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Common Sequence (common + sequence)
Selected AbstractsThe large form of ADAR 1 is responsible for enhanced hepatitis delta virus RNA editing in interferon- , -stimulated host cellsJOURNAL OF VIRAL HEPATITIS, Issue 3 2006D. Hartwig Summary., Hepatitis delta virus (HDV) RNA editing controls the formation of hepatitis-delta-antigen-S and -L and therefore indirectly regulates HDV replication. Editing is thought to be catalysed by the adenosine deaminase acting on RNA1 (ADAR1) of which two different forms exist, interferon (IFN)- , -inducible ADAR1-L and constitutively expressed ADAR1-S. ADAR1-L is hypothesized to be a part of the innate cellular immune system, responsible for deaminating adenosines in viral dsRNAs. We examined the influence of both forms on HDV RNA editing in IFN- , -stimulated and unstimulated hepatoma cells. For gene silencing, an antisense oligodeoxyribonucleotide against a common sequence of both forms of ADAR1 and another one specific for ADAR1-L alone were used. IFN- , treatment of host cells led to approximately twofold increase of RNA editing compared with unstimulated controls. If ADAR1-L expression was inhibited, this substantial increase in editing could no longer be observed. In unstimulated cells, ADAR1-L suppression had only minor effects on editing. Inhibition of both forms of ADAR1 simultaneously led to a substantial decrease of edited RNA independently of IFN- , -stimulation. In conclusion, the two forms of ADAR1 are responsible almost alone for HDV editing. In unstimulated cells, ADAR1-S is the main editing activity. The increase of edited RNA under IFN- , -stimulation is because of induction of ADAR1-L, showing for the first time that this IFN-inducible protein is involved in the base modification of replicating HDV RNA. Thus, induction of ADAR1-L may at least partially cause the antiviral effect of IFN- , in natural immune response to HDV as well as in case of therapeutic administration of IFN. [source] TERE; a novel cis -element responsible for a coordinated expression of genes related to programmed cell death and secondary wall formation during differentiation of tracheary elementsTHE PLANT JOURNAL, Issue 6 2007Hyunjin Pyo Summary The differentiation of water-conducting tracheary elements (TEs) is the result of the orchestrated construction of secondary wall structure, including lignification, and programmed cell death (PCD), including cellular autolysis. To understand the orchestrated regulation of differentiation of TEs, we investigated the regulatory mechanism of gene expression directing TE differentiation. Detailed loss-of-function and gain-of-function analyses of the ZCP4 (Zinniacysteine protease 4) promoter, which confers TE-specific expression, demonstrated that a novel 11-bp cis -element is necessary and sufficient for the immature TE-specific promoter activity. The 11-bp cis -element-like sequences were found in promoters of many Arabidopsis TE differentiation-related genes. A gain-of-function analysis with similar putative cis -elements from secondary wall formation or modification-related genes as well as PCD-related genes indicated that the cis -elements are also sufficient for TE-specific expression of genes. These results demonstrate that a common sequence, designated as the tracheary-element-regulating cis -element, confers TE-specific expression to both genes related to secondary wall formation or modification and PCD. [source] Primary tooth emergence in Australian children: timing, sequence and patterns of asymmetryAUSTRALIAN DENTAL JOURNAL, Issue 3 2010S Woodroffe Abstract Background:, Information on the timing and sequence of human tooth emergence is valuable when analysing human growth and development, predicting the age of individuals, and for understanding the effects of genetic and environmental influences on growth processes. This paper provides updated data on the timing and sequence of primary tooth emergence in Australian children for both clinicians and researchers. Methods:, Twins were recruited from around Australia with data collected through parental recording of twins' primary tooth emergence. One twin from each pair was then randomly selected to enable the calculation of descriptive statistics for timing, sequence and asymmetry in tooth emergence. Results:, The first and last primary teeth emerged, on average, at 8.6 months and 27.9 months, respectively, with teeth emerging in the order: central incisor, lateral incisor, first molar, canine, second molar. Left-side antimeric teeth were more likely to emerge before their right-side counterparts but this was not statistically significant. At least 35% of all antimeric pairs had emerged within two weeks of each other, serving as a useful guideline for assessing symmetrical versus asymmetrical development. Conclusions:, Primary tooth emergence in Australian twins is occurring later than reported previously for Australian singletons but is consistent with findings for singletons in other ethnic groups. The most common sequence of primary tooth emergence appears to be consistent in twins and singletons and has not changed over time. [source] A refined technique for determining the respiratory gas exchange responses to anaerobic metabolism during progressive exercise , repeatability in a group of healthy menCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2004Anita G. M. Wisén Summary The respiratory gas exchange and ventilation during an incremental cycle exercise test were analysed in a group of 19 healthy, moderately fit men. Different computer algorithms were used to estimate the V,O2 values where: (i) the rate of V,CO2 increase just exceeds the rate of V,O2 increase (DX, derivative crossing), (ii) V,CO2/V,O2 = 1·00 (PX, point of crossing) and (iii) ventilation (V,E) increases disproportionately in relation to V,CO2 (PQ, point of V,CO2 equivalent rise). The DX and PQ measurements were analysed using a new approach employing polynomial regression and the value of PX was determined following low-pass filtration of raw data. The repeatability of the measurements was evaluated with a 5,6 week interval between the tests. The correlations between tests were 0·75 at DX, 0·85 at PX and 0·62 at PQ. The mean differences between the repeated tests were not statistically significant. The repeatability of V,O2, in absolute values expressed as ±2 SD of the differences between the tests, had values of 5·0, 6·1 and 9·5 ml min,1 kg,1 for DX, PX and PQ, respectively. The mean value of V,O2 for each measurement point expressed as a percentage of V,O2max was 54% at DX, 68% at PX and 70% at PQ. The most common sequence of the measured values was DX < PX < PQ, but the sequence DX < PQ < PX was also observed. It is concluded that the gas exchange responses to developing anaerobic metabolism during progressive exercise can be characterized by a series of thresholds. However, the considerable variation in absolute values in the two testing occasions requires further attention. [source] Plasmodium falciparum: binding studies of peptide derived from the sporozoite surface protein 2 to Hep G2 cellsCHEMICAL BIOLOGY & DRUG DESIGN, Issue 4 2001R. López Abstract:Plasmodium falciparum sporozoite surface protein 2 (Pf SSP2), also called thrombospondin related anonymous protein (TRAP), is involved in the process of sporozoite invasion of hepatocytes. Pf SSP2/TRAP possesses two different adhesion domains sharing sequences and structural homology with von Willebrand factor A-domains and human repeat I thrombospondin (TSP). Pf SSP2/TRAP has also been implicated in sporozoite mobility and in mosquito salivary gland invasion processes. We tested 15-mer long synthetic peptides having five overlapping residues covering the complete protein Pf SSP2 sequence in binding assays to Hep G2 cells. In these 57 peptides, 21 high-activity binding peptides (HABPs) were identified; five were in the adhesion domains already described and 16 were in two regions toward the protein's carboxy and middle terminal part. Six HABPs showed conserved amino acid sequences: 3243 (21FLVNGRDVQNNIVDE35), 3279 (201FLVGCHPSDGKCNLY215), 3287 (241TASCGVWDEWSPCSV255), 3289 (251SPCSVTCGKGTRSRK265), 3327 (441ERKQSDPQSQDNNGNY455) and 3329 (451DNNGNRHVPNSEDREY465). The HABPs show saturable binding and dissociation constants between 140 and 900 nm with 40,000,855 000 binding sites per cell. The 3279 (201FLVGCHPSDGKCNLY215), 3323 (421NDKSDRYIPYSPLSP435) and 3331 (461SEDRETRPHGRNNENY475) HABPs have B epitopes in their sequences; these have previously been recognized by antibodies partially inhibiting hepatocyte invasion and development of the hepatic state. The 3287 (241TASCGVWDEWSPCSV255) and 3289 (251SPCSVTCGKGTRSRK265) HABPs share common sequences with the Pf SSP2/TRAP region II plus, which is present in a great number of adhesion proteins. Based on this information, six new peptides covering the high binding regions identified previously were synthesized and, using a competition assay, the amino acid involved in the binding were determined. [source] | |||||||||||||