Relationships of mRNA-protein secondary structures in the human β-globin gene HBB and four variants

Single nucleotide polymorphism is an interesting problem that can alter gene expression,recode amino acids and affect protein function.Protein structural changes have generally been attributed to amino acid replacements,and only a few research efforts have examined the effects of mRNA structural changes to the conformation of the corresponding protein coded by the mRNA.In the present study,the human β-globin HBB gene and four variants were examined.The mRNA secondary structures were constructed using the dynamic extended folding method and the encoded protein secondary structures were obtained from related databases.Comparisons were performed between these structures before and after mutations were introduced into the mature mRNAs and the proteins.We focused on the structural changes from mRNA to protein and found that regular protein conformations tend to match stable mRNA regions,whereas irregular protein conformations,such as β/γ turns and random coils,often match unstable mRNA regions.Mutations within unstable regions can alter the mRNA secondary structure and leave footprints in the protein structure.Comparison of the mRNA-protein secondary structure relationships represents a potential strategy to explore protein functional changes.     

Interactions of pyrogallol red with proteins and the determination of proteins by resonance light-scattering

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Non-viral gene delivery carrier of probe type host molecule ——Interactions between DNA and β-cyclodextrin derivative complexes (I)

GENE THERAPY IS A COMMON PROCESS TO DELIVER EXTRIN- SIC GENES INTO TARGET CELLS FOR FURTHER GENE EXPRESSION, FOR THE PURPOSE OF TREATING DISEASES. A WELL DESIGNED GENE DELIVERY CARRIER CAN EFFICIENTLY PACKAGE AND PRO- TECT NUCLEIC ACID FROM BEING DIGESTED BY A VARIETY OF ENZYMES IN VIVO AND SHOULD BE ABLE TO SPECIFICALLY LO- CATE EXTRINSIC GENES INTO THE TARGET ORGANISMS. S…     

Effects of point mutation C→T at - 64 of human δ globin gene promoter on DNA binding proteins

By electrophoretic mobility shift assay (EMSA), the effect of point mutation C→T at - 64 of human δ-globin gene on its binding proteins has been studied. Two segments of 36 bp from - 83- - 48 bp of the 6 globin gene promoter, named WOG and MOG, were synthesized. WOG includes wild type CAAT-like box (CCAAC), while MOG includes the mutant CAAT-like box (CCAAT, -64 C→T). Results indicate that: ( i ) in erythroid cell lines MEL, K562 and Hemin induced K562, the affinity of MOG with CCAAT binding protein (CBF) and GATA-1 was greatly increased; ( ii ) in Hemin induced K562 cell line, there were another two novel specific DNA binding proteins, named C and D temporarily, besides the above two factors. The former was combined with WOG and MOG, likely indicating its relation with the increased gene expression after induction. The latter was only combined with MOG, which had possible relationship with the point mutation of - 64 C→T; ( iii ) EMSA also indicates that the suppression mechanisms of the expression of 6 globin gene is different in various periods of human developments. The result evidently supports the hypothesis that the defect CAAT-like box in human 6 globin gene contributes the main reason of its low level expression. The defect c/s-acting element CAAT-like box affects gene expression by its combination with the frans-acting element CBF and GATA-1.     

Comparison of the Teaching Concepts between Chinese and Americans

This paper makes a comparative study on higher education in respect of four aspects in educational system between China and America,in the hope of finding reasons that can be useful to our cultivation in China.     

Comparative study on the effect of integrin αvβ3 on secretion of matrix metalloproteinases in human normal and carcinoma trophoblasts

The invasion of cytotrophoblast cells into the maternal endometrium during embryonic implantation is very similar to the metastasis of carcinoma cells. However, the significant difference is that the former is a highly controlled process. In this report, the effects of integrin αvβ3 on the secretion of matrix metalloproteinase (MMP) were compared between normal cytotrophoblast cells and choriocarcinoma cells by RT-PCR, gelatin zymography and immunocytochemistry. The results reveal that both normal cytotrophoblast cells and choriocarcinoma cells can express integrin αvβ3. The secretion of MMPs in normal cytotrophoblast cells is up-regulated by anti-αvβ3 antibody, whereas, decreased in choriocarcinoma cells. It was suggested that αvβ3 can modulate the expression of MMPs in trophoblasts, and this action is carried out through distinct mechanisms in normal and carcinoma cytotrophoblast cells.     

Identification of the Angel-related elements in cyprinid fishes and their phylogenetic implications

Angel-related element belongs to the family of miniature inverted-repeat transposable elements (MITEs). In this paper we report the identification of an Angel-related element in the series Leuciscini of cyprinid fishes, which is located in the second intron of the growth hormone (GH) gene. We have also found that this element is absent in orthologous locus in the series Barbini of cyprinid fishes, that provides new evidence for the monophyly of the series Leuciscini. The insertion of Angel-related element into the GH gene might take place in the common ancestor of the series Leuciscini after its divergence from the series Barbini. The high sequence divergence and relatively broad species distribution of Angel-related elements implies that they might be ancient transposons which appeared about 26 million years ago.     

Polycistronic strategy for cyanobacterial expression vector construction: Co-transcription of a human gene and a selective marker gene

A polycistronic expression vector, pKGA-NTF1, was constructed for the cyanobacterium. Within this vector, the spectinomycin/streptomycin resistance gene (aadA) facilitated the selection of transformants when co-transcribed with favorite genes. A natural glnA gene was selected as the platform to introduce the plasmid into a neutral site of the Synechococcus sp. PCC 7002 chromosome. Function of the vector was demonstrated by the insertion of a modified human Trefoil factor 3 gene (NTF1) to upstream of the aadA gene and by the analyses of the transformed strains. Antibiotics resistance assays showed that the dicistronic expression cassette conferred high spectinomycin resistance to both the E. coli cells and the Synechococcus cells. PCR analysis and Western-blot analysis were carried out to confirm the integration and expression of the NTF1 gene, respectively. Through simple molecular manipulations, the artificial polycistronic structure described here can be conveniently used to express other favorable genes or operons in cyanobacteria, and to study the cyanobacterial gene expression as well.     

Calculation of baffle effect and mutual interaction between elements for an underwater acoustic conformal array with application to the optimization of projecting beampattern

The boundary element theory together with the optimization method is used to calculate the driving voltage weighting vector of a conformal array of underwater acoustic projecting transducers to obtain a low-sidelobe beampattern. At first, the relationship between the acoustic radiated field and the vibra- tion velocity of the array is formulated from the boundary element equation when the boundary im- pedance of the array baffle is specified. Then, the mutual impedance matrix of the array is calculated, and the relationship between the driving voltage and the vibration velocity of the transducers is pre- sented based on the equivalent circuit principle. At last, the driving voltage weighting vector of the array is calculated through an optimization method to obtain a low-sidelobe projecting beampattern. Computer simulation is conducted for a 14-element conformal array. An experiment has been carried out to measure the radiation directivity of the array in an anechoic water tank. The calculated and the experimental results show that the proposed method accounts for the acoustic effect of the baffle and the mutual interactions among transducers successfully and obtain a low-sidelobe projecting beam- pattern, and at the same time provide the largest amplitude of pressure in the axial direction when the maximum amplitude of the driving voltage weighting vectors keeps unchanged.     

Relation between human existence and environment viewing from the distribution of prehistoric archaeological sites in the Three Gorges reservoir region of the Yangtze River,China

Based on archaeological research findings in the Three Gorges region as well as the distribution of prehistoric sites in this area,the following conclusion can be derived:the unique physical and geographical conditions and variations in the Three Gorges region make local people of different ages seek their survival and development in the favorable environment along the riverbanks.Environment evolution has direct impact on the selection of location for survival.The increase of sites quantity reflects the favorable natural environment,but the decrease just reflects the consequence of such natural disasters as flood.     

The Comparison of the Etiquette between the Domestic and Foreign Hospital Culture

The etiquette is a complex behavioral science. It means thepractices and forms prescribed by social convention or by au-thority. During communication with other people, the personmust obey the some etiquette from beginning to end to governone' s own condu…     

Spectroscopic studies of the interaction between methylene blue and G-quadruplex

The telomere is a complex of simple guanine-rich repeating sequences of single-stranded DNA and pro-tein at the ends of eukaryotic chromosomes[1―3]. Hu-man telomere consists of the sequence, 5′-TTAGGG-3′, with the length ranging from 5 to 15 kb. The gu…     

Relationships between the Tensile Properties and Tenacity-extension Behaviour of Fibre-bundles

Fibre bundle testing is different from single-fibre measurement, not only in testing methods and instruments, but in the results obtained. For wool fibres, Sirolan-TENSOR can supply fibre-bundle tenacity (BS) and bundle extension ( BE), but has some limitations on the analysis of the measured tensile curves of fibre bundles. It has not only raised new parameters, such as initial modulus (BM) and specific work of rupture (BW), as well as the specific work before or after the peak-point(WBP or WAP) and the ratios of WAP/WBP and WAP/BW, but also compared the tensile behaviour of different fibre-bundles, e.g. wool, polyester and viscose rayon fibre-bundles. The experimental results from 32 lots of wool tops show that there are correlations between bundle tensile properties, such as BS-BE, BS-BM, BS-BW, BE-BW and BM-BW. However, the variables of coefficients of variance (CV) are almost independent of each other and have no correlation with the average values of fibre bundle tensile parameters, except for BS-     

Isolation of tomato proteinase inhibitor Ⅱ gene and the function of its intron

The genomic DNA sequence of tomato proteinase inhibitor Ⅱ gene (named tin2i, whose accession number in GenBank is AF007240) was isolated by PCR techniques. The intron sequence (TPI), with a length of 109 bp, owns typical structures of GT/AG dinucleotides at both ends and high content of AT base pairs which accounts for 80.7% of the total nucleotides. As shown by recombination experiment, the TPI sequence could efficiently promote the expression of the reporter gene gusA and this effect was independent of the position and orientation of the intron, thus showing its role as an enhancer. Such experiments as gel retardation assays, GUS histochemical staining and GUS fluorometric assays further demonstrated that TPI sequence maybe has promoter-like activity.