Abstract:Systems biology is a newly-emerging interdisciplinary field of study that follows on the foundation of genomics and proteomics. As such, it constitutes an important area of research for the 21st century. Recently, independent institutions have been established for systems biology. In this field of research, experimental and computational methods are integrated to understand complex biological systems. High-throughput methods of genomics and proteomics provide large amounts of data for the development of systems biology. Computational biology has become an indispensable and compelling tool for data processing, modeling, and theory analysis. In application, systems biology represents the direction for future advancements in medicine and disease control.

Abstract:Some intrinsic ESC-specific markers, cytokines and extracelluar matrix in the microenvironment compose of a complex network to co-regulate ESC self-renewal. The molecular mechanism of signal network maintaining ESC self-renewal was investigated by studying the ESC-specific markers, such as Oct-4 and Nonog recently. Moreover, ESC signal pathways, just like LIF-STAT3, Wnt-β-catenin and BMP-Id ,were further deeply studied. In conclusion, the most important key to maintain ESC self-renewal is the balance among the content of various cytokines, extracelluar matrix, and expressing quantity of intrinsic ESC-specific markers by different signal stimulators.

Abstract:Many investigations revealed that, because of different biophysical and biochemical properties of different ingredients of plasma membrane, they are phase-separated into local domains. Different domains may have different functions. In the past few years, a special kind of cholesterol, sphingolipids, receptor and signal molecules-rich liquid-ordered domain，lipid rafts，which have been implicated in processes as diverse as signal transduction, cell sort, endocytosis and cholesterol trafficking, have been paid much attention. Hereupon, primary progress has been made in fundamental investigations on the structure and function of lipid rafts.

Abstract:Proteolysis of cellular proteins is carried out by a complex cascade of enzymes and displays a high degree of specificity towards its numerous substrates. Discovery and studies of the ubiquitin-proteasome pathway reveal that the specific protein degradation is a highly complex, temporally controlled and tightly regulated process which plays important roles in a broad array of basic cellular processes. A defective protein, which binds poly-ubiquitin chain (so-called “degrading label”) through its ε-amino group of Lys residue, is degraded in the proteasome. This selectively cellular elimination of defective protein is a key process in protein kinesis.

Abstract:Richard Alex and Linda Buck win this year’s Nobel Laureates in Physiology and Medicine. They discovered a lage gene family in olfactory system that give rise to an equivalent number of olfactory receptor type. These receptors are located on the olfactory neuron in the nasal epithelium and to detect different odorant molecules.

Abstract:Photocatalytic titanium apatite filter (PTAF) is a new material that has been reported to have an ability to absorb and inactivate bacteria. The inactivation effect of PTAF on serious acute respiratory syndrome coronary virus (SARS-CoV) was tested. The results showed that PTAF filter inactivated/decomposed SARS CoV up to 99.99％ after 6 h interaction under the condition of non-UV irradiation. However, under the condition of UV irradiation, PTAF and HAF both were able to inactivate/decompose SARS CoV completely. The study has provided the first evidences that PTAF could inactivate SARS-CoV virus, suggesting that the PTAF material will be applied for the prevention of SARS-CoV as well as other viruses.

Abstract:The function of the neuronal microtubule-associated protein MAP1b is regulated by the degree of its phosphorylation, which is controlled in turn by activities of protein kinases and protein phosphatases (PP). To investigate the role of PP in the regulation of phosphorylation of MAP1b, okadaic acid and cyclosporin A were used to selectively inhibit PP2A and PP2B activities, respectively, in metabolically competent rat brain slices. The alterations of phosphorylation levels at mode Ⅰ sites of MAP1b were examined by Western blots using a phosphorylation-dependent MAP1b antibody 522 that specifically recognizes MAP1b phosphorylated at mode Ⅰ sites. The inhibition of PP2A, but not PP2B, was found to induce a marked increase in phosphorylation of MAP1b. Immunohistochemically, MAP1b was found ubiquitously in neuronal cell bodies and processes. A marked increase in neuronal staining in okadaic acid-treated tissue was observed with antibody 522 to the phosphorylated MAP1b. These results suggest that PP2A is the major PP that participates in regulation of the phosphorylation of MAP1b at the mode Ⅰ phosphorylation sites.

Abstract:Mouse canstatin is a C-terminal globular non-collagenous domain of type Ⅳ collagen α2 chain, which previously showed anti-angiogenic activity. To investigate in vivo angiostatic effects on chick chorioallantoic membrane(CAM) by recombinant mouse canstatin N-fragment(1～95aa), the cDNA for N-fragment of mouse canstatin, obtained from a cloning vector pMD18T-mCan by PCR, was introduced into an expression vector pET30a(+) to construct prokaryotic expression vector pET-mCanN. N-fragment of mouse canstatin efficiently expressed in E.coli BL21(DE3) after IPTG induction was monitored by SDS-PAGE and by Western blotting with an anti-hexahistidine tag antibody. The expressed N-fragment of mouse canstatin, mainly as inclusion bodies, accounted for approximately 18% of the total bacterial proteins as estimated by densitometry. The inclusion bodies were washed, lysed and purified by the nickel affinity chromatography to a purity of 92%. The refolded N-fragment of mouse canstatin was tested on the chicken embryo CAMs, and a large number of newly formed blood vessels were significantly regressed. It is concluded that N-fragment derived from mouse canstatin is an effective inhibitor of angiogenesis of the chicken embryo in a dose-dependent manner through CAM assay and a promising candidate for the treatment of cancer, suggesting that these novel findings may add to the understanding of anti-angiogenesis effects of the N-fragment of mouse canstatin.

Abstract:The osteoblasts were expanded in large-scale by microcarrier suspension culture in rotating wall vessel bioreactor(RWV), then the biological functions of the cells were detected by histomorphometry and the cells were seeded at 2×10⁶ cells/ml and 1×10⁶ cells/ml onto scaffolds respectively to culture for 2 weeks. The biological properties of the fabricated bone tissue were detected by inverted microscope, scanning electron microscope (SEM), alkaline phosphatase (ALP), von-Kossa staining on mineralized nodules and AO/EB fluorescence staining. Meanwhile the cells' metabolism of nutrients was monitored and analyzed during the whole culture process. The bone tissue fabricated in RWV with two different seeded cell densities grew well. Osteoblasts in the scaffolds secreted much collagen fibers and formed mineralized nodules and new osteoid tissue. It can be conclueled that: With the stress stimulation inside the fluid in the RWV, the active expression of ALP can be increased, the formation of mineralized nodules can be accelerated. The rapid proliferation and differentiation of osteoblasts are possible and the three-dimensional fabrication of engineered bone could be realized.

Abstract:In order to examine molecular markers of dysplasia progression, improved deoxycholate-trichloroaetic acid (DOC-TCA) extracted total protein of bronchial epithelial. After profiling squamous dysplasia versus invasive carcinoma of bronchial epithelium using two-dimensional electrophoresis, the patterns were compared and differential proteins were found with ImgeMaster software and Student t-test (P＜0.05). The selected differential protein-spots were identified by peptide mass fingerprint (PMF) based on matrix-assisted laser desorption /ionization time-of -flight mass spectrometry (MALDI-TOF-MS) and database searching. The average spots for dysplasia and invasive carcinoma were (1 273.00±43.31) and (1 326.00±66.63), respectively. After matching, the number of spots of differentially expressed proteins between the dysplasia and invasive cancer tissues were (56.00±8.96). Thirty eight differential proteins were identified, some of which are known to be involved in regulating the processes of proliferation, differentiation and tumorigenesis. In particular, c-Jun was up-regulated in invasive cancer compared with dysplasia, and murine double minute gene 2 (Mdm2) was only expressed in invasive cancer. But truncated EGFR (epidermal growth factor receptor) is reduced in invasive cancer. The subsequent immunohistochemical analysis of human tissues biopsies also showed a similar expression pattern. Therefore there are differentially expressed proteins during malignant transformation of bronchial epithelium from dysplasia to cancer. These differential proteins probably take part in carcinogenesis in different forms. The similar results of mass spectrometry and immunohistochemistry illustrated the use and reliability of comparative proteomics to screen relevant molecular markers of carcinogenesis.

Abstract:An open reading frame (ORF) was annotated as putative trehalose synthase in Deinococcus radiodurans sequenced genome, which has been found in GenBank database through amino homology blast base on combination of bioinformatics. Blasting against the database indicates that amino acid sequence of this ORF has less than 60% homology with the reported terhalose synthases. The function, which was identified by expressing this ORF in Escherichia coli, proves this ORF is a novel trehalose synthase gene. Using the 30% maltose as substrate, about 65% maltose can be converted into trehalose by this enzyme. Recombinant enzyme showed optimal activity at pH 7.0 and 30℃ when it converts maltose into trehalose.

Abstract:In order to clarify the role of peroxisomal fatty acid β-oxidation and D-bifunction protein (D-BP) in lipid metabolism disorder of diabetes mellitus(DM), the number of peroxisomes by electronic microscope and the activities of major enzymes involved in peroxisomal β-oxidation in livers from STZ-induced diabetic and normal rats are compared respectively. Catalase and D-BP protein level was determined by Western blot. In the livers of STZ-induced diabetic rats, the peroxisomes proliferated and showed some morphological changes, while the protein amount and activity of catalase significantly increased. Although the activities of acyl-CoA oxidase, L-3-hydroxyacyl-CoA dehydrogenase and fatty acid β-oxidation of peroxisome in the diabetic rat liver were significantly increased, the protein amount and activity of D-BP in the diabetic rat liver was decreased compared to control rats. The relationship between decreased D-BP activity and lipid metabolism disorder in DM was also discussed.

Abstract:DPD enzyme, encoded by the DPYD gene, is the major rate-limiting enzyme in the metabolism of the anti-cancer drugs. And it exists substantial inter-individual variations in its enzymatic activity. It was shown that mutant alleles of DPYD that encoding an inactive/decreased enzyme are largely caused by SNP (single nucleotide polymorphism) in the gene. Detection of the SNPs is the basis for the prediction of drug-response and realization of individualized therapeutic regimen for patients. For this reason an oligonucleotide microarray for genotyping 6 known SNPs of DPYD gene was optimized, and the genotyping standard for this microarray was fabricated. The microarray system was used to detect the mutant allelic frequency of DPYD in cancer patients (112 individuals), nephrotic patients (83 individuals) and healthy subjects(45 individuals). In the studied groups, the average frequencies for the mutant alleles of DPYD^*5 and DPYD^*9 are 11.25% and 32.08% respectively. No mutant alleles of DPYD^*2, ^*3, ^*4, ^*12 were found. And there is no significant difference (P＞0.05) in the mutation incidence in different subject groups or sex groups. The SNPs was shown to have no significant association with the disease and sex. The genotyping results of 20 samples were tested by direct sequencing, the genotyping results of 19 samples by miroarray were conformed with the direct sequencing. The allelic frequencies of DPYD^*5 and DPYD^*9 is high in the studied groups, quick and accurate detection of them can be achieved by using DNA microarray.

Abstract:The ubiquitin(UB) gene of Bombyx mori nuclear polyhedrosis virus Zhenjiang strain (BmNPV-ZJ) was cloned and sequenced. Sequencing analysis shows that the BmVUB gene, which contains 234 nucleotides encoding 77 amino acids, contains a conservative HTH, a conservative LRLRGG and four conservative functional sites: Lys-29,Cys-48,Cys-63,Gly-76 which play important roles in ubiquitin-proteasome complex formation .It also shows that the C-terminal amino acid was redundant which locate at the downstream of conservative Gly-Gly proteinase cleavage signal sequence which characterizes as Gly-Gly-X（X was hydrophobic amino acid）. The BmVUB gene was induced and highly expressed in E.coli BL21. The results of gel scanning and Bradford protein assay show that the BmVUB protein was about 9 ku and the yield consists of 50 percent of total bacterial protein. The concentration of purified BmVUB protein was 1.03～2.46 g/L. The high titer antibody was obtained from rabbits immunized with the (His)₆- BmVUB fusion protein and ELISA shows that the titer of antibody was over 3.2×10^-5. Peptides binding ubiquitin were obtained from phage displayed peptide library using BmNPV-ZJ ubiquitin purified with His-affinity chromatography as a ligand. Five short peptides were identified which displayed obvious biological activity. Peptide VAPHHAYAPMRT could regulate the cell proliferation and further more this function which depends on the concentration variation, namely low concentration could promote the cell proliferation, whereas high concentration will inhibit the proliferation.

Abstract:The electrophoretic microchip fabricated by MEMS technology is successfully used to finish the electrophoresis process. The albumen-detected technology is based on the UV- absorption principle. The utilization of the procedural control makes the experimental process convenient and exact, and therefore improves the separation efficiency and detection sensitivity. It is proved that the pinched injection can separate the mixed proteins efficiently in this on-chip capillary.