Splenic erythroblasts were obtained from mice during the acute disease caused by anemia-inducing virus (FVA). They were cultured in a medium containing EPO, BSA and so on. We studied their biomechanical and hemorheolo...Splenic erythroblasts were obtained from mice during the acute disease caused by anemia-inducing virus (FVA). They were cultured in a medium containing EPO, BSA and so on. We studied their biomechanical and hemorheological behavior after 12 h, 24 h and 48 h. The results showed obvious changes in their electrophoretic mobility, osmotic fragility, membrane fluidity and membrane viscoelastic properties with the development of erythroblast. The changes were associated with the interactions of the protein and lipid and the elements of the membrane.展开更多
SARS-CoV-2 has become a global pandemic threatening human health and safety.It is urgent to find effective therapeutic agents and targets with the continuous emergence of novel mutant strains.The knowledge of the mole...SARS-CoV-2 has become a global pandemic threatening human health and safety.It is urgent to find effective therapeutic agents and targets with the continuous emergence of novel mutant strains.The knowledge of the molecular basis and pathogenesis of SARS-CoV-2 in host cells requires to be understood comprehensively.The unknown structure and function of nsp2 have hindered our understanding of its role in SARS-CoV-2 infection.Here,we report the crystal structure of the N-terminal of SARS-CoV-2 nsp2 to a high resolution of 1.96?.This novel structure contains three zinc fingers,belonging to the C2 H2,C4,and C2 HC types,respectively.Structure analysis suggests that nsp2 may be involved in binding nucleic acids and regulating intracellular signaling pathways.The binding to single or double-stranded nucleic acids was mainly through the large positively charged region on the surface of nsp2,and K111,K112,K113 were key residues.Our findings lay the foundation for a better understanding of the relationship between structure and function for nsp2.It is helpful to make full use of nsp2 as further research and development of antiviral targets and drug design.展开更多
OBJECTIVE: To investigate whether the decrease in expression of interleukin-2 (IL-2) after trauma is associated with changes in DNA binding activity of nuclear factor of activated T cells (NFAT) and activator protein-...OBJECTIVE: To investigate whether the decrease in expression of interleukin-2 (IL-2) after trauma is associated with changes in DNA binding activity of nuclear factor of activated T cells (NFAT) and activator protein-1 (AP-1). METHODS: Mice with closed impact injury with fracture in both hind limbs were adopted as the trauma model. Spleen lymphocytes were isolated from traumatized mice and stimulated with Con-A. Culture supernatants were assayed for IL-2 activity, and total RNA was extracted from spleen lymphocytes and assayed for IL-2 mRNA. DNA binding activity of NFAT and AP-1 were measured by electrophoretic mobility shift assay (EMSA). The expression of c-Fos, c-Jun and JunB proteins was determined by the Western blot analysis. RESULTS: DNA binding activity of NFAT and AP-1 gradually decreased to a minimum of 41% and 49%, respectively, of the control on the 4th day after injury, which was closely followed by the decline in IL-2 activity and IL-2 mRNA. A decrease in the expression of c-Fos on the 1st and 4th day after trauma had no significant effect on c-Jun expression; the increase in expression of JunB was only on the 1st day after injury. CONCLUSION: Decreased IL-2 expression is, at least in part, due to a decline in the activation of NFAT and AP-1 in traumatized mice. The decline in DNA binding activity of NFAT and AP-1 is partly due to a trauma-induced block in the expression of c-Fos.展开更多
基金This work was supported by the National Natural Science Foundation of China (Grant No. 39830110).
文摘Splenic erythroblasts were obtained from mice during the acute disease caused by anemia-inducing virus (FVA). They were cultured in a medium containing EPO, BSA and so on. We studied their biomechanical and hemorheological behavior after 12 h, 24 h and 48 h. The results showed obvious changes in their electrophoretic mobility, osmotic fragility, membrane fluidity and membrane viscoelastic properties with the development of erythroblast. The changes were associated with the interactions of the protein and lipid and the elements of the membrane.
基金supported financially by National Key Research and Development Program of China(2018YFE0113100)National Natural Science Foundation of China(31872713)。
文摘SARS-CoV-2 has become a global pandemic threatening human health and safety.It is urgent to find effective therapeutic agents and targets with the continuous emergence of novel mutant strains.The knowledge of the molecular basis and pathogenesis of SARS-CoV-2 in host cells requires to be understood comprehensively.The unknown structure and function of nsp2 have hindered our understanding of its role in SARS-CoV-2 infection.Here,we report the crystal structure of the N-terminal of SARS-CoV-2 nsp2 to a high resolution of 1.96?.This novel structure contains three zinc fingers,belonging to the C2 H2,C4,and C2 HC types,respectively.Structure analysis suggests that nsp2 may be involved in binding nucleic acids and regulating intracellular signaling pathways.The binding to single or double-stranded nucleic acids was mainly through the large positively charged region on the surface of nsp2,and K111,K112,K113 were key residues.Our findings lay the foundation for a better understanding of the relationship between structure and function for nsp2.It is helpful to make full use of nsp2 as further research and development of antiviral targets and drug design.
文摘OBJECTIVE: To investigate whether the decrease in expression of interleukin-2 (IL-2) after trauma is associated with changes in DNA binding activity of nuclear factor of activated T cells (NFAT) and activator protein-1 (AP-1). METHODS: Mice with closed impact injury with fracture in both hind limbs were adopted as the trauma model. Spleen lymphocytes were isolated from traumatized mice and stimulated with Con-A. Culture supernatants were assayed for IL-2 activity, and total RNA was extracted from spleen lymphocytes and assayed for IL-2 mRNA. DNA binding activity of NFAT and AP-1 were measured by electrophoretic mobility shift assay (EMSA). The expression of c-Fos, c-Jun and JunB proteins was determined by the Western blot analysis. RESULTS: DNA binding activity of NFAT and AP-1 gradually decreased to a minimum of 41% and 49%, respectively, of the control on the 4th day after injury, which was closely followed by the decline in IL-2 activity and IL-2 mRNA. A decrease in the expression of c-Fos on the 1st and 4th day after trauma had no significant effect on c-Jun expression; the increase in expression of JunB was only on the 1st day after injury. CONCLUSION: Decreased IL-2 expression is, at least in part, due to a decline in the activation of NFAT and AP-1 in traumatized mice. The decline in DNA binding activity of NFAT and AP-1 is partly due to a trauma-induced block in the expression of c-Fos.
基金The project supported by National Project of Advanced Research of China (No.2004CCAO7500)AFCRST(Association Franco-Chinoise pour la Recherche Scientifique et Technique)
