Two-component signal transduction system (TCS) exists extensively in prokaryotic cell ,which plays a key role of regulation in the growth ,differentiation ,metabolism ,virulence ,persistence ,and pathogenicity .PhoPR two-component signal transduction system ,as one of two-component systems ,is the most basic and the most importantly sensitive to the envi-ronmental changes and makes corresponding certain reaction system adapt to changes in the host microenvironment .Therefore , PhoPR TCS which is an important regulatory system of Mycobacterium tuberculosis (MTB) to adapt to environmental change has been increasing concern ,even PhoPR TCS is becoming the new front-burner issue in the pathogenesis of M TB regulation of research .

Proteasome pathway is another major pathway of protein degradation in addition to lysosome in eukaryotic cell ,which involved a number of physiological functions regulation in cell .Prokaryotic ubiquitin-like protein was found in My-cobacterium tuberculosis in 2008 .With the effect of co-factor Dop ,PafA and Mpa ,Pup can mark a variety of protein ubiquitina-tion followed by importing them into proteasomal degradation .The target protein of Pup-proteasome system like FabD ,PanB , Ino1 ,Icl ,SodA ,and MtrA are involved with metabolism ,signal transduction pathways ,virulence factors ,pathogenicity and the persistence of bacteria in the host cell .Proteasome inhibitor make the function of proteasome restricted and the accumula-tion of Pup’s labeled substrate result in changes in the expression of gene indirectly ,which impacted the ability of resistance to outside pressure and the pathogenicity of Mycobacterium tuberculosis . The finding Pup-proteasome system reveals a novel mechanism of protein degradation in prokaryotes ,which is expected to become a new target of treatment of anti-TB drugs . Here ,we summarize the progress on the Pup-proteasome system in Mycobacterium tuberculosis .

Objective To screen differential Mycobacterium tuberculosis genes between Xinjiang clinical strains and H37Rv by suppression subtractive hybridization( SSH), and to analyze the function of these specifically pathopoiesis genes. Methods Both M. tuberculosis Xinjiang clinical strains and H37Rv as tester and driver each other, most identical genome was drived whereas some distinctive genes was re-mained and enriched by utilization SSH technique. Meanwhile through inserting differential genes to E. coli all of sequences that we have cloned were determined by BLAST in GenBank. The function of differential genes between M. tuberculosis H37Rv and Xinjiang clinical strains were analyzed. Results We cloned and analyzed six different DNA fragments that only existed in Xinjiang clinical strains. One is the fragment of a gene ceding monooxygenase, flavin-binding family identified by Glimmer2. One fragment belongs to acyl-transferase family protein. One for aminotransferase, class Ⅱ, acyl carrier protein. One fragment belongs to chromosomal replication initiator protein DNA and one for M. tuberculosis paralogous family 11-pyridoxamine 5'-phosphate oxidase-related. Meanwhile, we cloned ten DNA fragments only in H37Rv. Conclusion SSH technique can efficiently screen differential genes in M. tuberculosis in Xinjiang clinical strains. They are possible key genes that M. tuberculosis survive and fortify virulence in mal-environment as same as their ho-mogenic genes, such as enhanced adsorbability in wall-held protein, counteracted digestion by nitro-oxygen-ase, elevated composition capability in the acyhransferase, control chromosomal replication initiator protein, synthesized aminotransferase acyl cartier protein and pyridoxamine 5'-phosphate oxidase.

AIM:To detect the drug-resistance mycobacterium tuberculosis by using DNA microarray hybridization.METHODS: DNA microarray for detecting drug-resistance of mycobacterium tuberculosis was prepared; Clinical isolated strains were cultivated and their drug-resistance sensitivity was detected. The genome DNA of mycobacterium tuberculosis was prepared and the drug-resistance genes of the mycobacterium tuberculosis were amplified by PCR. Then the gene chip was hybridized, washed, detected and analyzed. RESULTS: Results of cultivating mycobacterium tuberculosis and detecting the drug-resistance sensitivity: one strain was drug-sensitive; four strains were multi-drug-resistant; The detecting results of the drug-resistance was consistent with the results of diagnosis therapy of the 5 clinical patients. The detecting results of gene chip confirmed the above facts. CONCLUSION: Detecting drug-resistance mycobacterium tuberculosis by the gene chip is precise, fast and highly-efficient.

Objective To observe the effect of Vascular Endothelial Growth Factor(VEGF) to the expression in hepatoma cells affected by TGF-?1 and hopxia. Methods HepG2 cells were cultured in vitro, and treated with different doses of TGF-?1 and Cobalt chloride hexahydrate(CoCl2), or with TGF-?1 and CoCl2. The change of VEGF protein and mRNA was detected by immunohistochemistry and semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Results Immunohistochemistry and RT-PCR showed that the expression of VEGF protein and mRNA were significantly higher in TGF-?1 groups or CoCl2 groups than that of control group(P

Objective:In this study,we examined the HLA-DPB1 alleles in patients with tuberculosis,and health individuals attempt to investigate the association between the polymorphism of HLA-DPB1 gene and pulmonary tuberculosis in Han population in Shihezi area in Xinjiang uygur autonomous region of China.Methods:High-resolution typing of DPB1 was performed by the sequence-based typing ( SBT) method using the SBT-HLA-DPB1 generic DNA typing kit.Results:In the controls ,17 HLA-DPB1 alleles were ob-served,the HLA DPB1*0501 (28.1%) and HLA DPB1*0201(27.6%) frequency was significantly higher than other sites ,the first and second respectively.The frequency of HLA-DPB1* 0201 was observed significantly increased in patient group compared with control group ( P<0.05 );the frequency of HLA-DPB1* 0501 was observed significantly decreased in patient group compared with control group ( P<0.05 ).Conclusion: The gene frequencies of HLA-DPB1 in Xinjiang Shihezi Han population are roughly in consistence with other northern Chinese Han population;the HLA-DPB1*0201 may be the protective factor to pulmonary tuberculosis , and HLA-DPB1*0501 may be susceptible to pulmonary tuberculosis in Han population from the Xinjiang uygur autonomous region of China.

We studied the effect of the Mycobacterium tuberculosis prokaryotic ubiquitin-like protein-proteasome system on mono-resistant to rifampin resistance to M.tuberculosis.A resazurin-based assay was employed to evaluate minimum inhibitory concentration (MIC) and comparative research on mono-resistant to rifampin MTB with Pup,Dop,PafA,Mpa genes expression and deletion of the difference.Above testing strains,respectively,carbonyl cyanide chlorobenzene hydrazone (CCCP),reserpine (RP),verapamil (VP)and chlorpromazine (CPZ) were tested.We compared and analyzed the change of rifampicin MICs on the various strains.Compared with rifampin resistant MTB,overexpression of Pup,Dop,PafA and Mpa genes were able to make monorifampicin of M.tuberculosis to enhance resistance to rifampin.Deletion of Pup gene,Mpa gene,Dop gene,PafA gene significantly decreased the resistance to rifampicin alone MTB,and the P value was ＜0.05.Results indicated that 4 kinds of efflux pump inhibitors can reduce the degree of rifampin MIC in different strains.Through the factorial analysis,there were some interactions between MTB and PPS efflux pump inhibitors,and the P value was ＜0.05.MTB PPS has influence on mono-rifampin resistance to MTB and it may regulate the efflux pathway related protein to influence its resistance.

AIM:To investigate the effect of inhibiting Mcl-1 gene expression on apoptosis of mouse peritoneal macrophages infected with different virulence of Mycobacterium tuberculosis using a technique of RNA interference .METH-ODS:The BALB/c mice were infected with prepared bacterium of the virulence strains of Xinjiang , H37Rv, H37Ra and BCG.Mcl-1-shRNA was applied to the mouse model of infection , and the control groups were set up .On 1 d, 3 d, 5 d and 7 d, the mouse peritoneal macrophages were collected .The expression of Mcl-1 at mRNA and protein levels was deter-mined by real-time PCR and Western blot .The apoptotic rate of peritoneal macrophages was analyzed by flow cytometry . RESULTS:The expression of Mcl-1 at mRNA and protein levels was up-regulated in the peritoneal macrophages from the mice infected with different virulence of Mycobacterium tuberculosis, and the cells from the mice infected with virulence strains of Xinjiang and H37Rv expressed higher level of Mcl-1 than the uninfected control cells (P<0.05).The expres-sion of Mcl-1 at mRNA and protein levels was reduced by RNA interference as compared with control group ( P<0.05 ) . Inhibition of Mcl-1 expression induced apoptosis of peritoneal macrophages in the mice .CONCLUSION: The Mcl-1 ex-pression at mRNA and protein levels in mouse peritoneal macrophages infected with different virulence of Mycobacterium tu-berculosis was effectively suppressed by Mcl-1-shRNA, which can induce macrophage apoptosis .

Objective To study the expressions of myeloid cell leukemia-1 (Mcl-1 ) gene in mouse macrophages Raw264.7 and human macrophages THP-1,to screen out the cell lines with high levels of expression as the experimental cells,and based on the screening results to construct the short hairpin RNA(shRNA)eukaryotic expression plasmid targeting mice Mcl-1 gene for transfection and further screen out the shRNA expression plasmid with the most obvious effect in silencing Mcl-1 gene.Methods Semi-quantitative PCR method was used to detect the expression of Mcl-1 mRNA in the two kinds of macrophages.Western blotting was adopted to detect the expressions of Mcl-1 proteins in the two kinds of macrophages.Three different gene loci for Mcl-1 shRNA fragments were designed with small molecules interfering RNA (siRNA)software.Eukaryotic expression plasmid Mcl-1 shRNA 1-3 carrying the shRNA fragments was constructed by a company.And the eukaryotic expression plasmid vector was transfected into scavenger cells Raw264.7 mice via through the liposome.The transfection results 24 h and 48 h after transfection were observed under the inverted fluorescence microscope;Mcl-1 mRNA and protein expression were detected by real time quantitative PCR and Western blot,respectively.Results The relative expression levels of Mcl-1 mRNA and protein in mouse macrophages Raw264.7 were significantly higher than those of human macrophages (P <0.05).The shRNA expression vector constructed within 24 h and 48 h could decrease Mcl-1 mRNA and protein levels in Raw264.7 cells,especially with the most obvious silencing effect at 48 h.The 48-h transfection group differed significantly from normal group,liposome group and negative control group (P <0.05).Compared with Mcl-1shRNA1and Mcl-1shRNA2,Mcl-1shRNA3 had the strongest effect in silencing Mcl-1mRNA and protein.Conclusion We have successfully screened out experimental Raw264.7 cells and Mcl-1 shRNA eukaryotic expression plasmid which has an obvious silencing effect targeting on Mcl-1 in mice macrophages Raw264.7.

Objective:To transfect Mcl-1shRNA into Raw264.7 cells,and screen out specific shRNA eukaryotic expression plasmids with the most significant effect of silent Mcl-1 gene to figure out the effect of shRNA on Mcl-1 expression in murine macrophage cell line Raw 264.7.Methods: Specific shRNA was transfected into murine macrophage cell line Raw 264.7 via lipofectamine.Semi-quantitative RT-PCR and Western blot were respectively employed to test the changes in Mcl-1 mRNA level and Mcl-1 protein expressions 24 h and 48 h after the transfection ,and the silencing effects of the three pairs of specific shRNA fragments corresponding to different sites were analyzed.Results: Specific shRNA fragments at 24 h and 48 h could effectively reduce Mcl-1 mRNA and protein level ,with higher silencing effects than those of the normal group ,the lipofectamine group and the negative control group.There were statistically significant differences among them ( P<0.05 ).Among the three pairs of specific shRNA fragments corre-sponding to different sites ,Mcl-1 shRNA3 showed the most significant inhibiting effect on Mcl-1 mRNA and proteins.Conclusion:RNA interference can downregulate the level of Mcl-1 mRNA in murine macrophage cell line Raw 264.7 and greatly downregulate the expression of Mcl-1protein.Specific shRNA eukaryotic expression plasmids with the most significant effect of silent Mcl-1 gene have been screened out successfully.