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991.
DNA序列的一种分类方法 总被引:1,自引:0,他引:1
刘志 《陕西师范大学学报(自然科学版)》2002,(Z1)
基于小波变换和相关技术,提出了一种DNA序列的分类方法.首先将DNA序列转换成数字序列,然后对此序列进行Matlab快速分解,计算未知类别序列与已知类别序列的相关系数,由此判定序列的类别.结果表明,该方法是切实可行的. 相似文献
992.
993.
994.
A simple and rapid method for isolation of high quality mitochondrial DNA (mtDNA) is presented in this report. Using this method, isolation and restriction site maps for 10 enzymes of the mtDNA ofDrosophila serrata were established. 相似文献
995.
996.
酶性DNA(Ⅵ)--应用重氮化联大茴香胺检测DNA的酯酶活性 总被引:1,自引:1,他引:0
应用自行合成的重氮化联大茴香胺检测萘酚,表明DNA能催化乙酸萘酯的水解,印证了以前关于DNA具有酯麦活性的实验结果DNA对重氮化联大茴香胺与萘酚的显色无增色效应,因而可以推论DNA在反应体系中确能促进萘酯水解而产生萘酚。 相似文献
997.
LIHui HANBaoshan 《科学通报(英文版)》2003,48(8):800-803
DNA is a kind of promising molecule as nano-lead to build or connect nano-devices due to its stable linear structure and certain conductivity. Many methods have been applied to constructing nano-patterns by using DNA molecule. In this report it is presented that λ-DNA was aligned on Si substrate by using the free-flowing method and then imaged by an atomic force microscope (AFM). After the second liquid flow, a catenary-like pattern and a crossed network of λ-DNA were formed. In addition, the aligned λ-DNA was successfully cut off by tips of AFM. 相似文献
998.
Microtubule associated protein tau binds to double-stranded but not single-stranded DNA 总被引:3,自引:0,他引:3
Hua Q He RQ Haque N Qu MH del Carmen Alonso A Grundke-Iqbal I Iqbal K 《Cellular and molecular life sciences : CMLS》2003,60(2):413-421
Tau, a major microtubule-associated protein of the neuron, which is known to promote the assembly of and to stabilize microtubules,
has also been seen associated with chromatin in neuronal cell lines, but its role in this subcellular compartment is still
unknown. In this study, the binding of tau to DNA was investigated using the electrophoretic mobility shift assay. Using polynucleotide
as probe, we found that tau bound to double-stranded but not to single-stranded DNA. Formation of tau-polynucleotide complex
was disrupted by alkaline pH and a high concentration of NaCl, but was not affected by dithiothreitol. Electron microscopy
revealed that the protein associated with the nucleic acid in a necklacelike manner. DNA-cellulose chromatography and radioimmunodot-blot
analyses showed that calf thymus histones VI-S, VII-S and VIII-S could replace both recombinant human brain tau352 (tau-23) and tau441 (tau-40) from DNA. Thus, tau appears to bind to DNA reversibly in the presence of histones.
Received 24 November 2002; received after revision 28 December 2002; accepted 30 December 2002
RID="*"
ID="*"Corresponding author. 相似文献
999.
Bandholtz L Guo Y Palmberg C Mattsson K Ohlsson B High A Shabanowitz J Hunt DF Jörnvall H Wigzell H Agerberth B Gudmundsson GH 《Cellular and molecular life sciences : CMLS》2003,60(2):422-429
CpG motifs originating from bacterial DNA (CpG DNA) can act as danger signals for the mammalian immune system. These CpG
DNA motifs like many other pathogen-associated molecular patterns are believed to be recognized by a member of the toll-like
receptor family, TLR-9. Here we show results suggesting that heat shock protein 90 (hsp90) is also implicated in the recognition
of CpG DNA. Hsp90 was characterized as a binder to oligodeoxynucleotides (ODNs) containing CpG motifs (CpG ODNs) after several
purification steps from crude protein extracts of peripheral blood mononuclear cells. This finding was further supported by
direct binding of CpG ODNs to commercially available human hsp90. Additionally, immunohistochemistry studies showed redistribution
of hsp90 upon CpG ODN uptake. Thus, we propose that hsp90 can act as a ligand transfer molecule and/or play a central role
in the signaling cascade induced by CpG DNA.
Received 18 December 2002; accepted 6 January 2002
RID="*"
ID="*"Corresponding author. B. Agerberth and G. H. Gudmundsson contributed equally to this work. 相似文献
1000.
LIUYuying WANGPengye DOUShuoxing XIEPing WANGWeichi YINHuawei 《科学通报(英文版)》2005,50(8):731-737
The effects of monovalent (Na^ , K^ ) and divalent (Mg^2 , Ca^2 , Mn^2 ) ions on the interaction between DNA and histone are studied using the molecular combing technique. λ-DNA molecules and DNA-histone complexes incubated with metal cations (Na^ , K^ , Mg^2 , Ca^2 , Mn^2 ) are stretched on hydrophobic surfaces, and directly observed by fluorescence microscopy. The results indicate that when these cations are added into the DNA solution, the fluorescence intensities of the stained DNA are reduced differently. The monovalent cations (Na^ , K^ ) inhibit binding of histone to DNA. The divalent cations (Mg^2 , Ca^2 , Mn^2 ) enhance significantly the binding of histone to DNA and the binding of the DNA-histone complex to the hydrophobic surface. Mn^2 also induces condensation and aggregation of the DNA- histone complex. 相似文献