Abstract:
:Loop length and its composition are important for the structural and functional versatility of quadruplexes. To date studies on the loops have mainly concerned model sequences compared with naturally occurring quadruplex sequences which have diverse loop lengths and compositions. Herein, we have characterized 36 quadruplex-forming sequences from the promoter regions of various proto-oncogenes using CD, UV and native gel electrophoresis. We examined folding topologies and determined the thermodynamic profile for quadruplexes varying in total loop length (5-18 bases) and composition. We found that naturally occurring quadruplexes have variable thermodynamic stabilities (DeltaG(37)) ranging from -1.7 to -15.6 kcal/mol. Overall, our results suggest that both loop length and its composition affect quadruplex structure and thermodynamics, thus making it difficult to draw generalized correlations between loop length and thermodynamic stability. Additionally, we compared the thermodynamic stability of quadruplexes and their respective duplexes to understand quadruplex-duplex competition. Our findings invoke a discussion on whether biological function is associated with quadruplexes with lower thermodynamic stability which undergo facile formation and disruption, or by quadruplexes with high thermodynamic stability.
journal_name
Nucleic Acids Resjournal_title
Nucleic acids researchauthors
Kumar N,Maiti Sdoi
10.1093/nar/gkn543subject
Has Abstractpub_date
2008-10-01 00:00:00pages
5610-22issue
17eissn
0305-1048issn
1362-4962pii
gkn543journal_volume
36pub_type
杂志文章abstract::A soluble enzyme system that specifically initiates lambda dv plasmid DNA replication at a bacteriophage lambda replication origin [Wold et al. (1982) Proc. Natl. Acad. Sci. USA 79, 6176-6180] is also capable of replicating the single-stranded circular chromosomes of phages M13 and phi X174 to a duplex form. This chai...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/12.7.3069
更新日期:1984-04-11 00:00:00
abstract::We have adapted a method for making libraries of mutations in any specific gene for use in the fission yeast Schizosaccharomyces pombe . This elegant and simple method consists of PCR amplification of the gene of interest, followed by co-transformation of fission yeast with the PCR fragment and a linearized plasmid ve...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/26.20.4783
更新日期:1998-10-15 00:00:00
abstract::We describe a new, broadly applicable methodology for screening in parallel interactions of RNA-binding proteins (RBPs) with large numbers of microRNA (miRNA) precursors and for determining their affinities in native form in the presence of cellular factors. The assays aim at identifying pre-miRNAs that are potentiall...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gks1197
更新日期:2013-02-01 00:00:00
abstract::We have developed efficient methods for creating artificial transposons and inserting these transposons into plasmid targets in vitro, primarily for the purpose of DNA mapping and sequencing. A novel plasmid has been engineered to convert virtually any DNA sequence, or combination of sequences, into an artificial tran...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/22.18.3765
更新日期:1994-09-11 00:00:00
abstract::The helical twist of poly d(A-s4T) was determined from the periodicity of the cleavage patterns of the double stranded polydeoxynucleotide adsorbed on calcium phosphate and found to be 14 bp per turn. Both cleavage patterns and 31P NMR spectra indicate a mononucleotide structure rather than an alternating B DNA like p...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/14.5.2241
更新日期:1986-03-11 00:00:00
abstract::Numerous examples exist of how disrupting the actions of physiological regulators of blood cell development yields hematologic malignancies. The master regulator of hematopoietic stem/progenitor cells GATA-2 was cloned almost 20 years ago, and elegant genetic analyses demonstrated its essential function to promote hem...
journal_title:Nucleic acids research
pub_type: 杂志文章,评审
doi:10.1093/nar/gks281
更新日期:2012-07-01 00:00:00
abstract::Variable (diversity) joining [V(D)J] recombination of immune gene loci proceeds in an ordered manner with D to J portions recombining first and then an upstream V joins that recombinant. We present evidence that the non-core domain of recombination activating gene (RAG) protein 2 is involved in the regulation of recom...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gkn553
更新日期:2008-10-01 00:00:00
abstract::The cellular response to DNA double-strand breaks (DSBs) is initiated by the Mre11-Rad50-Xrs2 (MRX) complex that has structural and catalytic functions. MRX association at DSBs is counteracted by Rif2, which is known to interact with Rap1 that binds telomeric DNA through two tandem Myb-like domains. Whether and how Ra...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gkz1203
更新日期:2020-03-18 00:00:00
abstract::A reporter assay was developed to detect and quantify nonsense codon suppression by chemically aminoacylated tRNAs in mammalian cells. It is based on the cellular expression of the enhanced green fluorescent protein (EGFP) as a reporter for the site-specific amino acid incorporation in its sequence using an orthogonal...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gnf128
更新日期:2002-12-01 00:00:00
abstract::DNA fragments containing mispaired and modified bases, bulges, lesions and specific sequences have altered conformation. Methods for separating complex samples of DNA fragments based on conformation but independent of length have many applications, including (i) separation of mismatched or unmatched DNA fragments from...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gnh018
更新日期:2004-02-03 00:00:00
abstract::ID elements comprise a rodent SINE (short interspersed DNA repetitive element) family that has amplified by retroposition of a few master genes. In order to understand the important factors of SINE amplification, we investigated the transcription of rat ID elements. Three different size classes of ID transcripts, BC1,...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/23.12.2245
更新日期:1995-06-25 00:00:00
abstract::When the function of origins of replication in yeast was compromised by placing ARS sequences downstream of strong promoters, ARS activity might have been affected either by transcription or by an altered chromatin configuration induced by the construct. To distinguish between these possibilities, derivatives of the y...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/22.19.3904
更新日期:1994-09-25 00:00:00
abstract::Prokaryotes use primed CRISPR adaptation to update their memory bank of spacers against invading genetic elements that have escaped CRISPR interference through mutations in their protospacer target site. We previously observed a trend that nucleotide-dependent mismatches between crRNA and the protospacer strongly infl...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gky687
更新日期:2018-11-02 00:00:00
abstract::Gene expression is a multi-step process involving many layers of regulation. The main regulators of the pathway are DNA and RNA binding proteins. While over the years, a large number of DNA and RNA binding proteins have been identified and extensively studied, it is still expected that many other proteins, some with y...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gkw454
更新日期:2016-07-08 00:00:00
abstract::RecBCD enzyme acts in the major pathway of homologous recombination of linear DNA in Escherichia coli. The enzyme unwinds DNA and is an ATP-dependent double-strand and single-strand exonuclease and a single-strand endonuclease; it acts at Chi recombination hotspots (5'-GCTGGTGG-3') to produce a recombinogenic single-s...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/26.9.2125
更新日期:1998-05-01 00:00:00
abstract::Three copies of a highly repetitive DNA sequence B1 which is complementary to the most abundant class of mouse fold-back RNA have been cloned in pBR322 plasmid and sequenced by the method of Maxam and Gilbert. All the three have a length of about 130 base pairs and are very similar in their base sequence. The deviatio...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/8.6.1201
更新日期:1980-03-25 00:00:00
abstract::Interactions between subunits in the Saccharomyces cerevisiae ribosome are mediated by universal and eukaryote-specific intersubunit bridges. Universal bridges are positioned close to the ribosomal functional centers, while eukaryote-specific bridges are mainly located on the periphery of the ribosome. Two bridges, eB...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gky1083
更新日期:2019-01-10 00:00:00
abstract::Translin is a single-stranded RNA- and DNA-binding protein, which has been highly conserved in eukaryotes, from man to Schizosaccharomyces pombe. TRAX is a Translin paralog associated with Translin, which has coevolved with it. We generated structural models of the S. pombe Translin (spTranslin), based on the solved 3...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gkp1230
更新日期:2010-05-01 00:00:00
abstract::DNA polymerases alpha and delta are essential enzymes believed to play critical roles in initiation and replication of chromosome DNA. In this study, we show that the genes for Schizosaccharomyces pombe (S.pombe) DNA polymerase alpha and delta (pol alpha+ and pol delta+) are essential for cell viability. Disruption of...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/21.16.3821
更新日期:1993-08-11 00:00:00
abstract::The structure of eukaryotic chromatin has been investigated by isolating and analyzing the "accessible" DNA fraction of rat liver chromatin. This DNA fraction has been isolated by titrating the chromatin with the protese-resistant D isomer of polylysine to bind the "accessible" DNA sites. After removal of chromosomal ...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/2.5.667
更新日期:1975-05-01 00:00:00
abstract::The (cytosine-5) DNA methyltransferase M.HhaI causes its target cytosine base to be flipped completely out of the DNA helix upon binding. We have investigated the effects of replacing the target cytosine by other, mismatched bases, including adenine, guanine, thymine and uracil. We find that M.HhaI binds more tightly ...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/23.8.1388
更新日期:1995-04-25 00:00:00
abstract::Kaposi's sarcoma-associated herpesvirus encodes four viral homologues to cellular interferon regulatory factors (IRFs), where the most studied is vIRF-1. Even though vIRF-1 shows sequence homology to the N-terminal DNA-binding domain (DBD) of human IRFs, a specific role for this domain in vIRF-1's function has remaine...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gkt082
更新日期:2013-04-01 00:00:00
abstract::Previous work in predicting protein localization to the chloroplast organelle in plants led to the development of an artificial neural network-based approach capable of remarkable accuracy in its prediction (ChloroP). A common criticism against such neural network models is that it is difficult to interpret the criter...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/29.16.e82
更新日期:2001-08-15 00:00:00
abstract::The dicistrovirus intergenic internal ribosome entry site (IGR IRES) directly recruits the ribosome and initiates translation using a non-AUG codon. A subset of IGR IRESs initiates translation in either of two overlapping open reading frames (ORFs), resulting in expression of the 0 frame viral structural polyprotein a...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gku622
更新日期:2014-08-01 00:00:00
abstract::The binding of anti poly(I). poly (C) Fab fragments to double or triple stranded polynucletides has been studied by fluorescence. Association constants were deduced from competition experiments. The comparison of the association constants leads to the conclusion that several atoms of the base residues do not interact ...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/3.12.3337
更新日期:1976-12-01 00:00:00
abstract::A novel method for sequence specific double strand DNA cleavage using PNA (peptide nucleic acid) targeting is described. Nuclease S1 digestion of double stranded DNA gives rise to double strand cleavage at an occupied PNA strand displacement binding site, and under optimized conditions complete cleavage can be obtaine...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/21.9.2103
更新日期:1993-05-11 00:00:00
abstract::The dynamic topological structure of telomeric DNA is closely related to its biological function; however, no such structural information on full-length telomeric DNA has been reported due to difficulties synthesizing long double-stranded telomeric DNA. Herein, we developed an EM-PCR and TA cloning-based approach to s...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/gkaa479
更新日期:2020-07-09 00:00:00
abstract::The reported binding preference of human hnRNP protein A1 for the 3'-splice site of some introns (Swanson and Dreyfuss (1988) EMBO J. 7, 3519-3529; Mayrand and Pederson (1990) Nucleic Acids Res. 18, 3307-3318) was tested by assaying in vitro the binding of purified recombinant A1 protein (expressed in bacteria) to syn...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/18.22.6595
更新日期:1990-11-25 00:00:00
abstract::We describe the unique features of an aberrantly rearranged mu immunoglobulin heavy chain gene isolated from MPC-11 cells (a gamma 2b producing Balb/c plasmacytoma). A novel rearrangement has occurred 1.5 Kb 5' of the MPC-11 mu gene (denoted 18b mu) resulting in the deletion of the majority of the repetitive switch re...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/10.23.7751
更新日期:1982-12-11 00:00:00
abstract::RNA editing in protozoan parasites is a mitochondrial RNA processing reaction in which exclusively uridylate residues are inserted into, and less frequently deleted from, pre-mRNAs. Molecules central to the process are so-called guide RNAs (gRNAs) which function as templates in the reaction. For a detailed molecular u...
journal_title:Nucleic acids research
pub_type: 杂志文章
doi:10.1093/nar/25.12.2311
更新日期:1997-06-15 00:00:00