Abstract:Raf-1 protein kinase has been known as an important component of Ras/Raf-1/MAPK signaling pathway related to cell proliferation. It also may be a cross-talk point among different signal transduction pathways. This is a review about the characteristics of Raf-1 molecule, its activation and relationship with other proteins.

Abstract:The characterizations of chloroplast expressing system were described, and research progressing was also summerized, then put forward some questions about foreign gene expression in chloroplast, and give some ideas to resolve them.

Abstract:Cardiotrophin-1 is a novel member of the interleukin-6 cytokine family. Mouse CT-1 mRNA is about 1.4 kb in length, and the encoded protein contains a 203-aa open reading frame. It utilizes gp130 and LIFR as the signal transducing receptor components. As a multifunctional cytokine, it induces cardiac myocyte hypertrophy and promote cardiac myocyte survival. It can induce a phenotypic switch in rat sympathetic neurons and promote the survival of dopaminergic neurons, ciliary neurons and motoneurons. It can also inhibit the growth of the mouse myeloid leukemia cell M1, and induce liver acute phase response. The chronic administration of CT-1 to mouse increases platelet counts, red blood cell counts and haemoglobin concentration.

Abstract:Obesity is the disorder of the mechanisms in balancing food intake and energy expenditure. It leads to several diseases such as type Ⅱ diabetes,hypertension,hyperlipidaemia and cancers. The positional cloning of the obese gene provides an important approach to the research of the mechanisms of obesity. Leptin,the product of obese gene,acts on the hypothalamus, controlling metabolism, energy expenditure and reproductive system. Research data showed that the recombinant leptin normalized the metabolism and body weight of the obese gene defficiency mice and the neuropeptide Y defficiency mice,corrected the sterility of the obese gene defficiency mice. Further researches on the mechanisms of the obese gene and development of the drugs according to different kinds of defficiency can make it possible to the treatment of obesity.

Abstract:Adenoviruses are efficient gene transfer vectors for variety of cell types in vivo. The first-generation recombinant adenoviruses that lack E1 sequences have shown tremendous promise in animal and human models of gene therapy. Having some limitations at aspect of efficacy and safety,the adenovirus vectors are being gradually improved to resolve these problems. The developments of construction of adenovirus vectors in increasing the efficacy and safety was described.

Abstract:Matrix association region (MAR) is the DNA sequences in eukaryotic genome which can specifically associate with the nuclear matrix. By means of specific interaction with some MAR-binding proteins, MAR plays important roles in eukaryotic gene's replication, expression and regulation, and chromosomal construction. MAR-binding proteins include some structural proteins in chromatin or nuclear matrix (such as histone H₁, topoisomerase Ⅰ & Ⅱ, HMG I/Y, lamin B₁, and matrins.) and some tissue-specifically expressed proteins, including SATB₁ (special AT-rich binding protein 1) and osteocalcin gene promoter-binding factors. By the relationship with the nuclear matrix, these MAR-binding proteins can be classified in three groups, nuclear matrix-abundant composition, rare composition and non-nuclear matrix composition. Their interactions with MARs were compared and analyzed as well.

Abstract:Insulin-like growth factor 1 is a multifunctional cell regulating factor. It has been demonstrated that structural characteristics of IGF1 provide clues for its growth promoting and anabolic effect. It is concentrated on the three dimensional structure of human IGF1, and the combining regions between IGF1 and relative receptors and binding proteins. It also shows the important role of disulfide bonds in the protein folding.

Abstract:The relation between trinucleotide-repeat and neurologic disease is paid close attention by many reseachens. The development of gene cloning of neurologic diseases which are related to trinucleotide-repeat is introduced. A fuller description is given on the possible pathogenesis of trinucleotide repeat expansion.

Abstract:The research on triple helix DNA developed very rapidly in the last ten years and has become an important field of both molecular biology and genetic engineering. The current progress in this field was reviewed according to its stability and biological function. the stability of triple helix was discussed in terms of its endogenous and exogenous conditions such as chain length, base sequence, base modification, backbone structure of ODN and temperature, pH, salt, ligand binding. At the same time, its biological functions were summarized. These functions include regulating genetic expression and transcription, protecting the DNA sequence from enzymes cleavage, serving as a molecular cleaver.

Abstract:Cl^－ channels are found in all of cellular and subcellular membranes which have been determined. As housekeeper, they play vital roles in many different processes, such as regulation of cell volume, pH, resting membrane potential and excitability. Because the classical electrophysiological investigation has not been able to clearly charactarize a macroscopic Cl^－ current, as was done for Na^＋，K^＋ and Ca²⁺ current, Cl^－ channel are ignored for many years. The recent explosion in knowledge of Cl^－ channel is owing the technical using of single channel recording and molecular biology. The ionic permeation, selectivity, gating and pharmacological properties as well as the molecular clone and structure of background Cl^－ channels, the most widely existed Cl^－ channel in biomembranes, are reviewed.

Abstract:Proteinase inhibitors are widely distributed in the plant kingdom and associated with the resistance of plant against insects and pathogens. Ingestion of some plant proteinase inhibitors in the artificial diet can retard the growth and development of insects, even cause the insects dead. Transgenic plants of proteinase inhibitors derived from plants definitely show effects of insect-resistance. Insects can reduce the growth and development inhibition by secreting gut proteinases that insensitive to plant proteinase inhibitors existed in the diet. The quantity and quality of food proteins are very important in dictating the anti-nutritional effects of plant proteinase inhibitors on insects. Plant proteinase inhibitors can be induced by the infection of many plant pathogens, and the growth of microorganism isolated from the spoiled tissues can be inhibited by the induced plant proteinase inhibitors. Progress in the roles of plant proteinase inhibitors in the resistant mechanism of plant against insects and pathogens was reviewed.

Abstract:Multicolor fluorescence in situ hybridization, a new promising molecular cytogenetic technique, permits the simultaneous detection several specific nucleic acid sequences in interphase as well as metaphase by using cohybridization of probes labeled with serveral fluorescent labels or label combinations. It provids a simple, fast, and reliable means to assess genetic instability in cancer. This approach is being applied generally in physical mapping,mutation research, tumor pathology and prenatal dignosis.

Abstract:A new continuous flow electrophoresis system was fabricated. The principle, the composition and the structure of the prototype were discussed.

Abstract:Two types of protein mixture of hemoglobin and cytochrome c were separated successfully with continuous flow electrophoresis.The result that separated samples were inspect using UV and PAGE relates to many parameters such as gap of separation chamber, flowing velocity of sample, flowing volocity of buffer, pH, conductance and power.

Abstract:To study further the role of Ca²⁺ and protein kinase C in platelet aggregation, suspensions of aspirin-treated, ³²P-prelabled, washed pig platelets containing ADP scavenger in the buffer were stimulated by Ca²⁺ ionophore A23187 and PMA,a stimulator of protein kinase C. The results indicated that: (1) 1～20 μmol/L A23187 induced platelet aggregation,as well as the phosphorylation of 40 ku and 20 ku proteins.There were dose-respone and time-respone effects of the protein phosphorylation in A23187-induced platelet activation. (2) A23187 and PMA were synergistic in platelet aggregation and protein phosphorylation. (3)Stauroporine, a protein kinase C inhibitor, in concentration of 1 μmol/L,largely suppressed platelet aggregation and completely suppressed phosphorylation of 40 ku and 20 ku proteins induced by 20 μmol/L A23187. The results imply that Ca²⁺ mobilization alone could activate protein kinase C in platelet, and Ca²⁺-induced platelet aggregation is largely dependent on activation of protein kinase C.

Abstract:The first intron sequence of human α1(Ⅰ) collagen (COLⅠA1) gene has been shown to have differential activities of transcription regulation in a variety of tissue cells. To determine the activity of the first intron of COLⅠA1 gene and then utilize the regulatory elements to perform ectopic expression of foreign genes in human fibroblasts. Two novel recombinants pSCEP-CAT and pSCIP-CAT were constructed in which the intronic +544～+855 and +820～+1 093 segment of COLⅠA1 gene were cloned respectively in the upstream position of the promoter sequence of this gene followed by chloramphenical acetyltransferases (CAT) gene. Human fetal tendon fibroblasts and Tca 8113 tongue cancer cells in culture were transfected with the recombinants by using LipofectAMINE^TM, and then tested the expression level of CAT gene with DIG-labeled anti-CAT ELISA. The results indicate that the first intronic +544～+855 segment of COLⅠA1 gene has an enhancing effect on the expression of CAT gene driven by the promoter in the tranfected human fetal tendon fibroblasts and Tca 8113 tongue cancer cells. Interestingly, the first intronic +820～+1 093 segment has strongly stimulating effect on the expression of the marker gene in the tongue cancer cells, but inhibitory effect in the fibroblasts.

Abstract:A new method for the representation of smooth molecular surface was proposed. The embracing surface, which started from a triangular mesh built on an ellipsoid embracing the whole molecular surface, is deflated stepwise until all the triangles will stick the surface of the molecule. This method can be easily used to get the cavity of the protein.

Abstract:A modified method for seperating neutrophils from whole blood was reported. Neutrophils was obtained by dextran sedimentation, centrifuged with lymphocytes separating solution, special seperting medium washing and erythrocyte depletion. The purity and viability were proved to be both about 95% by Wright's stain and Typan blue respectively. Both the chemiluminescence method and cytochrom c reduction method proved the high activity and the integrity of the membrane receptor of the neutrophils. Compared with other method, this method is more simple and easier to handle, which suggests that it is a efficient and economic method for seperating neutrophils.

Abstract:Content of DNA, rasp21 and p53 in 80 case gastric precancer lesion was quantitative detected by flow cytometry and immunofluorescence techniques. and to investigate its in clinical value as early carceration marker.The detected results showed that raising in DNA heteroploid rate. Rasp21 and p53 protein expression were found with raising of dysplasia grade in gastric precancer lesion. The rate of canceration of gastric precancer lesionin in DNA heteroploid and rasp21 expression positive were notable increased. DNA heteroploid and rasp21 protein over-expression can be an early canceration molecular marker.

Abstract:Exon Trapping is a powerful method developed recently for isolating transcribed sequences from genomic DNA. Two novel exons, A91 and D12, were isolated from YAC209G4 spanning FRAXA site using the exon trapping system with pSPL3 as splicing vector. A91 was amplified strongly in fetal liver and skeletal muscle cDNA library and mildly in liver, kidney and bone marrow library, respectively. While D12 was failed to be detected from the 8 libraries. A fragment of 315 bp containing A91 has been cloned (AM4470) from the skeletal muscle cDNA library. A single transcript of 2.8 kb was detected from mRNA samples of human heart and skeletal muscle on multiple tissues Northern blot using AM4470 probe.

Abstract:An improved method was utilized for constructing hybrid arrested λ phage cDNA library by subtractive hybridization, in which magnetic particles were applied to separate monomers from hybrids, and candidate sscDNAs were enriched by subtracting two control mRNAs from one treated sscDNA. The results showed that this new approach had a efficient improvement in constructing cDNA library which increased the yield of monomers, simplified experimental procedures and enriched more candidate genes.

Abstract:Human CD14 gene was cloned from genomic DNA of PMA-stimulated HL-60 cells by PCR. Sequencing result showed that it is identical to the reported human CD14 gene except four bases, among which two new mutations were identified.

Abstract:The guanidinium thiocyanate-LiCl-hot phenol method for high purity and high integrity RNA isolation from plant tissues was established. Comparing with other methods that involved guanidinium thiocyanate, this method costs less and produces RNA molecules with better quality. The working concentration of guanidinium thiocyanate used was reduced more than 40 times compared with previous methods. The isolated RNA with this method gave 4 ribosomal RNA (rRNA) bands when analysed by formaldehyde agarose gel electrophoresis. Northern hybridization, mRNA isolation and following in vitro translation experiments performed with this RNA also gave good results.