41 research outputs found
SAGETTARIUS: a program to reduce the number of tags mapped to multiple transcripts and to plan SAGE sequencing stages
SAGE (Serial Analysis of Gene Expression) experiments generate short nucleotide sequences called âtagsâ which are assumed to map unambiguously to their original transcripts (1 tag to 1 transcript mapping). Nevertheless, many tags are generated that do not map to any transcript or map to multiple transcripts. Current bioinformatics resources, such as SAGEmap and TAGmapper, have focused on reducing the number of unmapped tags. Here, we describe SAGETTARIUS, a new high-throughput program that performs successive precise Nla3 and Sau3A tag to transcript mapping, based on specifically designed Virtual Tag (VT) libraries. First, SAGETTARIUS decreases the number of tags mapped to multiple transcripts. Among the various mapping resources compared, SAGETTARIUS performed the best in this respect by decreasing up to 11% the number of multiply mapped tags. Second, SAGETTARIUS allows the establishment of a guideline for SAGE experiment sequencing efforts through efficient mapping of the CRT (Cytoplasmic Ribosomal protein Transcripts)-specific tags. Using all publicly available human and mouse Nla3 SAGE experiments, we show that sequencing 100 000 tags is sufficient to map almost all CRT-specific tags and that four sequencing stages can be identified when carrying out a human or mouse SAGE project. SAGETTARIUS is web interfaced and freely accessible to academic users
PromAn: an integrated knowledge-based web server dedicated to promoter analysis
PromAn is a modular web-based tool dedicated to promoter analysis that integrates distinct complementary databases, methods and programs. PromAn provides automatic analysis of a genomic region with minimal prior knowledge of the genomic sequence. Prediction programs and experimental databases are combined to locate the transcription start site (TSS) and the promoter region within a large genomic input sequence. Transcription factor binding sites (TFBSs) can be predicted using several public databases and user-defined motifs. Also, a phylogenetic footprinting strategy, combining multiple alignment of large genomic sequences and assignment of various scores reflecting the evolutionary selection pressure, allows for evaluation and ranking of TFBS predictions. PromAn results can be displayed in an interactive graphical user interface, PromAnGUI. It integrates all of this information to highlight active promoter regions, to identify among the huge number of TFBS predictions those which are the most likely to be potentially functional and to facilitate user refined analysis. Such an integrative approach is essential in the face of a growing number of tools dedicated to promoter analysis in order to propose hypotheses to direct further experimental validations. PromAn is publicly available at http://bips.u-strasbg.fr/PromA
PromAn: an integrated knowledge-based web server dedicated to promoter analysis
PromAn is a modular web-based tool dedicated to promoter analysis that integrates distinct complementary databases, methods and programs. PromAn provides automatic analysis of a genomic region with minimal prior knowledge of the genomic sequence. Prediction programs and experimental databases are combined to locate the transcription start site (TSS) and the promoter region within a large genomic input sequence. Transcription factor binding sites (TFBSs) can be predicted using several public databases and user-defined motifs. Also, a phylogenetic footprinting strategy, combining multiple alignment of large genomic sequences and assignment of various scores reflecting the evolutionary selection pressure, allows for evaluation and ranking of TFBS predictions. PromAn results can be displayed in an interactive graphical user interface, PromAnGUI. It integrates all of this information to highlight active promoter regions, to identify among the huge number of TFBS predictions those which are the most likely to be potentially functional and to facilitate user refined analysis. Such an integrative approach is essential in the face of a growing number of tools dedicated to promoter analysis in order to propose hypotheses to direct further experimental validations. PromAn is publicly available at
Tex19 and Sectm1 concordant molecular phylogenies support co-evolution of both eutherian-specific genes
International audienceBackground: Transposable elements (TE) have attracted much attention since they shape the genome and contribute to species evolution. Organisms have evolved mechanisms to control TE activity. Testis expressed 19 (Tex19) represses TE expression in mouse testis and placenta. In the human and mouse genomes, Tex19 and Secreted and transmembrane 1 (Sectm1) are neighbors but are not homologs. Sectm1 is involved in immunity and its molecular phylogeny is unknown. Methods: Using multiple alignments of complete protein sequences (MACS), we inferred Tex19 and Sectm1 molecular phylogenies. Protein conserved regions were identified and folds were predicted. Finally, expression patterns were studied across tissues and species using RNA-seq public data and RT-PCR. Results: We present 2 high quality alignments of 58 Tex19 and 58 Sectm1 protein sequences from 48 organisms. First, both genes are eutherian-specific, i.e., exclusively present in mammals except monotremes (platypus) and marsupials. Second, Tex19 and Sectm1 have both duplicated in Sciurognathi and Bovidae while they have remained as single copy genes in all further placental mammals. Phylogenetic concordance between both genes was significant (p-value < 0.05) and supported co-evolution and functional relationship. At the protein level, Tex19 exhibits 3 conserved regions and 4 invariant cysteines. In particular, a CXXC motif is present in the N-terminal conserved region. Sectm1 exhibits 2 invariant cysteines and an Ig-like domain. Strikingly, Tex19 C-terminal conserved region was lost in Haplorrhini primates while a Sectm1 C-terminal extra domain was acquired. Finally, we have determined that Tex19 and Sectm1 expression levels anti-correlate across the testis of several primates (Ï = â0.72) which supports anti-regulation. Conclusions: Tex19 and Sectm1 co-evolution and anti-regulated expressions support a strong functional relationship between both genes. Since Tex19 operates a control on TE and Sectm1 plays a role in immunity, Tex19 might suppress an immune response directed against cells that show TE activity in eutherian reproductive tissues
High and Low Molecular Weight Hyaluronic Acid Differentially Regulate Human Fibrocyte Differentiation
Following tissue injury, monocytes can enter the tissue and differentiate into fibroblast-like cells called fibrocytes, but little is known about what regulates this differentiation. Extracellular matrix contains high molecular weight hyaluronic acid (HMWHA; âŒ2Ă10(6) Da). During injury, HMWHA breaks down to low molecular weight hyaluronic acid (LMWHA; âŒ0.8-8Ă10(5) Da).In this report, we show that HMWHA potentiates the differentiation of human monocytes into fibrocytes, while LMWHA inhibits fibrocyte differentiation. Digestion of HMWHA with hyaluronidase produces small hyaluronic acid fragments, and these fragments inhibit fibrocyte differentiation. Monocytes internalize HMWHA and LMWHA equally well, suggesting that the opposing effects on fibrocyte differentiation are not due to differential internalization of HMWHA or LMWHA. Adding HMWHA to PBMC does not appear to affect the levels of the hyaluronic acid receptor CD44, whereas adding LMWHA decreases CD44 levels. The addition of anti-CD44 antibodies potentiates fibrocyte differentiation, suggesting that CD44 mediates at least some of the effect of hyaluronic acid on fibrocyte differentiation. The fibrocyte differentiation-inhibiting factor serum amyloid P (SAP) inhibits HMWHA-induced fibrocyte differentiation and potentiates LMWHA-induced inhibition. Conversely, LMWHA inhibits the ability of HMWHA, interleukin-4 (IL-4), or interleukin-13 (IL-13) to promote fibrocyte differentiation.We hypothesize that hyaluronic acid signals at least in part through CD44 to regulate fibrocyte differentiation, with a dominance hierarchy of SAP>LMWHAâ„HMWHA>IL-4 or IL-13
Usage of evolution to contribute information to the study of protein sequence, structure and function relationship
IntĂ©grer lâĂ©volution peut aider Ă comprendre la relation sĂ©quence, structure, fonction des protĂ©ines. Dans un 1er projet, jâai utilisĂ© la phylogĂ©nĂšse molĂ©culaire pour montrer que les gĂšnes Testis expressed 19 » (Tex19) et « Secreted and transmembrane 1 » (Sectm1) coĂ©voluent. Bien que Tex19 et Sectm1 interviennent dans des processus biologiques diffĂ©rents, rĂ©gulation des transposons et immunitĂ© respectivement, la coĂ©volution Ă©tablit entre eux un lien fonctionnel trĂšs fort. Comme Tex19 ne sâexprime que dans le testicule de lâadulte sain et en cellule cancĂ©reuse, ce rĂ©sultat pourrait prĂ©senter un intĂ©rĂȘt en immunothĂ©rapie du cancer. Dans un 2nd projet, je me suis appuyĂ© sur des calculs de modĂ©lisation molĂ©culaire et sur lâanalyse d'Ă©volution de sĂ©quence pour interroger la validitĂ© de la structure de lâhomodimĂšre du domaine de liaison au ligand (LBD) du rĂ©cepteur É aux glucocorticoĂŻdes (GR É) [Bledsoe R.K. et al, 2002]. PremiĂšrement, ce complexe serait vraisemblablement un artefact de contact cristallin. DeuxiĂšmement, jâai identifiĂ© un assemblage alternatif prĂ©sentant les caractĂ©ristiques molĂ©culaires dâune interface de contact biologique.Evolution can help to provide valuable information to understand protein sequence, structure and function relationship. In a first project, I used molecular phylogeny to show the coevolution of âTestis expressed 19â (Tex19) and âSecreted and Transmembrane 1â (Sectm1) genes. Although Tex19 and Sectm1 are involved in different biological pathways, i.e. transposon regulation and immunity respectively, coevolution supports a strong functional relationship between both genes.Since Tex19 is expressed only in adult healthy testis and cancer cells, this result may be useful for cancer immunotherapy. In a second project, I used molecular modelling and sequence evolution analysis to question the validity of the glucocorticoĂŻd receptor É (GR É ) ligand binding domain (LBD) homodimeric assembly [Bledsoe R.K. et al, 2002]. First, this complex is likely a crystallization artefact. Second, I have identified an alternative assembly that presents the molecular characteristics of a biological interface
Usage of evolution to contribute information to the study of protein sequence, structure and function relationship
IntĂ©grer lâĂ©volution peut aider Ă comprendre la relation sĂ©quence, structure, fonction des protĂ©ines. Dans un 1er projet, jâai utilisĂ© la phylogĂ©nĂšse molĂ©culaire pour montrer que les gĂšnes Testis expressed 19 » (Tex19) et « Secreted and transmembrane 1 » (Sectm1) coĂ©voluent. Bien que Tex19 et Sectm1 interviennent dans des processus biologiques diffĂ©rents, rĂ©gulation des transposons et immunitĂ© respectivement, la coĂ©volution Ă©tablit entre eux un lien fonctionnel trĂšs fort. Comme Tex19 ne sâexprime que dans le testicule de lâadulte sain et en cellule cancĂ©reuse, ce rĂ©sultat pourrait prĂ©senter un intĂ©rĂȘt en immunothĂ©rapie du cancer. Dans un 2nd projet, je me suis appuyĂ© sur des calculs de modĂ©lisation molĂ©culaire et sur lâanalyse d'Ă©volution de sĂ©quence pour interroger la validitĂ© de la structure de lâhomodimĂšre du domaine de liaison au ligand (LBD) du rĂ©cepteur É aux glucocorticoĂŻdes (GR É) [Bledsoe R.K. et al, 2002]. PremiĂšrement, ce complexe serait vraisemblablement un artefact de contact cristallin. DeuxiĂšmement, jâai identifiĂ© un assemblage alternatif prĂ©sentant les caractĂ©ristiques molĂ©culaires dâune interface de contact biologique.Evolution can help to provide valuable information to understand protein sequence, structure and function relationship. In a first project, I used molecular phylogeny to show the coevolution of âTestis expressed 19â (Tex19) and âSecreted and Transmembrane 1â (Sectm1) genes. Although Tex19 and Sectm1 are involved in different biological pathways, i.e. transposon regulation and immunity respectively, coevolution supports a strong functional relationship between both genes.Since Tex19 is expressed only in adult healthy testis and cancer cells, this result may be useful for cancer immunotherapy. In a second project, I used molecular modelling and sequence evolution analysis to question the validity of the glucocorticoĂŻd receptor É (GR É ) ligand binding domain (LBD) homodimeric assembly [Bledsoe R.K. et al, 2002]. First, this complex is likely a crystallization artefact. Second, I have identified an alternative assembly that presents the molecular characteristics of a biological interface
Intégration de l'évolution pour contribuer à l'étude de la relation séquence, structure, fonction des protéines
Evolution can help to provide valuable information to understand protein sequence, structure and function relationship. In a first project, I used molecular phylogeny to show the coevolution of âTestis expressed 19â (Tex19) and âSecreted and Transmembrane 1â (Sectm1) genes. Although Tex19 and Sectm1 are involved in different biological pathways, i.e. transposon regulation and immunity respectively, coevolution supports a strong functional relationship between both genes.Since Tex19 is expressed only in adult healthy testis and cancer cells, this result may be useful for cancer immunotherapy. In a second project, I used molecular modelling and sequence evolution analysis to question the validity of the glucocorticoĂŻd receptor É (GR É ) ligand binding domain (LBD) homodimeric assembly [Bledsoe R.K. et al, 2002]. First, this complex is likely a crystallization artefact. Second, I have identified an alternative assembly that presents the molecular characteristics of a biological interface.IntĂ©grer lâĂ©volution peut aider Ă comprendre la relation sĂ©quence, structure, fonction des protĂ©ines. Dans un 1er projet, jâai utilisĂ© la phylogĂ©nĂšse molĂ©culaire pour montrer que les gĂšnes Testis expressed 19 » (Tex19) et « Secreted and transmembrane 1 » (Sectm1) coĂ©voluent. Bien que Tex19 et Sectm1 interviennent dans des processus biologiques diffĂ©rents, rĂ©gulation des transposons et immunitĂ© respectivement, la coĂ©volution Ă©tablit entre eux un lien fonctionnel trĂšs fort. Comme Tex19 ne sâexprime que dans le testicule de lâadulte sain et en cellule cancĂ©reuse, ce rĂ©sultat pourrait prĂ©senter un intĂ©rĂȘt en immunothĂ©rapie du cancer. Dans un 2nd projet, je me suis appuyĂ© sur des calculs de modĂ©lisation molĂ©culaire et sur lâanalyse d'Ă©volution de sĂ©quence pour interroger la validitĂ© de la structure de lâhomodimĂšre du domaine de liaison au ligand (LBD) du rĂ©cepteur É aux glucocorticoĂŻdes (GR É) [Bledsoe R.K. et al, 2002]. PremiĂšrement, ce complexe serait vraisemblablement un artefact de contact cristallin. DeuxiĂšmement, jâai identifiĂ© un assemblage alternatif prĂ©sentant les caractĂ©ristiques molĂ©culaires dâune interface de contact biologique
Sectm1 multiple alignment of complete protein sequences
<p>Multiple alignment of complete Sectm1 protein sequences (58 sequences)</p
Catalog of Tex19 protein sequences
<p>Spreadsheet of Tex19 accession numbers, protein database, short taxonomy, sequence quality annotation</p