HCOP: a searchable database of human orthology predictions.

The HUGO Gene Nomenclature Committee (HGNC) Comparison of Orthology Predictions (HCOP) search tool combines the human, mouse, rat and chicken orthology assertions made by PhIGs, HomoloGene, Ensembl, Inparanoid, Mouse Genome Informatics (MGI) and HGNC, enabling users to identify predicted ortholog pairs for a specified gene or genes. The HCOP resource provides a useful method to integrate, compare and access a variety of disparate sources of human orthology data. The HCOP search tool, data and documentation are available at http://www.gene.ucl.ac.uk/hcop.

The HUGO Gene Nomenclature Database, 2006 updates.

The HUGO Gene Nomenclature Committee (HGNC) aims to give every human gene a unique and ideally meaningful name and symbol. The HGNC database, previously known as Genew, contains over 22,000 public records with approved human gene nomenclature and associated information. The database has undergone major improvements throughout the last year, is publicly available for online searching at http://www.gene.ucl.ac.uk/cgi-bin/nomenclature/searchgenes.pl and has a new custom downloads interface at http://www.gene.ucl.ac.uk/cgi-bin/nomenclature/gdlw.pl.

HCOP: the HGNC comparison of orthology predictions search tool.

The HGNC Comparison of Orthology Predictions search tool, HCOP (http://www.gene.ucl.ac.uk/cgi-bin/nomenclature/hcop.pl ), enables users to compare predicted human and mouse orthologs for a specified gene, or set of genes, from either species according to the ortholog assertions from the Ensembl, HGNC, Homologene, Inparanoid, MGI and PhIGs databases. Users can assess the reliability of the prediction from the number of these different sources that identify a particular orthologous pair. HCOP provides a useful one-stop resource to summarise, compare and access various sources of human and mouse orthology data.

Computational analysis of alpha-helical membrane protein structure: implications for the prediction of 3D structural models.

Relatively little has been known about the structure of alpha-helical membrane proteins, since until recently few structures had been crystallized. These limited data have restricted structural analyses to the prediction of secondary structure, rather than tertiary folds. In order to address this, this paper describes an analysis of the 23 available membrane protein structures. A number of findings are made that are of particular relevance to transmembrane helix packing: (1) on average lipid-tail-accessible transmembrane residues are significantly more hydrophobic, less conserved and contain different residue types to buried residues; (2) charged residues are not always buried and, when accessible to membrane lipid tails, few are paired with another charge and instead they often interact with phospholipid head-groups or with other residue types; (3) a significant proportion of lipid-tail-accessible charged and polar residues form hydrogen bonds only with residues one turn away in the same helix (intra-helix); (4) pore-lining residues are usually hydrophobic and it is difficult to distinguish them from buried residues in terms of either residue type or conservation; and (5) information was gained about the proportion of helices that tend to contribute to lining a pore and the resulting pore diameter. These findings are discussed with relevance to the prediction of membrane protein 3D structure.

The role of the 5-HT1D receptor as a presynaptic autoreceptor in the guinea pig.

The present study investigated the role of the 5-hydroxytryptamine (5-HT, serotonin)1D receptor as a presynaptic autoreceptor in the guinea pig. In keeping with the literature, the 5-HT1B selective antagonist, 1'-methyl-5-[[2'-methyl-4'-(5-methyl-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]carbonyl]-2,3,6,7-tetrahydrospiro [furo[2,3-f]indole-3,4'-piperidine]oxalate (SB224289) potentiated [3H]5-HT outflow from pre-labelled slices of guinea pig cerebral cortex confirming its role as a presynaptic autoreceptor in this species. In addition, the 5-HT1D receptor-preferring antagonists, 1-[2-[4-(6-fluoro-1H-indol-3-yl)-3,6-dihydro-2H-pyridin-1-yl]-ethyl]-3-pyridin-4-yl-methyl-tetrahydro-pyrimidin-2-one (LY367642), (R)-1-[2-(4-(6-fluoro-1H-indol-3-yl-)-3,6-dihydro-1(2H)-pyridinyl)ethyl]-3,4-dihydro-1H-2-benzopyran-6-carboxamide (LY456219), (S)-1-[2-(4-(6-fluoro-1H-indol-3-yl-)-3,6-dihydro-1(2H)-pyridinyl)ethyl]-3,4-dihydro-1H-2-benzopyran-6-carboxamide (LY456220) and 1-[2-[4-(4-fluoro-benzoyl)-piperidin-1-yl]-ethyl]-3,3-dimethyl-1,2-dihydro-indol-2-one (LY310762), potentiated [3H]5-HT outflow from this preparation with potencies (EC50 values=31-140 nM) in the same range as their affinities for the guinea pig 5-HT1D receptor (Ki values=100-333 nM). The selective 5-HT1D receptor agonist, R-2-(4-fluoro-phenyl)-2-[1-[3-(5-[1,2,4]triazol-4-yl-1H-indol-3-yl)-propyl]-piperidin-4-ylamino]-ethanol dioxylate (L-772,405), inhibited [3H]5-HT outflow. In microdialysis studies, administration of either SB224289 or LY310762 at 10 mg/kg by the intraperitoneal (i.p.) route, potentiated the increase in extracellular 5-HT concentration produced by a maximally effective dose of the selective serotonin re-uptake inhibitor, fluoxetine (at 20 mg/kg i.p.). In addition, the 5-HT1D receptor-preferring antagonist and 5-HT transporter inhibitor, LY367642 (at 10 mg/kg i.p.), elevated extracellular 5-HT concentrations to a greater extent than a maximally effective dose of fluoxetine. It is concluded that the 5-HT1D receptor, like the 5-HT1B receptor, may be a presynaptic autoreceptor in the guinea pig.