Abstract:Bacteriorhodopsin (bR) is the sole protein in the purple membrane of Halobacterium salinarium, which functions as proton pump, charge separation and photochromism. The chromophore retinal is covalently attached to Lys 216 via a protonated Schiff base. Upon illumination, the all-trans to 13-cis isomerization of the retinal results in deprotonation of the Schiff base followed by alterations in protonatable groups within bacteriorhodopsin. The changed force field induces changes, even in the tertiary structure, which facilitate and warrant the vectorial proton translocation.

Abstract:Integrins are receptors of extracellular matrix, which are commonly present on the cell surface of animal. Integrin-mediated adhesion is involved in many aspects of cell activities. Recent studies have shown that there may be integrin-like proteins in plant cells. The advance in identification, localization, composition, structure, gene and possible function of integrin-like proteins were reviewed.

Abstract:Signal transduction of reactive oxygen species (ROS) has been of great interest recent years. ROS may signal through oxidation or reducton of specific groups such as cystein residues or redox-active iron center on certain biomolecules, or through modulating cellular redox status in different cell types. There were many documents indicating that signal pathway of ROS associate with some well-known regulating molecules as following: protein tyrosine kinase (PTK), protein kinase C (PKC), mitogen activated protein kinase (MAPK), nuclear factor NF-κB, AP-1 and Ca^2＋ ,cGMP. Although great advances of signal transduction of reactive oxygen species has been taken in recent years，there are many important questions remained to be answer in future.

Abstract:In recent years,three proteins that have high homology with protein 4.1 in red blood cell have been obtained.All of them involve three functional domains,membrane-binding domain,spectrin-actin binding domain and carboxyl terminal domain. Moreover,protein 4.1 is related to mitosis and the formation of the neural synapse besides that it plays an important role in maintaining the normal physical and physiological properties of the cell membrane.

Abstract:LIM-homeodomain transcription factor (LIM-HD) regulated expression of genes that pattern the body and generate cell specificity during development in invertebrates and vertebrates. LIM-HD proteins are themselves regulated by both intramolecular and intermolecular interactions mediated by the LIM domains. LIM domains positively regulate LIM-HD activity by promoting protein-protein interactions that allow cooperative binding to regulatory regions of tissue-specific promoters. They also negatively regulate LIM-HD activity, possibly by preventing HD association with DNA. Interaction of LIM domains with other proteins relives this interference, permitting DNA binding and providing a mechanism for refining LIM-HD activity.

Abstract:Toll signal transduction pathway plays a critical role in development as well as in innate immune responses in Drosophila. Positional cloning work proceeded in mice recently has revealed that Lps encodes the Toll-like receptor 4 (TLR4) of mammals, which functions as the transmembrane component of LPS receptor complex. In contrast, TLR2, a receptor closely related to TLR4, makes no contribution to LPS induced signaling. The discovery of TLR4 has greatly promoted understanding on the LPS signal transduction pathway.

Abstract:The most ancient host defense system found in mammals, insects and plants are mediated by Toll-like receptors (TLRs) and its associated signaling pathways of NK-κB. Signaling pathways of downstream of TLR2 or TLR4 complex which includes ligands (LPS or another), CD14 or/and MD-2 and receptor itself recruit MyD88 to activate the autophosphorylation of IRAK. The oligomerization of TNF receptor-associated factor 6 (TRAF6) is necessary to initiate the activation of NF-kB-inducing kinase (NIK) which finally leads to the activation of NF-κB via the Toll/IL-1-receptor homologous region(TIR) domain.

Abstract:As a new developmental vector system, the bacterial artificial chromosome (BAC) have several advantages: larger capacity, hereditary stability and easy handling, etc. It has been extensively used in construction of genomic library and analysis of gene function. Some new methods of analysis and modification of BAC were reviewed.

Abstract:Global minimization methods and their applications to structural molecular biology have made significant progresses in recent years. Appropriately simplified molecular docking problem is a good object of global minimization, which is now a rather active research area. Molecular docking can be divided into two categories. The detailed docking for de novo ligand design and the rough docking for known chemical database screening for drug discovery. Their demands for the global minimization algorithms are different. New stochastic and deterministic global minimization algorithms that are suitable for docking problems are briefly reviewed. Those algorithms with potential smoothing techniques seem to be promising and are worth close noting.

Abstract:During the neuro development, the guidance molecular of axon and receptor direct the axon to choose the correct way and reach the target. The structure and function of Netrin-DCC and UNC5, Semaphorin-neuropilins and plexins, Slit-robo, Eph receptor-ligand were reviewed.

Abstract:The problems existing in the conventional gene therapy involves low effectivity in virus′ targeting transduction, low speciality in integration, low effectivity in controlling the gene expression dosage and immunogenicity of virus vector. While most single gene genopathies can be cured by correct the single mutant nucleotide using gene therapy, without changing the whole gene. Chimeraplasty is a tool for site-specific gene repairing which developed rapidly in recent years. The RNA/DNA chimeric oligonucleotide can located to the exact site and repair the wrong base in situ by complementing to the host chromosome DNA sequence，and it can also be used to produce targeted mutation. It has been successfully applied in the gene therapy of some single gene genopathy and plant genetical modification. The principle, examples and prospect of this technique was described.

Abstract:The bacterial Tat protein translocation system is different with the Sec machinery which is general protein translocation system in the bacteria, but similar to ΔpH-dependent pathway used for importing chloroplast proteins into the thylakoid. This system can export proteins with a twin-arginine signal peptide bearing a consensus (S/T)-R-R-x-F-L-K motif and in the folded conformation. Moreover most of these proteins are always containing redox cofactor enzymes with relations to the bacterial anaerobic respiratory. This protein translocation system is affected by a kind of factors such as the twin arginines in the consensus motif, the hydrophobicity of h-region, sec-avoidance signal of the c-region of the signal peptide and the constitution of mature proteins. And there are four proteins (TatA,TatB,TatC and TatE) involved with this system of E.coli.

Abstract:Hox genes in mammals are the homogenetic genes of homeotic selector genes (HOM genes) in Drosophila. These genes include an encoding sequence of 183 bp, which encode a conservative protein domain of 61 amino acids. Both the nucleotide sequence of Hox gene and their position on the chromosomes are highly conservative. Hox genes are important in the regulation of spatial information during development, such as the differentiation of somites. Each somite acquires its own specialty according to its singular spatial position. Recent studies suggest that Hox genes not only influence embryonic development, but also have effects on the differentiation of adult reproductive system. They play an indispensable role in the establishment of uterine receptivity and the decidualization.

Abstract:WW domain is a coherent and compact domain generally composed of 38～40 amino acid residues. It features two tryptophan residues, and interacts specifically with proteins containing XPPXY conserved sequence. The interactions are involved in many intracellular affairs, such as non-receptor signaling, transcriptional regulation and protein degradation. Changes in these interactions will directly or indirectly interfere in normal metabolic processes and cause diseases.

Abstract:The fibroblast growth factor (FGF) family contains at least nineteen members that play important roles in embryogenesis, vascularization, neuron system growth and in development and pathological states. In order to study the mechanism of interaction of FGF/FGFR, plenty of research work was focused on the study of structure and function of FGF and FGFR. Heparin binding domain of aFGF and bFGF, and receptor binding domain of bFGF have been identified. Heparin binding domain and ligands binding domain of FGFR also were localized. Based on the research, two models of interaction of FGF/FGFR were presented and many nucleotide, saccharides and peptide inhibitors were developed. The inhibitors may play an important role in the designing of anti-cancer drug.

Abstract:Bacteriorhodopsin(bR) in the purple membrane with the function of proton pumping is an integral membrane protein, and it is a prominent prototype of the family of seven α-helical proteins. At present, bR with light-driven proton pump is one of the best char1acterized active ion-translocating proteins. It is very possible that bR will be the first membrane protein whose vectorial transport mechanism is understood at the molecular and even atomic level. The progress on the structure, photocycle and proton pump of bR in recent years are briefly introduced.

Abstract:The immunoglobulins (Igs), most of them are glycoprotein, play an important role on humoral immune. The structure, composition of oligosaccharide conjugated with protein directly effect the function of Ig. For example, abnormal oligosaccharide can result in some autoimmune diseases. The correlation between autoimmune disease mechanism such as IgAN and RA and aberrant glycosylation is given detailedly in structure, molecular mechanism, enzyme and clinic etc. And provide the theory basis on building a sensitive and specific diagnosing method.

Abstract:In order to explore the molecular mechanism of exogenous nucleic acids improving repair of irradiation-damaged intestinal epithelium, 45 mice being irradiated by γ ray were treated with 40 μg small intestinal RNA as test group, whose small intestinal specimens were collected respectively at 6 h,12 h,24 h,4 d and 8 d after treatment; 40 mice being irradiated by γ ray were treated with physiological saline as control group, whose small intestinal specimens were collected at the same interval time. Then fragments of genes expressed in test group higher than those in control group, were obtained by using LD-PCR based on subtractive hybridization. After that, these gene fragments were cloned into T vectors,and were sequenced. Obtained sequences were searched for GenBank.90 clones associated with repair of irradiation -damaged crypt cells were obtained.In test group of 6 h, higher similar sequences mainly were as follows: mRNA for heat shock protein, Nmi mRNA, Dutt1 protein, mRNA for Na,K-ATPase gamma subunit,mRNA for surface glycoprotein,Zinc finger type transcript factor,porcine growth hormone-releasing hormone gene,Homo sapiens dual specificity phosphatase,etc. In test group of 12 h, higher similar sequences were as follows: alkaline phosphatase mRNA,alkaline phosphatase 2,glkA gene, single stranded replicative centromeric gene,Homo sapiens DMBT1 candidate tumor gene, tRNA -Met gene,mouse Ig unrearranged transcribed H-chain,thyroxine-binding globulin gene,alpha-2-plasmin inhibitor gene, etc;In test group of 24 h, higher similar sequences were as follows: anti-CEA ScFv antibody heavy chain vary region,anti-DNA antibody Ig heavy chain, mRNA for Ig kappa chain region,anti-BONT/A Hc ScFv antibody heavy chain vary region, mRNA for ScFv collagenase heavy chain vary region, AE0199 immunoglobulin heavy chain,mouse Ig gamma-chain,Ig rearranged gamma-chain mRNA,anti-NP antibody IgH,mRNA for arginine/serine kinase,dual specificity phosphatase,family mRNA telomerase-associated protein,anti-human erB-2 region,BMP-4 gene,etc; In test group of 4 d, higher similar sequences were as follows: mRNA for sodium channel,tazarotene-induced gene,betaine-GABA transporter gene,homobox protein Xgbx-2 mRNA,mRNA for stress-activated protein,FK506 binding protein,calium /calmodulin dependent gene,PEST phosphatase interactin gene,haptoglobin mRNA, etc;In test group of 8 d, higher similar sequences were as follows: Ig Mu variable region mRNA,Mus musculus Ig K chain mRNA V-region, mRNA for Hox1b protein,Mus musculus neutroactin mRNA, rat alkaline phosphatase mRNA,Human mRNA for XP-C repair complementing protein,human alpha-2-plasmin inhibitor gene,mRNA for CCAT binding factor,mouse active H-chain VJ region,etc. Eighteen were new sequences,whose function were unclear. Ninety clones were obtained to be associated with repair of damaged mice intestinal gland cells caused by γ ray and treated by small intestinal RNA.Repair of damaged intestinal gland cells treated by exogenous nucleic acids may be associated with hsp,Nmi,Dutt1,alkaline phosphatase genes and eighteen new sequences.

Abstract:The content of GABA, glycine and taurine in cortex, cerebellum and basilar nucleus of hamster living in the magnetic free field space was determined in different time. The change of three neurotransmitters is not distinct with the lapse of time in cortex. The GABA was decreased gradually in cerebellum and basilar nucleus and the taurine was increaced in cerebellum after a month. This change is similar with that of corresponding area in the brain of some kinds of neuropathes.

Abstract:Notch proteins are involved in cell-fate selection throughout development. Signalling through the transmembrane receptor Notch is triggered by ligand binding, which induces the proteolytic cleavage of the Notch protein. This cleavage generates an intracellular fragment of the Notch protein (Notch-ICD), which translocates into the nucleus and modifies transcription of target genes through its association with the CSL familily of DNA binding protein (where CSL stands for CBF1, Su (H), Lag-1). Notch activity affects the implementation of differentiation, proliferation, and apoptotic programs, providing a general developmental tool to influence organ formation and morphogenesis. To obtain recombinant rat NICD, a long template and high fidelity PCR was used to clone NICD (1744V-2530K) DNA fragment from rat brain cDNA library. The cloned NICD fragment was confirmed by sequencing and then subcloned into glutathione -S-transferase (GST) fusion protein expression vector pGEX-KG. The GST-NICD fusion proteins were expressed in E.coli JM109 after inducing by IPTG. The fusion proteins were purified by affinity chromatography on glutathione Sepharose 4B.

Abstract:The phagocytosis to Staphylococcus aureus (SA) and cultivated U937 cells by macrophages derived from PBMC was enhanced significantly under lipopolysaccharide(LPS) stimulation. The present experiment showed that the application polyclone antibodies to TLR2 suppressed partly the phagocytosis of macrophages in this model. The LPS-enhanced phagocytosis could be further blocked partly by polyclone antibodies to TRAIL or TNFα. Cells cultivated in a lower serum concentration(1%) was also shown to be a decreased phagocytosis. The results confirmed that TLR2 was a LPS receptor which mediated its signal transduction, while some serum factors participated in the binding of LPS to its membrane receptors. It further suggested that LPS induced effectors such as TRAIL and TNFα might be the key mediators involved in the mechanisms of LPS-enhanced phagocytosis.

Abstract:Superoxide radicals(O₂^-_·) produced in PSⅡ particles separated from spinach has been investigated by spin trapping-electron spin resonance (ESR) technique. After bubbling with oxygen and incubating with tetracyanoethylene (TCNE) that acts as an inhibitor of superoxide dismutase (SOD) the experimental evidence of spin adduct of ［DMPO-O₂H］^· can be obtained by in situ ESR measurements in PSⅡ particles. In contrast, adduct of O₂^-_· and DMPO produced under illumination is obviously decreased when SOD that usually performs as a scavenger of O₂^-_· is present. Furthermore, it is evident to find that the generation of O₂^-_· is positively correlated with the concentration of oxygen. The production of O₂^-_· is also pH dependent, and O₂^-_· concentration reaches maximum when pH is in the range of 6.0～6.5. Either high, or low pH value will lead it to descend steeply.In Tris-HCl washed PSⅡ particles donor-side ET inhibition can causes the production of O₂^-_· decreasing obviously. It can be concluded that the PSⅡ that is active in splitting water and oxygen generation is also a reactive site responsible for the photoinduced O₂^-_· generation in thylakoid of higher plant. In another word, the formation of O₂^-_· is relevantly correlated to the electron transport activity of PSⅡ.

Abstract:The chemotactic peptide fMLP was known to induce adhesion, migration and phagocytosis of neutrophil. To clear the mechanism of the chemotaxis, the effects of PI3-K, p38 and ERK on actin polymerization were studied with the inhibitors of these kinases in neutrophil-like, differentiated HL-60 cells stimulated with fMLP. 0.1 μmol/L Wortmannin (PI3-kinase inhibitor) inhibited the fMLP-induced polymerization of actin. 50 μmol/L SB203580 (p38 inhibitor) and 50 μmol/L PD98059 (ERK inhibitor) did not inhibited it, though p38 and ERK were regulated by PI3-K. These results suggest the signaling pathway of actin polymerization mediated by PI3-K was different from that of p38 and ERK activation mediated by PI3-K.

Abstract:La-chlorophyll-a, Sm-chlorophyll-a and Cu-chlorophyll-a were synthesized from pheophytin-a, lanthanum, samarium and cuprum in the acetone solution. Their characteristics have been investigated by ultravioler-visible (UV-Vis), FT-IR and extended X-ray absorption fine structure spectra (EXAFS). The Soret band of UV-Vis spectra of La-chlorophyll-a, Sm-chlorophyll-a and Cu-chlorophyll-a was more ultraviolet shift than that of pheophytin-a, the Q band was more red shift than that of pheophytin-a. FT-IR spectra of La-chlorophyll-a, Sm-chlorophyll-a and Cu-chlorophyll-a was similar with chlorophyll, but different from pheophytin. UV-Vis and IR spectra confirmed the coordination of La(Ⅲ), Sm(Ⅲ) and Cu(Ⅱ) to the porphyrin rings. By extended X-ray absorption fine structure spectra method, it was found that the molecular structure of synthesized La- Chlorophyll-a, Sm-chlorophyll-a could be well fitted by the double decker sandwich structure model that La, Sm was surrounded by eight nitrogen atoms from two porphyrin rings. It is believed that chemical form of La-chlorophyll-a, Sm-chlorophyll-a was a sandwich structured complexes with the La-N and Sm-N bond length of average 0.261 nm and 0.243nm, respectively. Extended X-ray absorption fine structure spectra showed that Cu-chlorophyll-a could be well fitted by the mono decker structure model that Cu was surrounded by four nitrogen atoms from porphyrin rings, Cu-N bond length of average was 0.197 nm. Elemental analysis indicated that La-chlorophyll-a and Sm-chlorophyll-a have the double decker sandwich structure, Cu-chlorophyll-a has the mono decker structure.

Abstract:By the use of the applied research cation measurement system, Fura-2 fluorescence measurement method was forwarded to detect the intracellular La³⁺ concentration, and used for investigating the transmembrane behaviors of La³⁺ to PC12 cells. An apparent dissociation constant of La³⁺-Fura-2 was 3.27×10^-11 mol·L^-1 in solutions simulating intracellular ionic composition, with pH 7.05. La³⁺ could not enter PC12 cell under the normal condition, and also could not enter the cell via the calcium channel stimulated by KCl and norpinephrine. However La³⁺ entered PC12 cell after Na⁺ within the cell were overloaded using ouabain. Amount of La³⁺ entering PC12 cell were related to both outer cellular La³⁺ concentration and intracellular overloaded Na⁺ concentration. It is suggested that La³⁺ enter the cell in Na⁺/La³⁺ exchanging mechanism.

Abstract:Hepatitis C virus(HCV) encoded non-structure protein 5B(NS5B) is believed to be a RNA dependent RNA polymerase. GST-NS5B fusion protein was expressed and purified and its ability to bind to the 1～585 nucleotides of 3′-terminal negative-strand RNA sequences was examined by UV cross-linking. Results presented here demonstrated that the NS5B binding to this region increased with the dosage of protein. The binding ability of NS5B to 3′-terminal negative-strand RNA sequences was approximately 10 folds higher than to 3′ UTR X region of positive-strand RNA. The specificity of NS5B binding to 3′-terminal negative-strand RNA sequences was tested by competition with unlabelled RNA probe or an unrelated RNA/proteins. Results showed that the excess amount of cold probe RNA was able to almost completely compete out the complex resulted from protein-RNA interaction. However unrelated RNA and protein were demonstrated no competition with NS5B. These results suggest that NS5B is a participating component of 3′-terminal replica of HCV negative-strand RNA.

Abstract:Inteins are internal segment peptides which can self-splicing at the protein level. Although inteins are found in all three domains of life, they are not evenly distributed among species and proteins. So the evolution of intein have been capturing much attention. 69 classical inteins were found through systematically searching nucleic acids database. The comparison of homologous protein and phyogenetic tree of inteins suggest that the evolution of inteins should combine two causes: lateral transmission and inheritance.

Abstract:In order to study the structure specificity of HPV16 E6 gene of a Chinese Uygur patient of cervical carcinoma in south Xinjiang, the tissue DNA was extracted from cervical carcinoma biopsies. HPV16E6 gene was amplified by PCR from the cervical carcinoma tissue DNA. The HPV16 E6 gene was cloned into pUCm-T and analyzed the whole sequence. The result of PCR showed that the positive rate of HPV16 E6 was 82.35%(14/17). The result of sequence showed that the overall length of strain is 456 bp, it was the same as the German strain. The 247th nucleotide of HPV16 E6 mutate T to G, the mutation had changed the triplet codes, subsequently changed the amino acids coded. There is a structure difference between HPV16 E6 gene of Xinjiang strain and the standard strain.

Abstract:MT and αα genes were introduced into Petunia by Agrobacterium-mediated transformation. Transformants, especially the ones transformed by αα gene, displayed the obviously higher resistance and accumulation of Pb than control plants. The growth of the roots and shoots of plants transformed by MT and αα genes was unaffected by up to 150 μmol/L Pb and 200 μmol/L Pb, respectively; whereas control seedlings showed severe inhibition of roots’ and shoots’ growth and leaves’ wither under 100 μmol/L Pb. After the transformants were selfed, the seedlings of offspring from MT and αα positive plants were tested for resistance to Pb. It was found that the transformants could tolerate higher concentration of Pb. The detection of accumulation of Pb in the transformed plants by MT and αα genes showed 28% and 35% more than non-transformants, respectively. The results of these experiments indicated that the ornamental plant:Petunia could be used for treatment of the toxic heavy metal Pb pollution in soil.

Abstract:Autoradiograph assay of p38 MAPK (mitogen-activated protein kinase) activity was established, and applied in measurement of p38 MAPK activity of vascular endothelial cell stimulated by lipopolysaccharide (LPS). Results showed that autoradiograph assay possessed specificity and sensitivity. Activity of p38 MAPK in endothelial cell treated by LPS was increased at 15 min, and reached maximum value during 30～60 min,then descended. It suggested that domestic laboratory completely had the ability to establish autoradiograph assay of kinase activity,and applied in study of signal transduction.

Abstract:A three-step sequential protein extraction method was applied in proteomics analysis: using three kinds of solutions with differential solubility to replace one kind of solution. The method increases the efficiency of extraction and separation of the proteins compared with method of one solution.

Abstract:The Blast program developed by National Center for Biotechnology Information (NCBI) is one of the powerful tools for sequence analysis including both nucleotide and amino acid sequences. Although it could be used for multiple sequences alignment, the result is not always available. After analysis of the blast result, a new algorithm was designed to optimize the multiple alignment of Blast. A program named "Mblast" was then developed for application. Result demonstrated that the program is useful in identifying conserved region of multiple sequences.

Abstract:To find practical and simple transformation methods in transgenic silkworm research, the sperm-mediated methods were tried. The constructed plasmid pFbGFP was transformed into silkworm(Bombyx mori) with three different sperm-mediated transformation methods. Positive results of PCR and Southern blotting was screened in the following two generations. 30% positive rate of the second generation was obtained by one of the methods. This result showed that this was an effective method for transformation of silkworm with foreign gene.

Abstract:To explore the biological functions of polyamines, the analytical method of polyamines by capillary electrophoresis with laser-induced fluorescence detector (LIF) was developed. After derivatization of polyamines with isothiocyanatefluorescin, using borate (pH 8.6) as running buffer, putrescine, spermine, spermidine and 1,6-diaminohexane were separated successfully within 8 min at the voltage of 20 kV. The linear range, stability, detection limit and recovery were examined, the method was simple, sensitive and rapid. The results of polyamines in serum showed: The levels of spermine and spermidine were significantly higher in rat serum of tumor than in rat serum of control group and non-tumor group. There was no markedly difference between the levels of spermine and spermidine in rat serum of control group and in rat serum of non-tumor group. The levels of putrescine in serum were no obviously difference between any groups.

Abstract:The interpretation of protein physical properties at the most fundamental mechanistic and thermodynamic level plays a key role in physical and molecular understanding of biology. The protein thermodynamic structure (potherse) is generated through irreversible thermodynamic possesses. Protein folding is a specific physical mechanism for the origin of natural order. It was shown that pothersal change is the basic (molecular) thermodynamic unit of any physiological reaction which acts as a molecular switch. The Weiss equation is re-derived using protein mechanics theory. Some protein physical properties are also discussed.