ABSTRACT
Objective To screen and verify the proteins interacting with phosphorylation cluster of DNA dependent protein kinase catalytic subunit((DNA-PKcs) by yeast two-hybrid assay.Methods To know the proteins interacting with DNA-PKcs phosphorylation cluster,yeast two-hybrid assay was applied to screen the cDNA library of human hepatic tissue with a previously constructed plasmid pGBKT7-DPC.The positive clones were further identified by PCR,rotary validation and sequence analysis.Then the eukaryotic expression vectors of the bait protein and screened positive clone proteins were constructed and transfected into human embryonic kidney 293T cells to detect whether the proteins could been expressed correctly.At last,the bait protein and screened positive clone proteins were co-transfected into 293T cells and protein interaction was detected with Co-Immunoprecipitation (Co-IP) assay.Results After two rounds of screening using the yeast two-hybrid assay,12 candidate clones were obtained.Then 7 clones with different insert fragments were identified by PCR,and 3 positive proteins interacted with DNA-PKcs phosphorylation cluster were further verified by rotary validation.Sequencing analysis demonstrated that these 3 proteins were MBNL1,SIK2 and YY1AP1,respectively.Accordingly,the eukaryotic expression vectors of bait protein and 3 positive clone proteins were constructed successfully and expressed correctly in 293T ceils.Finally,the Co-IP assay confirmed that these 3 positive clone proteins could interact with DNA-PKcs phosphorylation cluster.Conclusions Proteins interacting with DNA-PKcs phosphorylation cluster are successfully screened and identified.
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Objective To study the expression of tumor necrosis factor alpha (TNF-α) in the intestine of mice irradiated by neutron and γ rays.Methods 350 male BALB/c mice were irradiated with neutron and γ rays of different doses, and sacrificed at 6 and 12hours, 1, 2, 3, 4, 5, 7, 10, 14, 21 and 28 days after irradiation.The TNF-α in the mice intestinal tissue was detected by means of immunohistochemistry and image analysis.Results In normal control mice, TNF-α was expressed in the cytoplasm of macrophages in intestinal villus interstitium, submucosa and lymph tissue.After 2.5Gy neutron radiation, TNF-α was decreased progressively within 2 days, increased obviously in macrophages and crypt cells during 3rd～7th day, reached the peak at 5th day and recovered to normal level at 14th day and TNF-α was decreased progressively within 4 days after 4.0 and 5.5Gy neutron and 12Gy ray irradiation.TNF-α was increased obviously in 6～12 hours, decreased at 1st day, increased at 2nd～5th day, peaked at 3rd day and recovered at 10th day after 5.5Gy ray irradiation.Conclusion Neutron and ray radiation induce different expression profile of endogenous TNF-α in small intestine, which may be related with the pathologic courses of irradiation-induced damage and repair of intestine.
ABSTRACT
OBJECTIVE To study the pathogenicity of the Vibrio fluvialis isolated from the coastal seawater.METHODS Virulence experiment group:22 Kunming mice were divided into four subgroups in random:V.fluvialis was injected into abdominal cavity in the test subgroup.And Staphylococcus aureus and Escherichia coli were injected into the positive control subgroups,separately and aseptic physiological saline was injected into the negative control group.Wound infection group:22 SPF mice were divided into four supgroups in random after their legs were injured:the experimental supgroup(soaked in artificial seawater with V.fluvialis);the positive control groups(with S.aureus and E.coli,separately);the negative control group(soaked in aseptic artificial seawater).The general condition,blood routine,blood culture,organ culture and wound secretion culture of the mice were observed.The pathological analysis of the mice was taken after sacrifice on the 3rd day.RESULTS In virulence experiment group,among all the 7 mice′s blood culture of V.fluvialis supgroup,5 mice were found V.fluvialis positive after 12 h injection,and 2 mice kept on positive until 24 h.In wound infection group,pathological examination showed there were a large number of neutrophils distributed over the striated muscle of the injured sites and cellulitis formed.CONCLUSIONS The V.fluvialis isolated from the sea water has pathogenicity,and can cause wound) infection and septicemia when the concentration reached 106 CFU/ml.