Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “bioinformatic database”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources

Prelude and Fugue, predicting local protein structure, early folding regions and structural weaknesses.

UNLABELLED: Prelude&Fugue are bioinformatics tools aiming at predicting the local 3D structure of a protein from its amino acid sequence in terms of seven backbone torsion angle domains, using database-derived potentials. Prelude(&Fugue) computes all lowest free energy conformations of a protein or protein region, ranked by increasing energy, and possibly satisfying some interresidue distance constraints specified by the user. (Prelude&)Fugue detects sequence regions whose predicted structure is significantly preferred relative to other conformations in the absence of tertiary interactions. These programs can be used for predicting secondary structure, tertiary structure of short peptides, flickering early folding sequences and peptides that adopt a preferred conformation in solution. They can also be used for detecting structural weaknesses, i.e. sequence regions that are not optimal with respect to the tertiary fold. AVAILABILITY: http://babylone.ulb.ac.be/Prelude_and_Fugue.

Algorithms↗

Serial analysis of gene expression in turkey sperm storage tubules in the presence and absence of resident sperm.

Turkey sperm lose viability within 8-18 h when stored as liquid semen using current methods and extenders. In contrast, turkey hens maintain viable, fertile sperm in their sperm storage tubules (SST) for 45 or more days following a single insemination. Our long-term objectives are to identify and characterize differentially expressed genes that may underlie this prolonged sperm storage and then use this information to develop improved methods for storing liquid turkey semen. We employed serial analysis of gene expression (SAGE) to compare gene expression patterns in turkey SST recovered from hens after artificial insemination (AI) with extended semen (sperm AI) or extender alone (control AI). We constructed two separate SAGE libraries with SST RNA obtained from sperm and control AI hens. We used these libraries to generate 95,325 ten-base pair SAGE tags. These 95,325 tags represented 27,430 unique genes. The sperm and control AI libraries contained 47,663 and 47,662 tags representing 18,030 and 19,101 putative unique transcripts, respectively. Approximately 1% of these putative unique genes were differentially expressed (P<0.05) between treatments. Tentative annotations were ascribed to the SAGE tag nucleotide sequences by comparing them against publicly available SAGE tag and cDNA sequence databases. Based on its SAGE tag nucleotide sequence, we cloned a partial turkey avidin cDNA and confirmed its up-regulation in the sperm AI SST. The bioinformatics and experimental procedures employed to clone turkey avidin and confirm its differential expression represent a useful paradigm for analyzing SAGE tag data from relatively uncharacterized model systems.

Animals↗

Immunogenic implications of translational readthrough modulate the association of F8 nonsense mutations with inhibitors in Hemophilia A.

BACKGROUND: Among F8 mutation types, main determinants of inhibitor development after replacement therapy in Hemophilia A (HA), nonsense mutations display wide variation in the associated risk. Translational readthrough (Rdthr) at premature termination codons (PTCs) produces traces of full-length factor VIII (FVIII) including missense and wild-type molecules (WT Rdthr), and may influence the immune response involved in inhibitor formation. METHODS: For inhibitor association analysis, we investigated F8 genotypes, inhibitor status and Rdthr features in 335 PTCs (1048 patients), recorded in the European Association for Haemophilia and Allied Disorders (EAHAD) database, and exploited expression of F8 PTCs variants. Mean-differences in affinity of HLA-DR alleles for FVIII WT peptides and their missense counterparts were bioinformatically calculated. RESULTS: WT Rdthr was higher for patients affected by PTCs not associated with inhibitor and was not predicted at all in patients with PTCs detected in at least three inhibitor positive cases (n&#x2009;=&#x2009;136, p&#x2009;=&#x2009;0.0001). WT Rdthr was lower for PTCs in the inhibitor prone FVIII light chain. Among FVIII PTCs fused with luciferase, quantitative output of WT Rdthr negative and positive groups did not differ, potentially highlighting for the positive group the importance of WT Rdthr to decrease inhibitor association. Readthrough output was the lowest among WT Rdthr negative PTCs, highly associated with inhibitors. The WT Rdthr prediction was extended to all PTCs that could arise by single nucleotide variations for the entire F8 coding sequence. Estimated WT Rdthr was higher in PTCs reported in EAHAD than those predicted (n&#x2009;=&#x2009;662), foreseeing a higher risk of developing inhibitors. In silico mean differences in affinity of HLA-DR alleles for WT FVIII peptides and their missense counterparts, potentially arising from Rdthr of PTCs without WT formation (n&#x2009;=&#x2009;297), were higher for missense variants predicted in patients with inhibitors than without (p&#x2009;<&#x2009;0.0001), and increased for PTCs present in more than one patient with inhibitor, potentially supporting immunogenic features. CONCLUSIONS: The new genetic classification of HA PTCs may improve our knowledge about their relationship with inhibitors. It deserves to be explored for estimating inhibitor PTC association in HLA genotyped patients as well as in other human diseases.

Humans↗

Identification of novel cytoskeleton protein involved in spermatogenic cells and sertoli cells of non-obstructive azoospermia based on microarray and bioinformatics analysis.

BACKGROUND: During mammalian spermatogenesis, the cytoskeleton system plays a significant role in morphological changes. Male infertility such as non-obstructive azoospermia (NOA) might be explained by studies of the cytoskeletal system during spermatogenesis. METHODS: The cytoskeleton, scaffold, and actin-binding genes were analyzed by microarray and bioinformatics (771 spermatogenic cellsgenes and 774 Sertoli cell genes). To validate these findings, we cross-referenced our results with data from a single-cell genomics database. RESULTS: In the microarray analyses of three human cases with different NOA spermatogenic cells, the expression of TBL3, MAGEA8, KRTAP3-2, KRT35, VCAN, MYO19, FBLN2, SH3RF1, ACTR3B, STRC, THBS4, and CTNND2 were upregulated, while expression of NTN1, ITGA1, GJB1, CAPZA1, SEPTIN8, and GOLGA6L6 were downregulated. There was an increase in KIRREL3, TTLL9, GJA1, ASB1, and RGPD5 expression in the Sertoli cells of three human cases with NOA, whereas expression of DES, EPB41L2, KCTD13, KLHL8, TRIOBP, ECM2, DVL3, ARMC10, KIF23, SNX4, KLHL12, PACSIN2, ANLN, WDR90, STMN1, CYTSA, and LTBP3 were downregulated. A combined analysis of Gene Ontology (GO) and STRING, were used to predict proteins' molecular interactions and then to recognize master pathways. Functional enrichment analysis showed that the biological process (BP) mitotic cytokinesis, cytoskeleton-dependent cytokinesis, and positive regulation of cell-substrate adhesion were significantly associated with differentially expressed genes (DEGs) in spermatogenic cells. Moleculare function (MF) of DEGs that were up/down regulated, it was found that tubulin bindings, gap junction channels, and tripeptide transmembrane transport were more significant in our analysis. An analysis of GO enrichment findings of Sertoli cells showed BP and MF to be common DEGs. Cell-cell junction assembly, cell-matrix adhesion, and regulation of SNARE complex assembly were significantly correlated with common DEGs for BP. In the study of MF, U3 snoRNA binding, and cadherin binding were significantly associated with common DEGs. CONCLUSION: Our analysis, leveraging single-cell data, substantiated our findings, demonstrating significant alterations in gene expression patterns.

Male↗

Bioinformatics in proteomics.

Proteomics technologies are under continuous improvements and new technologies are introduced. Nowadays high throughput acquisition of proteome data is possible. The young and rapidly emerging field of bioinformatics in proteomics is introducing new algorithms to handle large and heterogeneous data sets and to improve the knowledge discovery process. For example new algorithms for image analysis of two dimensional gels have been developed within the last five years. Within mass spectrometry data analysis algorithms for peptide mass fingerprinting (PMF) and peptide fragmentation fingerprinting (PFF) have been developed. Local proteomics bioinformatics platforms emerge as data management systems and knowledge bases in Proteomics. We review recent developments in bioinformatics for proteomics with emphasis on expression proteomics.

Animals↗

Pan-cancer Bioinformatics Analysis Combined with Colon Cancer Experimental Validation: A Study on TMED3 as a Diagnostic and Prognostic Biomarker.

Transmembrane Emp24 Protein Transport Domain 3 (TMED3), a member of the p24 protein family, has been implicated in tumor proliferation, invasion, and migration. This study aimed to evaluate the expression patterns, prognostic significance, immune associations, and potential biological functions of TMED3 across multiple cancer types using pan-cancer bioinformatics analysis combined with immunohistochemical (IHC) validation in colon cancer. Multiomics datasets from The Cancer Genome Atlas, Genotype-Tissue Expression, UALCAN, Human Protein Atlas, and cBioPortal databases were analyzed to investigate TMED3 expression and genetic alterations in pan-cancer. Immunohistochemistry was performed to evaluate TMED3 protein expression in colon cancer tissues. Kaplan-Meier survival analysis and Cox regression analysis were used to assess the prognostic value of TMED3. Spearman correlation analysis was conducted to evaluate the associations of TMED3 with tumor mutational burden, microsatellite instability (MSI), immune cell infiltration, and immune checkpoints. Gene Set Enrichment Analysis was performed to investigate potential biological pathways associated with TMED3 in colon cancer. TMED3 expression was elevated in most tumor types and was associated with unfavorable overall survival and disease-specific survival in adrenocortical carcinoma, colon adenocarcinoma, and uveal melanoma. The greatest frequency of TMED3 genetic alterations was identified in mesothelioma, with amplification representing the predominant alteration type. In addition, TMED3 expression showed significant correlations with tumor mutational burden and microsatellite instability in kidney renal clear cell carcinoma, stomach adenocarcinoma, and uterine corpus endometrial carcinoma. TMED3 expression was also associated with immune infiltration and immune checkpoint expression in several tumors. IHC analysis demonstrated increased TMED3 expression in colon cancer tissues compared with normal colon tissues and showed an association with T stage. Functional enrichment analysis identified pathways related to ribosome, antigen processing and presentation, oxidative phosphorylation, and pentose phosphate. These findings indicate that TMED3 may represent a promising biomarker for the diagnosis and prognostic evaluation of colon cancer as well as other tumor types.

Humans↗

Structural principles governing domain motions in proteins.

With the use of a recently developed method, twenty-four proteins for which two or more X-ray conformers are known have been analyzed to reveal structural principles that govern domain motions in proteins. In all 24 cases, the domain motion is a rotation about a physical axis created through local interactions both covalent and noncovalent. In many cases, two or more mechanical hinges separated in space create a stable hinge axis for precise control of the domain closure. The terminal regions of alpha-helices and beta-sheets have been found to act as mechanical hinges in a significant number of cases. In some cases, the two terminal regions of neighboring strands of a single beta-sheet can create a hinge axis, as can the two termini of a single alpha-helix. These two structures have been termed the "double-hinged beta-sheet" and "double-hinged alpha-helix," respectively. A flexible loop that attaches one domain to another and through which the effective hinge axis passes is another construct that is used to create a hinge. Noncovalent interactions between segments remote along the polypeptide chain can also form hinges. In addition alpha-helices that preserve their hydrogen bonding structure when bent have been found to behave as mechanical hinges. It is suggested that these alpha-helices act as a store of elastic energy that drives the closing of domains for rapid capture of the substrate. If the repertoire of possible interdomain structures is as limited as this study suggests, the dynamic behavior of proteins could soon be predicted using bioinformatics techniques. Proteins 1999;36:425-435.

Animals↗

Mouse models of human cancer web-based resources.

The Mouse Models of Human Cancers Consortium (MMHCC) is a collaborative program designed to derive and characterize mouse models of human malignancies. To enhance information and resource exchange among the MMHCC investigators and other cancer research scientists, the NCI Center for Bioinformatics (NCICB, http://ncicb.nci.nih.gov/) has developed web-based resources that are freely available to the cancer research community. These resources include a website (http://emice.nci.nih.gov) and databases for cancer models (http://cancermodels.nci.nih.gov) and cancer images (http://cancerimages.nci.nih.gov).

Animals↗

Missense mutations in the BRCT domain of BRCA-1 from high-risk women frequently perturb strongly hydrophobic amino acids conserved among mammals.

Inherited missense mutations in the tumor suppressor gene, BRCA-1, may predispose to breast or ovarian cancer, but the exact effects on the protein are generally unknown. The COOH-terminal region of BRCA-1 encodes two BRCT repeats, which are partially conserved in mammalian species (human, dog, rat, and mouse; 60% amino acid identity). A bioinformatic analysis was conducted to evaluate 246 BRCT missense mutations from high-risk breast and/or ovarian cancer patients (reported in the NIH Breast Cancer Information Core database). It was hypothesized that amino acids conserved in evolution would be disproportionately targeted by the mutations and that conserved amino acids with strongly hydrophobic side chains would be disproportionately perturbed. A statistical model was developed, and chi(2) tests were used to determine whether missense mutations are randomly distributed throughout the BRCT repeats or whether they disproportionately target certain amino acids. The results showed that missense mutations disproportionately target amino acids that are identical in all four mammals (chi(2) = 46.01, P < 0.001). In addition, missense mutations disproportionately perturb conserved amino acids with strongly hydrophobic side chains (chi(2) = 68.57, P < 0.001) and alter the strongly hydrophobic property. The two most frequently observed known cancer-predisposing missense mutations in the BRCT repeats, M1775R and A1708E, conform to this pattern. These results suggest that missense mutations affecting highly conserved amino acids with strongly hydrophobic side chains can disturb important features of the BRCA-1 protein and may play a role in breast and ovarian cancer formation.

Amino Acid Sequence↗

Finding potential ligands for PDZ domains by tailfit, a JAVA program.

OBJECTIVE: To deduce all potential ligands undiscovered experimentally by searching all the proteins containing same C-termini, which can bind a certain PDZ domain. METHODS: We developed a JAVA program for searching short exact sequence matches at C-terminus. According to the known C-termini, which PDZ domains recognized experimentally, Swissprot database has been searched by this program for all potential ligands. RESULTS: Some PDZ domains may have more potential ligand proteins, which are undiscovered yet experimentally. These bioinformatic results also provide clues for studying functions of hypothetical proteins and PDZ domains' protein interactions in many different organisms. CONCLUSION: The results may provide useful clues for discovering potential functions of hypothetical proteins and new functions of known proteins.

Amino Acid Sequence↗

Functional annotation and analysis of Korean patented biological sequences using bioinformatics.

A recent report of the Korean Intellectual Property Office (KIPO) showed that the number of biological sequence-based patents is rapidly increasing in Korea. We present biological features of Korean patented sequences though bioinformatic analysis. The analysis is divided into two steps. The first is an annotation step in which the patented sequences were annotated with the Reference Sequence (RefSeq) database. The second is an association step in which the patented sequences were linked to genes, diseases, pathway, and biological functions. We used Entrez Gene, Online Mendelian Inheritance in Man (OMIM), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Ontology (GO) databases. Through the association analysis, we found that nearly 2.6% of human genes were associated with Korean patenting, compared to 20% of human genes in the U.S. patent. The association between the biological functions and the patented sequences indicated that genes whose products act as hormones on defense responses in the extra-cellular environments were the most highly targeted for patenting. The analysis data are available at http://www.patome.net.

Base Sequence↗

[A novel method of the genome-wide prediction for the target genes and its application].

Based on the protein databases of several model species, this study developed a new method of the Genome-wide prediction for the target genes, using Hidden Markov model by Perl programming. The advantages of this method are high throughput, high quality and easy prediction, especially in the case of multi-domains proteins families. By this method, we predicted the PPR and TPR proteins families in whole genome of several model species. There were 536 PPR proteins and 199 TPR proteins in Oryza sativa ssp. japonica, 519 PPR proteins and 177 TPR proteins in Oryza sativa L. ssp. indica, 735 PPR proteins and 292 TPR proteins in Arabidopsis thaliana, 6 PPR proteins and 32 TPR proteins in Cyanidioschyzon merolae. Synechococcus and Thermophilic archaebacterium did not have PPR proteins. By contrast, 10 TPR proteins were found in Synechococcus and 4 TPR proteins were found in Thermophilic archaebacterium. Moreover, of these results, some further bioinformatics analyses were conducted.

Bacterial Proteins↗

[Cloning of an expressed sequence tag with restriction display polymerase chain reaction].

OBJECTIVE: To isolate gene fragments from SH-SY5Y cells by way of restriction display polymerase chain reaction (RD-PCR). METHODS: Total mRNA was extracted from SH-SY5Y cells followed by synthesis of the single-strand cDNA with Oligo (dT18) as the anchored primer, and the second strand was synthesized by nick translation. The double strands were cleft with restriction enzyme Sau3A I and the fragments ligated with a universal adapter to be amplified with the universal primers and selected primers. The products were then ligated into the pMD18-T vector and sequenced. RESULTS: One of the sequenced clones was retrieved in the National Center for Biotechnology Information (NCBI) databases with Blast program. The results showed that the sequence possessed great similarity to one fragment of the 17th chromosome in the genome. Sequence analysis with GenScan software indicated that the EST might be one section of an unknown gene. CONCLUSION: RD-PCR provides simple and efficient approach for isolating EST from cells, and cDNA clone sequencing combined with bioinformatics analysis may be helpful in identifying new genes.

Base Sequence↗

Mass spectrometry-based proteomics combined with bioinformatic tools for bacterial classification.

Timely classification and identification of bacteria is of vital importance in many areas of public health. We present a mass spectrometry (MS)-based proteomics approach for bacterial classification. In this method, a bacterial proteome database is derived from all potential protein coding open reading frames (ORFs) found in 170 fully sequenced bacterial genomes. Amino acid sequences of tryptic peptides obtained by LC-ESI MS/MS analysis of the digest of bacterial cell extracts are assigned to individual bacterial proteomes in the database. Phylogenetic profiles of these peptides are used to create a matrix of sequence-to-bacterium assignments. These matrixes, viewed as specific assignment bitmaps, are analyzed using statistical tools to reveal the relatedness between a test bacterial sample and the microorganism database. It is shown that, if a sufficient amount of sequence information is obtained from the MS/MS experiments, a bacterial sample can be classified to a strain level by using this proteomics method, leading to its positive identification.

Amino Acid Sequence↗

Building a human kinase gene repository: bioinformatics, molecular cloning, and functional validation.

Kinases catalyze the phosphorylation of proteins, lipids, sugars, nucleosides, and other important cellular metabolites and play key regulatory roles in all aspects of eukaryotic cell physiology. Here, we describe the mining of public databases to collect the sequence information of all identified human kinase genes and the cloning of the corresponding ORFs. We identified 663 genes, 511 encoding protein kinases, and 152 encoding nonprotein kinases. We describe the successful cloning and sequence verification of 270 of these genes. Subcloning of this gene set in mammalian expression vectors and their use in high-throughput cell-based screens allowed the validation of the clones at the level of expression and the identification of previously uncharacterized modulators of the survivin promoter. Moreover, expressions of the kinase genes in bacteria, followed by autophosphorylation assays, identified 21 protein kinases that showed autocatalytic activity. The work described here will facilitate the functional assaying of this important gene family in phenotypic screens and their use in biochemical and structural studies.

Animals↗

Mass spectrometric identification of proteins and characterization of their post-translational modifications in proteome analysis.

High-throughput DNA sequencing has resulted in increasing input in protein sequence databases. Today more than 20 genomes have been sequenced and many more will be completed in the near future, including the largest of them all, the human genome. Presently, sequence databases contain entries for more than 425.000 protein sequences. However, the cellular functions are determined by the set of proteins expressed in the cell--the proteome. Two-dimensional gel electrophoresis, mass spectrometry and bioinformatics have become important tools in correlating the proteome with the genome. The current dominant strategies for identification of proteins from gels based on peptide mass spectrometric fingerprinting and partial sequencing by mass spectrometry are described. After identification of the proteins the next challenge in proteome analysis is characterization of their post-translational modifications. The general problems associated with characterization of these directly from gel separated proteins are described and the current state of art for the determination of phosphorylation, glycosylation and proteolytic processing is illustrated.

Computational Biology↗

[Bioinformatics analysis of autophagy 5 gene structure].

In order to study the relationship between autophagy and apoptosis, APG5 gene structure was revealed by bioinformatics analysis and meantime a new isoform resulted from alternative splicing of the hAPG5 gene was confirmed, which was hereby designated as human autophagy 5 beta (hAPG5 beta; LOCUS AF293841, GenBank). We cloned and sequenced the cDNAs from fetal brain and B cell cDNA libraries using the known hAPG5 cDNA open reading frame sequences as primers. The cDNA obtained from the human fetal brain cDNA library was identical to the known hAPG5 cDNA. However, the cDNA from adult brain cDNA library was 129 bp shorter in length, lacking the sequence corresponding to those from positions 434 to 563 of the hAPG5 cDNA. Through search in public database and sequence comparisons and assembly 4 related sequences, APG5 genomic sequence was obtained. We found that the hAPG5 gene had 8 exons, and those sequences missing in hAPG5 beta cDNA exactly corresponded to exon 3. By bioinformatics software, the structure of introns, exons, splicing sites, promoter and polyA were demonstrated. Moreover, we were able to express both hAGP5 and 5 beta cDNA clones in human hepatocytes and HeLa cells using pEGFP-C1 vector. In conclusion, our data indicate that a systematic bioinformatics method of finding protein diversity from alternative splicing is a good approach in post-genome biology.

Amino Acid Sequence↗

cDNA2Genome: a tool for mapping and annotating cDNAs.

BACKGROUND: In the last years several high-throughput cDNA sequencing projects have been funded worldwide with the aim of identifying and characterizing the structure of complete novel human transcripts. However some of these cDNAs are error prone due to frameshifts and stop codon errors caused by low sequence quality, or to cloning of truncated inserts, among other reasons. Therefore, accurate CDS prediction from these sequences first require the identification of potentially problematic cDNAs in order to speed up the posterior annotation process. RESULTS: cDNA2Genome is an application for the automatic high-throughput mapping and characterization of cDNAs. It utilizes current annotation data and the most up to date databases, especially in the case of ESTs and mRNAs in conjunction with a vast number of approaches to gene prediction in order to perform a comprehensive assessment of the cDNA exon-intron structure. The final result of cDNA2Genome is an XML file containing all relevant information obtained in the process. This XML output can easily be used for further analysis such us program pipelines, or the integration of results into databases. The web interface to cDNA2Genome also presents this data in HTML, where the annotation is additionally shown in a graphical form. cDNA2Genome has been implemented under the W3H task framework which allows the combination of bioinformatics tools in tailor-made analysis task flows as well as the sequential or parallel computation of many sequences for large-scale analysis. CONCLUSIONS: cDNA2Genome represents a new versatile and easily extensible approach to the automated mapping and annotation of human cDNAs. The underlying approach allows sequential or parallel computation of sequences for high-throughput analysis of cDNAs.

Chromosome Mapping↗