共查询到20条相似文献，搜索用时 15 毫秒
1.
Design of DNA-binding peptides based on the leucine zipper motif 总被引：43，自引：0，他引：43
2.
Helix geometry, hydration, and G.A mismatch in a B-DNA decamer 总被引：35，自引：0，他引：35
G G Privé U Heinemann S Chandrasegaran L S Kan M L Kopka R E Dickerson 《Science (New York, N.Y.)》1987,238(4826):498-504
The DNA double helix is not a regular, featureless barberpole molecule. Different base sequences have their own special signature, in the way that they influence groove width, helical twist, bending, and mechanical rigidity or resistance to bending. These special features probably help other molecules such as repressors to read and recognize one base sequence in preference to another. Single crystal x-ray structure analysis is beginning to show us the various structures possible in the B-DNA family. The DNA decamer C-C-A-A-G-A-T-T-G-G appears to be a better model for mixed-sequence B-DNA than was the earlier C-G-C-G-A-A-T-T-C-G-C-G, which is more akin to regions of poly(dA).poly(dT). The G.A mismatch base pairs at the center of the decamer are in the anti-anti conformation about their bonds from base to sugar, in agreement with nuclear magnetic resonance evidence on this and other sequences, and in contrast to the anti-syn geometry reported for G.A pairs in C-G-C-G-A-A-T-T-A-G-C-G. The ordered spine of hydration seen earlier in the narrow-grooved dodecamer has its counterpart, in this wide-grooved decamer, in two strings of water molecules lining the walls of the minor groove, bridging from purine N3 or pyrimidine O2, to the following sugar O4'. The same strings of hydration are present in the phosphorothioate analog of G-C-G-C-G-C. Unlike the spine, which is broken up by the intrusion of amine groups at guanines, these water strings are found in general, mixed-sequence DNA because they can pass by unimpeded to either side of a guanine N2 amine. The spine and strings are perceived as two extremes of a general pattern of hydration of the minor groove, which probably is the dominant factor in making B-DNA the preferred form at high hydration. 相似文献
3.
The molecular structure of a DNA-triostin A complex 总被引：31，自引：0，他引：31
A H Wang G Ughetto G J Quigley T Hakoshima G A van der Marel J H van Boom A Rich 《Science (New York, N.Y.)》1984,225(4667):1115-1121
The molecular structure of triostin A, a cyclic octadepsipeptide antibiotic, has been solved complexed to a DNA double helical fragment with the sequence CGTACG (C, cytosine; G, guanine; T, thymine; A, adenine). The two planar quinoxaline rings of triostin A bis intercalate on the minor groove of the DNA double helix surrounding the CG base pairs at either end. The alanine residues form hydrogen bonds to the guanines. Base stacking in the DNA is perturbed, and the major binding interaction involves a large number of van der Waals contacts between the peptides and the nucleic acid. The adenine residues in the center are in the syn conformation and are paired to thymine through Hoogsteen base pairing. 相似文献
4.
Recognition of a DNA operator by the repressor of phage 434: a view at high resolution 总被引：66，自引：0，他引：66
A K Aggarwal D W Rodgers M Drottar M Ptashne S C Harrison 《Science (New York, N.Y.)》1988,242(4880):899-907
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Structure of the lambda complex at 2.5 A resolution: details of the repressor-operator interactions 总被引：73，自引：0，他引：73
The crystal structure of a complex containing the DNA-binding domain of lambda repressor and a lambda operator site was determined at 2.5 A resolution and refined to a crystallographic R factor of 24.2 percent. The complex is stabilized by an extensive network of hydrogen bonds between the protein and the sugar-phosphate backbone. Several side chains form hydrogen bonds with sites in the major groove, and hydrophobic contacts also contribute to the specificity of binding. The overall arrangement of the complex is quite similar to that predicted from earlier modeling studies, which fit the protein dimer against linear B-form DNA. However, the cocrystal structure reveals important side chain-side chain interactions that were not predicted from the modeling or from previous genetic and biochemical studies. 相似文献
7.
Synthesis of a sequence-specific DNA-cleaving peptide 总被引：19，自引：0，他引：19
J P Sluka S J Horvath M F Bruist M I Simon P B Dervan 《Science (New York, N.Y.)》1987,238(4830):1129-1132
A synthetic 52-residue peptide based on the sequence-specific DNA-binding domain of Hin recombinase (139-190) has been equipped with ethylenediaminetetraacetic acid (EDTA) at the amino terminus. In the presence of Fe(II), this synthetic EDTA-peptide cleaves DNA at Hin recombination sites. The cleavage data reveal that the amino terminus of Hin(139-190) is bound in the minor groove of DNA near the symmetry axis of Hin recombination sites. This work demonstrates the construction of a hybrid peptide combining two functional domains: sequence-specific DNA binding and DNA cleavage. 相似文献
8.
Zn-alpha2-glycoprotein (ZAG) is a soluble protein that is present in serum and other body fluids. ZAG stimulates lipid degradation in adipocytes and causes the extensive fat losses associated with some advanced cancers. The 2.8 angstrom crystal structure of ZAG resembles a class I major histocompatibility complex (MHC) heavy chain, but ZAG does not bind the class I light chain beta2-microglobulin. The ZAG structure includes a large groove analogous to class I MHC peptide binding grooves. Instead of a peptide, the ZAG groove contains a nonpeptidic compound that may be implicated in lipid catabolism under normal or pathological conditions. 相似文献
9.
Multiple global regulators control HIS4 transcription in yeast 总被引：63，自引：0，他引：63
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One- and two-dimensional nuclear magnetic resonance (NMR) methods were used to determine a three-dimensional model of an eight-base-pair DNA fragment (d-GGGTACCC) cross-linked with psoralen in solution. Two-dimensional nuclear Overhauser effect experiments were used to assign the spectrum and estimate distances for 171 proton pairs in the cross-linked DNA. The NMR-derived model shows a 53 degree bend into the major groove that occurs primarily at the site of drug addition and a 56 degree unwinding that spans the eight-base-pair duplex. 相似文献
12.
为了从拟南芥中获得抗灰霉病相关基因以及进行基因分析,本试验利用RACE技术获得了该基因的cD-NA全长(1190 bp),并用生物信息学方法和Southern Blotting技术明确了该基因是编码372个氨基酸的转录调节/结合蛋白的AT5G67480基因,以单拷贝形式存在于拟南芥基因组中。编码的蛋白含有BTB/POZ结构域,体外诱导表达的蛋白对灰霉病菌的生长有一定的抑制作用。 相似文献
13.
Structure and stability of X.G.C mismatches in the third strand of intramolecular triplexes 总被引：4，自引：0，他引：4
R F Macaya D E Gilbert S Malek J S Sinsheimer J Feigon 《Science (New York, N.Y.)》1991,254(5029):270-274
Intramolecular DNA triplexes that contain eight base triplets formed from the folding of a single DNA strand tolerate a single X.G.C mismatch in the third strand at acidic pH. The structure and relative stability of all four triplets that are possible involving a G.C Watson-Crick base pair were determined with one- and two-dimensional proton nuclear magnetic resonance techniques. Triplexes containing A.G.C, G.G.C, or T.G.C triplets were less stable than the corresponding parent molecule containing a C.G.C triplet. However, all mismatched bases formed specific hydrogen bonds in the major groove of the double helix. The relative effect of these mismatches on the stability of the triplex differs from the effect assayed (under different conditions) by two-dimensional gel electrophoresis and DNA cleavage with oligonucleotide EDTA.Fe(II). 相似文献
14.
Selective activation of transcription by a novel CCAAT binding factor 总被引：23，自引：0，他引：23
15.
Isolation and structure of a covalent cross-link adduct between mitomycin C and DNA 总被引：13，自引：0，他引：13
M Tomasz R Lipman D Chowdary J Pawlak G L Verdine K Nakanishi 《Science (New York, N.Y.)》1987,235(4793):1204-1208
A DNA cross-link adduct of the antitumor agent mitomycin C (MC) to DNA has been isolated and characterized; the results provide direct proof for bifunctional alkylation of DNA by MC. Exposure of MC to Micrococcus luteus DNA under reductive conditions and subsequent nuclease digestion yielded adducts formed between MC and deoxyguanosine residues. In addition to the two known monoadducts, a bisadduct was obtained. Reductive MC activation with Na2S2O4 (sodium dithionite) leads to exclusive bifunctional alkylation. The structure of the bisadduct was determined by spectroscopic methods that included proton magnetic resonance, differential Fourier transform infrared spectroscopy, and circular dichroism. Formation of the same bisadduct in vivo was demonstrated upon injection of rats with MC. Computer-generated models of the bisadduct that was incorporated into the center of the duplex B-DNA decamer d(CGTACGTACG)2 indicated that the bisadduct fit snugly into the minor groove with minimal distortion of DNA structure. A mechanistic analysis of the factors that govern monofunctional and bifunctional adduct formation is presented. 相似文献
16.
曹盛丰 《上海交通大学学报(农业科学版)》1993,(2)
大鼠分别按自由采食(AC组)、限饲能量(RC组)、自由采食+AFB_1(黄曲霉毒素B_1,AT组)和限饲能量+AFB_1(RT组)处理16周后,检测肝微粒体Cyt P-450.结果表明:各组Cyt P-450总量变化不大:Cyt P-450_bRC组和RT组分别高于AC组和AT组(P<0.01);Cyt P-450_cRc组比AC组增加30.6％(P>0.05),RT组比AT组增加45.0％(P<0.05);微粒体酶调节的体外3~H-AFB_1与DNA结合RC和RT组分别低于AC和AT组.表明能量限制对Cyt P-450_b和Cyt p-450_c有修饰作用。能量及AFB_1-DNA结合与Cyt P-450_b和Cyt P-450_c相关性检验提示,Cyt P-450_b和Cyt P-450_c活性的提高可能是能量限制引起微粒体酶调节的3~H-AFB_1-DNA结合下降的原因之一。 相似文献
17.
Sequence-specific DNA binding by a short peptide dimer 总被引：33，自引：0，他引：33
18.
The DNA-binding properties of the major regulatory protein alpha 4 of herpes simplex viruses 总被引：58，自引：0，他引：58
N Michael D Spector P Mavromara-Nazos T M Kristie B Roizman 《Science (New York, N.Y.)》1988,239(4847):1531-1534
The transition from the expression of alpha, the first set of five herpes simplex virus genes expressed after infection, to beta and gamma genes, expressed later in infection, requires the participation of infected cell protein 4 (alpha 4), the major viral regulatory protein. The alpha 4 protein is present in complexes formed by proteins extracted from infected cells and viral DNA fragments derived from promoter domains. This report shows that the alpha 4 protein forms specific complexes with DNA fragments derived from 5' transcribed noncoding domains of late (gamma 2) genes whose expression requires viral DNA synthesis as well as functional alpha 4 protein. Some of the DNA fragments to which alpha 4 binds do not contain homologs of the previously reported DNA binding site consensus sequence, suggesting that alpha 4 may recognize and interact with more than one type of DNA binding site. The alpha 4 proteins can bind to DNA directly. A posttranslationally modified form of the alpha 4 protein designated alpha 4c differs from the alpha 4a and alpha 4b forms with respect to its affinity for DNA fragments differing in the nucleotide sequences of the binding sites. 相似文献
19.
International HIV Controllers Study Pereyra F Jia X McLaren PJ Telenti A de Bakker PI Walker BD Ripke S Brumme CJ Pulit SL Carrington M Kadie CM Carlson JM Heckerman D Graham RR Plenge RM Deeks SG Gianniny L Crawford G Sullivan J Gonzalez E Davies L Camargo A Moore JM Beattie N Gupta S Crenshaw A Burtt NP Guiducci C Gupta N Gao X Qi Y Yuki Y Piechocka-Trocha A Cutrell E Rosenberg R Moss KL Lemay P O'Leary J Schaefer T Verma P Toth I Block B Baker B Rothchild A Lian J Proudfoot J Alvino DM 《Science (New York, N.Y.)》2010,330(6010):1551-1557
Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection. 相似文献
20.
The signal recognition particle (SRP) is a universally conserved ribonucleoprotein complex that mediates the cotranslational targeting of secretory and membrane proteins to cellular membranes. A crucial early step in SRP assembly in archaea and eukarya is the binding of protein SRP19 to specific sites on SRP RNA. Here we report the 1.8 angstrom resolution crystal structure of human SRP19 in complex with its primary binding site on helix 6 of SRP RNA, which consists of a stem-loop structure closed by an unusual GGAG tetraloop. Protein-RNA interactions are mediated by the specific recognition of a widened major groove and the tetraloop without any direct protein-base contacts and include a complex network of highly ordered water molecules. A model of the assembly of the SRP core comprising SRP19, SRP54, and SRP RNA based on crystallographic and biochemical data is proposed. 相似文献