Browse
Submit Data
Databases
API
Help

Dataset Information

29 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Crystallization and preliminary crystallographic characterization of the PAS domains of EAG and ELK potassium channels.

ABSTRACT: Per-Arnt-Sim (PAS) domains are ubiquitous in nature; they are approximately 130-amino-acid protein domains that adopt a fairly conserved three-dimensional structure despite their low degree of sequence homology. These domains constitute the N-terminus or, less frequently, the C-terminus of a number of proteins, where they exert regulatory functions. PAS-containing proteins generally display two or more copies of this motif. In this work, the crystallization and preliminary analysis of the PAS domains of two eukaryotic potassium channels from the ether-à-go-go (EAG) family are reported.

SUBMITTER: Adaixo R

PROVIDER: S-EPMC2935226 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Crystallization and preliminary crystallographic characterization of the PAS domains of EAG and ELK potassium channels.

Adaixo Ricardo R Morais-Cabral João Henrique JH

Acta crystallographica. Section F, Structural biology and crystallization communications 20100826 Pt 9

Per-Arnt-Sim (PAS) domains are ubiquitous in nature; they are approximately 130-amino-acid protein domains that adopt a fairly conserved three-dimensional structure despite their low degree of sequence homology. These domains constitute the N-terminus or, less frequently, the C-terminus of a number of proteins, where they exert regulatory functions. PAS-containing proteins generally display two or more copies of this motif. In this work, the crystallization and preliminary analysis of the PAS do ...[more]

PMID: 20823525

Similar Datasets

Crystallization and preliminary X-ray crystallographic characterization of a cyclic nucleotide-binding homology domain from the mouse EAG potassium channel.

Project description:The members of the family of voltage-gated KCNH potassium channels play important roles in cardiac and neuronal repolarization, tumour proliferation and hormone secretion. These channels have a C-terminal cytoplasmic domain which is homologous to cyclic nucleotide-binding domains (CNB-homology domains), but it has been demonstrated that channel function is not affected by cyclic nucleotides and that the domain does not bind nucleotides in vitro. Here, the crystallization and preliminary crystallographic analysis of a CNB-homology domain from a member of the KCNH family, the mouse EAG channel, is reported. X-ray diffraction data were collected to 2.2 Å resolution and the crystal belonged to the hexagonal space group P3(1)21.

| S-EPMC3310546 | biostudies-literature

Gating and regulation of KCNH (ERG, EAG, and ELK) channels by intracellular domains.

Project description:The KCNH family comprises the ERG, EAG, and ELK voltage-activated, potassium-selective channels. Distinct from other K channels, KCNH channels contain unique structural domains, including a PAS (Per-Arnt-Sim) domain in the N-terminal region and a CNBHD (cyclic nucleotide-binding homology domain) in the C-terminal region. The intracellular PAS domains and CNBHDs interact directly and regulate some of the characteristic gating properties of each type of KCNH channel. The PAS-CNBHD interaction regulates slow closing (deactivation) of hERG channels, the kinetics of activation and pre-pulse dependent population of closed states (the Cole-Moore shift) in EAG channels and voltage-dependent potentiation in ELK channels. KCNH channels are all regulated by an intrinsic ligand motif in the C-terminal region which binds to the CNBHD. Here, we focus on some recent advances regarding the PAS-CNBHD interaction and the intrinsic ligand.

| S-EPMC7515569 | biostudies-literature

Structural properties of PAS domains from the KCNH potassium channels.

Project description:KCNH channels form an important family of voltage gated potassium channels. These channels include a N-terminal Per-Arnt-Sim (PAS) domain with unknown function. In other proteins PAS domains are implicated in cellular responses to environmental queues through small molecule binding or involvement in signaling cascades. To better understand their role we characterized the structural properties of several channel PAS domains. We determined high resolution structures of PAS domains from the mouse EAG (mEAG), drosophila ELK (dELK) and human ERG (hERG) channels and also of the hERG domain without the first nine amino acids. We analyzed these structures for features connected to ligand binding and signaling in other PAS domains. In particular, we have found cavities in the hERG and mEAG structures that share similarities with the ligand binding sites from other PAS domains. These cavities are lined by polar and apolar chemical groups and display potential flexibility in their volume. We have also found that the hydrophobic patch on the domain β-sheet is a conserved feature and appears to drive the formation of protein-protein contacts. In addition, the structures of the dELK domain and of the truncated hERG domain revealed the presence of N-terminal helices. These helices are equivalent to the helix described in the hERG NMR structures and are known to be important for channel function. Overall, these channel domains retain many of the PAS domain characteristics known to be important for cell signaling.

| S-EPMC3598652 | biostudies-literature

Crystallization and preliminary crystallographic characterization of glutamine synthetase from Medicago truncatula.

Project description:The condensation of ammonium and glutamate into glutamine catalyzed by glutamine synthetase (GS) is a fundamental step in nitrogen metabolism in all kingdoms of life. In plants, this is preceded by the reduction of inorganic nitrogen to an ammonium ion and therefore effectively articulates nitrogen fixation and metabolism. Although the three-dimensional structure of the dodecameric bacterial GS was determined quite some time ago, the quaternary architecture of the plant enzyme has long been assumed to be octameric, mostly on the basis of low-resolution electron-microscopy studies. Recently, the crystallographic structure of a monocotyledonous plant GS was reported that revealed a homodecameric organization. In order to unambiguously establish the quaternary architecture of GS from dicotyledonous plants, GS1a from the model legume Medicago truncatula was overexpressed, purified and crystallized. The collection of synchrotron diffraction data to 2.35 A resolution allowed the determination of the three-dimensional structure of this enzyme by molecular replacement.

| S-EPMC2802889 | biostudies-literature

Chlorpromazine binding to the PAS domains uncovers the effect of ligand modulation on EAG channel activity.

Project description:Ether-a-go-go (EAG) potassium selective channels are major regulators of neuronal excitability and cancer progression. EAG channels contain a Per-Arnt-Sim (PAS) domain in their intracellular N-terminal region. The PAS domain is structurally similar to the PAS domains in non-ion channel proteins, where these domains frequently function as ligand-binding domains. Despite the structural similarity, it is not known whether the PAS domain can regulate EAG channel function via ligand binding. Here, using surface plasmon resonance, tryptophan fluorescence, and analysis of EAG currents recorded in Xenopus laevis oocytes, we show that a small molecule chlorpromazine (CH), widely used as an antipsychotic medication, binds to the isolated PAS domain of EAG channels and inhibits currents from these channels. Mutant EAG channels that lack the PAS domain show significantly lower inhibition by CH, suggesting that CH affects currents from EAG channels directly through the binding to the PAS domain. Our study lends support to the hypothesis that there are previously unaccounted steps in EAG channel gating that could be activated by ligand binding to the PAS domain. This has broad implications for understanding gating mechanisms of EAG and related ERG and ELK K+ channels and places the PAS domain as a new target for drug discovery in EAG and related channels. Up-regulation of EAG channel activity is linked to cancer and neurological disorders. Our study raises the possibility of repurposing the antipsychotic drug chlorpromazine for treatment of neurological disorders and cancer.

| S-EPMC7105296 | biostudies-literature

Crystallization and preliminary crystallographic characterization of the N-terminal Kunitz domain of boophilin.

Project description:Boophilin is a tight-binding thrombin inhibitor composed of two canonical Kunitz-type domains in a tandem arrangement. Thrombin-bound boophilin can inhibit a second trypsin-like serine proteinase, most likely through the reactive loop of its N-terminal Kunitz domain. Here, the crystallization and preliminary crystallographic analysis of the isolated N-terminal domain of boophilin is reported. The crystals belonged to the orthorhombic space group P2(1)2(1)2(1) and diffracted to beyond 1.8 Å resolution using a sealed-tube home source and to 0.87 Å resolution at a synchrotron source.

| S-EPMC3325814 | biostudies-literature

Crystallization and preliminary crystallographic characterization of three peptidic inhibitors in complex with α-thrombin.

Project description:The serine protease thrombin plays a major role in thrombosis and haemostasis. This has driven interest in thrombin inhibitors as potential antithrombotic drugs. Here, the crystallization and preliminary crystallographic analysis of human α-thrombin in complex with three noncovalent peptide inhibitors of the general sequence D-Phe-Pro-D-Arg-P1'-CONH2 are reported. The crystals belonged to the orthorhombic space group P2(1)2(1)2(1) and diffracted to beyond 1.3 Å resolution.

| S-EPMC3079972 | biostudies-literature

Purification, crystallization and preliminary crystallographic characterization of the caspase-recruitment domain of human Nod1.

Project description:The caspase-recruitment domain (CARD) is known to play an important role in apoptosis and inflammation as an essential protein-protein interaction domain. The CARD of the cytosolic pathogen receptor Nod1 was overexpressed in Escherichia coli and purified by affinity chromatography and gel filtration. The purified CARD was crystallized at 277 K using the microseeding method. X-ray diffraction data were collected to 1.9 A resolution. The crystals belong to space group P3(1) or P3(2), with unit-cell parameters a = b = 79.1, c = 80.9 A. Preliminary analysis indicates that there is one dimeric CARD molecule in the asymmetric unit.

| S-EPMC2330101 | biostudies-literature

Crystallization and preliminary crystallographic analysis of manganese lipoxygenase.

Project description:Lipoxygenases constitute a family of nonhaem metal enzymes with catalytic iron or, occasionally, catalytic manganese. Lipoxygenases oxidize polyunsaturated fatty acids with position specificity and stereospecificity to hydroperoxides, which contribute to inflammation and the development of cancer. Little is known about the structural differences between lipoxygenases with Fe or Mn and the metal-selection mechanism. A Pichia pastoris expression system was used for the production of the manganese lipoxygenase of the take-all fungus of wheat, Gaeumannomyces graminis. The active enzyme was treated with α-mannosidase, purified to apparent homogeneity and subjected to crystal screening and X-ray diffraction. The crystals diffracted to 2.6 Å resolution and belonged to space group C2, with unit-cell parameters a = 226.6, b = 50.6, c = 177.92 Å, β = 91.70°.

| S-EPMC3976078 | biostudies-literature

Crystallization and preliminary crystallographic studies of Helicobacter pylori arginase.

Project description:Helicobacter pylori arginase is an important factor in evasion of the host's immune system and contributes to persistent infection by this bacterium. It is unique in many aspects compared with other arginases: for example, it has optimal activity with Co(2+) as a cofactor rather than Mn(2+) and has strongest activity at acidic pH instead of alkaline pH. In this study, H. pylori arginase was purified and crystallized in complex with Mn(2+) and a diffraction data set was collected to 2.2 Å resolution. The crystals belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 94.69, b = 102.24, c = 148.61 Å.

| S-EPMC3107149 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data