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747
RDP3: a flexible and fast computer program for analyzing recombination
- BIOINFORMATICS
, 2010
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STAMP: a web tool for exploring DNA-binding motif similarities.” Nucleic Acids Res, 35(Web Server issue
, 2007
"... doi:10.1093/nar/gkm272 ..."
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M-Coffee: combining multiple sequence alignment methods with T-Coffee
- Nucleic Acids Res
, 2006
"... We introduce M-Coffee, a meta-method for assembling multiple sequence alignments (MSA) by combining the output of several individual methods into one single MSA. M-Coffee is an extension of T-Coffee and uses consistency to estimate a consensus alignment. We show that the procedure is robust to varia ..."
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Cited by 60 (13 self)
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We introduce M-Coffee, a meta-method for assembling multiple sequence alignments (MSA) by combining the output of several individual methods into one single MSA. M-Coffee is an extension of T-Coffee and uses consistency to estimate a consensus alignment. We show that the procedure is robust to variations in the choice of constituent methods and reasonably tolerant to duplicate MSAs. We also show that performances can be improved by carefully selecting the constituent methods. M-Coffee outperforms all the individual methods on three major reference datasets: HOMSTRAD, Prefab and Balibase. We also show that on a case-by-case basis, M-Coffee is twice as likely to deliver the best alignment than any individual method. Given a collection of pre-computed MSAs, M-Coffee has similar CPU requirements to the original T-Coffee. M-Coffee is a freeware open-source package available from
Review SELEX—A (r)evolutionary method to generate high-affinity nucleic acid ligands
, 2007
"... www.elsevier.com/locate/geneanabioeng SELEX stands for systematic evolution of ligands by exponential enrichment. This method, described primarily in 1990 [Ellington, A.D., ..."
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Cited by 46 (2 self)
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www.elsevier.com/locate/geneanabioeng SELEX stands for systematic evolution of ligands by exponential enrichment. This method, described primarily in 1990 [Ellington, A.D.,
Detecting coevolution in and among protein domains
- PLoS Comp. Biol
, 2007
"... Correlated changes of nucleic or amino acids have provided strong information about the structures and interactions of molecules. Despite the rich literature in coevolutionary sequence analysis, previous methods often have to trade off between generality, simplicity, phylogenetic information, and sp ..."
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Cited by 36 (1 self)
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Correlated changes of nucleic or amino acids have provided strong information about the structures and interactions of molecules. Despite the rich literature in coevolutionary sequence analysis, previous methods often have to trade off between generality, simplicity, phylogenetic information, and specific knowledge about interactions. Furthermore, despite the evidence of coevolution in selected protein families, a comprehensive screening of coevolution among all protein domains is still lacking. We propose an augmented continuous-time Markov process model for sequence coevolution. The model can handle different types of interactions, incorporate phylogenetic information and sequence substitution, has only one extra free parameter, and requires no knowledge about interaction rules. We employ this model to large-scale screenings on the entire protein domain database (Pfam). Strikingly, with 0.1 trillion tests executed, the majority of the inferred coevolving protein domains are functionally related, and the coevolving amino acid residues are spatially coupled. Moreover, many of the coevolving positions are located at functionally important sites of proteins/protein complexes, such as the subunit linkers of superoxide dismutase, the tRNA binding sites of ribosomes, the DNA binding region of RNA polymerase, and the active and ligand binding sites of various enzymes. The results suggest sequence coevolution manifests structural and functional constraints of proteins. The intricate relations between sequence coevolution and various selective constraints are worth pursuing at a deeper level.
PolyA_DB 2: mRNA polyadenylation sites in vertebrate genes
- Nucleic Acids Res
, 2007
"... Polyadenylation of nascent transcripts is one of the key mRNA processing events in eukaryotic cells. A large number of human and mouse genes have alternative polyadenylation sites, or poly(A) sites, leading to mRNA variants with different protein products and/or 30-untranslated regions (30-UTRs). Po ..."
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Cited by 34 (6 self)
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Polyadenylation of nascent transcripts is one of the key mRNA processing events in eukaryotic cells. A large number of human and mouse genes have alternative polyadenylation sites, or poly(A) sites, leading to mRNA variants with different protein products and/or 30-untranslated regions (30-UTRs). PolyA_DB 2 contains poly(A) sites identified for genes in several vertebrate species, including human, mouse, rat, chicken and zebrafish, using alignments between cDNA/ESTs and genome sequences. Several new features have been added to the database since its last release, including syntenic genome regions for human poly(A) sites in seven other vertebrates and cis-element information adjacent to poly(A) sites. Trace sequences are used to provide additional evidence for poly(A/T) tails in cDNA/ESTs. The updated database is intended to broaden poly(A) site coverage in vertebrate genomes, and provide means to assess the authenticity of poly(A) sites identified by bioinformatics. The
Pervasive Adaptive Evolution in Primate Seminal Proteins
"... Seminal fluid proteins show striking effects on reproduction, involving manipulation of female behavior and physiology, mechanisms of sperm competition, and pathogen defense. Strong adaptive pressures are expected for such manifestations of sexual selection and host defense, but the extent of positi ..."
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Cited by 29 (0 self)
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Seminal fluid proteins show striking effects on reproduction, involving manipulation of female behavior and physiology, mechanisms of sperm competition, and pathogen defense. Strong adaptive pressures are expected for such manifestations of sexual selection and host defense, but the extent of positive selection in seminal fluid proteins from divergent taxa is unknown. We identified adaptive evolution in primate seminal proteins using genomic resources in a tissue-specific study. We found extensive signatures of positive selection when comparing 161 human seminal fluid proteins and 2,858 prostate-expressed genes to those in chimpanzee. Seven of eight outstanding genes yielded statistically significant evidence of positive selection when analyzed in divergent primates. Functional clues were gained through divergent analysis, including several cases of species-specific loss of function in copulatory plug genes, and statistically significant spatial clustering of positively selected sites near the active site of kallikrein 2. This study reveals previously unidentified positive selection in seven primate seminal proteins, and when considered with findings in Drosophila, indicates that extensive positive selection is found in seminal fluid across divergent taxonomic groups. Citation: Clark NL, Swanson WJ (2005) Pervasive adaptive evolution in primate seminal proteins. PLoS Genet 1(3): e35.
Towards a genome-based taxonomy for prokaryotes
- J
, 2005
"... This article cites 30 articles, 15 of which can be accessed free ..."
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Cited by 28 (2 self)
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This article cites 30 articles, 15 of which can be accessed free
Identification and analysis of ribonuclease P and MRP RNA in a broad range of eukaryotes. Nucleic Acids Res
, 2005
"... RNases P and MRP are ribonucleoprotein complexes involved in tRNA and rRNA processing, respectively. The RNA subunits of these two enzymes are structurally related to each other and play an essential role in the enzymatic reaction. Both of the RNAs have a highly conserved helical region, P4, which i ..."
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Cited by 28 (1 self)
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RNases P and MRP are ribonucleoprotein complexes involved in tRNA and rRNA processing, respectively. The RNA subunits of these two enzymes are structurally related to each other and play an essential role in the enzymatic reaction. Both of the RNAs have a highly conserved helical region, P4, which is important in the catalytic reaction. We have used a bioinformatics approach based on conserved elements to computationally analyze available genomic sequences of eukaryotic organisms and have identified a large number of novel nuclear RNase P and MRP RNA genes. For MRP RNA for instance, this investigation increases the number of known sequences by a factor of three. We present secondary structure models of many of the predicted RNAs. Although all sequences are able to fold into the consensus secondary structure of P and MRP RNAs, a striking variation in size is observed, ranging from a Nosema locustae MRP RNA of 160 nt to much larger RNAs, e.g. a Plasmodium knowlesi P RNA of 696 nt. The P and MRP RNA genes appear in tandem in some protists, further emphasizing the close evolutionary relationship of these RNAs.
Conservation and evolution of cis-regulatory systems in ascomycete fungi
- PloS Biol
, 2004
"... Relatively little is known about the mechanisms through which gene expression regulation evolves. To investigate this, we systematically explored the conservation of regulatory networks in fungi by examining the cis-regulatory elements that govern the expression of coregulated genes. We first identi ..."
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Cited by 26 (1 self)
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Relatively little is known about the mechanisms through which gene expression regulation evolves. To investigate this, we systematically explored the conservation of regulatory networks in fungi by examining the cis-regulatory elements that govern the expression of coregulated genes. We first identified groups of coregulated Saccharomyces cerevisiae genes enriched for genes with known upstream or downstream cis-regulatory sequences. Reasoning that many of these gene groups are coregulated in related species as well, we performed similar analyses on orthologs of coregulated S. cerevisiae genes in 13 other ascomycete species. We find that many species-specific gene groups are enriched for the same flanking regulatory sequences as those found in the orthologous gene groups from S. cerevisiae, indicating that those regulatory systems have been conserved in multiple ascomycete species. In addition to these clear cases of regulatory conservation, we find examples of cis-element evolution that suggest multiple modes of regulatory diversification, including alterations in transcription factor-binding specificity, incorporation of new gene targets into an existing regulatory system, and cooption of regulatory systems to control a different set of genes. We investigated one example in greater detail by measuring the in vitro activity of the S. cerevisiae transcription factor Rpn4p and its orthologs from Candida albicans and Neurospora crassa. Our results suggest that the DNA binding specificity of these proteins has coevolved with the sequences found upstream of the Rpn4p target genes and suggest