliceosome as a result of the strong positive correlation between them. CONCLUSION: In summary, WIPI3 is constantly overexpressed in HCC tissues, resulting in a poor prognosis; therefore, we can identify it as an effective target for the treatment of HCC.

[Construction of a stable 4.1R gene knockout cell model in RAW264.7 cells using CRISPR/Cas9 technique].

OBJECTIVE: To construct a cell model of 4.1R gene knockout in murine macrophage cell line RAW264.7 using CRISPR/Cas9 technique. METHODS: Three high?grade small?guide RNAs (sgRNAs) that could specifically identify 4.1R gene were synthesized and inserted into lentiCRISPRv2 plasmid. RAW264.7 cells were infected with sgRNA?Cas9 lentivirus from 293T cells transfected with the recombinant sgRNA?lentiCRISPRv2 plasmid, and the positive cells were screened using puromycin and the monoclonal cells were obtained. The expression of 4.1R protein in the monoclonal cells was measured by Western blotting, and the mutation site was confirmed by sequence analysis. Result A 4.1R gene knockout RAW264.7 cell line was obtained, which showed a 19?bp deletion mutation in the 4.1R gene sequence and obviously enhanced proliferation. CONCLUSION: We successfully constructed a 4.1R gene knockout macrophage cell line using CRISPR/Cas9 technique, which may facilitate further investigation of the function of 4.1R in macrophages.

[Expression of protein 4.1 family in melanoma cell lines and its effect on cell proliferation].

OBJECTIVE: To detect the expression of protein 4.1 family members in mouse melanoma cell lines and evaluate their effect on cell proliferation. METHODS: PCR and Western blot were used to detected to the expression of protein 4.1 family members (4.1R, 4.1B, 4.1G, and 4.1N) at the mRNA and protein levels in B16 and B16-F10 cell lines. The expression plasmid vector pEGFP-N1-EPB41L3 carrying 4.1B gene sequence amplified from genomic RNA of mouse embryo fibroblasts was constructed and transiently transfected into mouse melanoma cells. The change in cell proliferation was assessed using MTT assay. RESULTS: The mRNA and protein expressions of all the protein 4.1 family members, with the exception of 4.1B, were detected in both B16 and B16-F10 cells. Transfection of cells with the eukaryotic expression vector pEGFP-N1-EPB41L3 markedly inhibited cell proliferation as compared with the non-transfected cells. CONCLUSION: The eukaryotic expression vector carrying EPB41L3 sequence is capable of inhibiting the proliferation of mouse melanoma B16 and B16-F10 cells.

Fusion expression of Helicobacter pylori neutrophil-activating protein in E.coli.

AIM: To produce a recombinant protein rMBP-NAP, which was fusionally expressed by Helicobacter pylori (H pylori) neutrophil-activating protein (NAP) and E. coli maltose-binding protein (MBP) and to evaluate its immunoreactivity and immunogenicity. METHODS: Neutrophil-activating protein gene of H pylori (HP-napA) was subcloned from the recombinant plasmid pNEB-napA, and fused to MalE gene of expressing vector pMAL-c2x. The recombinant plasmid pMAL-c2x-napA was confirmed by restriction enzyme digestion, and then transformed into E. coli TB1. Fusion protein rMBP-NAP was induced by IPTG and identified by SDS-PAGE analysis. Soluble rMBP-NAP was purified by amylose affinity chromatography. Immunoreactivity and immunogenicity of the fusion protein were evaluated by animal experiment, Western blotting with human H pylori anti-sera. RESULTS: E.coli TB1 carrying recombinant plasmid pMAL-c2x-napA was constructed and led to a high efficiency cytosol expression of fusion protein rBMP -NAP when induced by IPTG. The molecular weight of rBMP-NAP was about 57 kD, accounting for 37.55% of the total protein in the sonicated supernatant of E. coli TB1 (pMAL-c2x-napA). The purity of the fusion protein after one-step affinity chromatography was 94% and the yield was 100 mg per liter of bacterial culture. The purified fusion protein could be specifically recognized by both human anti-sera from clinical patients with H pylori infection and rabbit sera immunized by rMBP-NAP itself. CONCLUSION: Recombinant protein rMBP-NAP might be a novel antigen for vaccine development against H pylori.

[Establishment of segregating inbred strain of Yuyi hairless mice and its monitoring of genetic characteristics].

Using brother-sister inbreeding with forced heterozygosity to breed a new segregating inbred strain which carry mutant hairless gene. Then, genetic monitoring was conducted by the skin grafting test, coat color test and biochemical marker analysis, and its basic biological characteristics were studied with corresponding methods. The Results are that the Yuyi Hairless Mice (YYHL) with unique biological characteristics have been bred successfully and have progressed to 30th generation since 1991. Thirteen biochemical markers loci on nine chromosomes coding biochemical markers measured with electrophoresis were all homogenous. The skin grafting test showed that no dropping graft was found during 100 days after transplanting, implying the YYHL was of isohistogeneicity. Analysis of coat color genes indicated that the hair color of first generation hybrid crossed between YYHL and DBA/2 was all agouti suggesting that the coat color genes of the YYHL were homogenous. The gene type is AABBccDD. All these showed that the YYHL have been an inbred strain reaching the international standards.